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ONTARIO GEOLOGICAL SURVEY
Open File Report 5739
Ontario Geoscience Research Grant Program Grant No. 205
Clay Distribution in Carbonate Reservoirs: Examples from the Silurian of Southwestern Ontario
By
P.L. Churcher and M.B. Dusseault
1991
Parts of this publication may be quoted if credit is given. It is recommended that reference to this publication be made in the following form:
Churcher, PL. and Dusseault, M.B. 1991. Clay distribution in carbonate reservoirs: examples from the silurian of southwestern Ontario; Ontario Geological Survey, Open File Report 5739, 220p.
Queens Printer for Ontario, 1991
Ontario Geological Survey
OPEN FILE REPORT
Open File Reports are made available to the public subject to the following conditions:
This report is unedited. Discrepancies may occur for which the Ontario Geological Survey does not assume liability. Recommendations and statements of opinions expressed are those of the author or authors and are not to be construed as statements of govern ment policy.
This Open File Report is available for viewing at the following locations:
(1) Mines LibraryMinistry of Northern Development and Mines 8th floor, 77 Grenville Street Toronto, Ontario
(2) The office of the Regional or Resident Geologist in whose district the area covered by this report is located.
Copies of this report may be obtained at the user's expense from a commercial printing house. For the address and instructions to order, contact the appropriate Regional or Resident Geologist's office^) or the Mines Library. Microfiche copies (42x reduction) of this report are available for $2.00 each plus provincial sales tax at the Mines Library or the Public Information Centre, Ministry of Natural Resources, W-1640, 99 Wellesley Street West, Toronto.
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The right to reproduce this report is reserved by the Ontario Ministry of Northern Development and Mines. Permission for other reproductions must be obtained in writing from the Director, Ontario Geological Survey.
V.G. Milne, Director Ontario Geological Survey
in
ONTARIO GEOSCIENCE RESEARCH GRANT FOND
Final Research Report
Foreword
This publication is a final report of a research project that was funded under the Ontario Geoscience Research Grant Program. A requirement of the Program is that recipients are to submit final reports within six months after termination of funding.
A final report is designed as a comprehensive summary stating the findings obtained during the tenure of the grant, together with supporting data. It may consist, in part, of reprints or preprints of publications and copies of addresses given at scientific meetings.
It is not the intent of the Ontario Geological Survey to formally publish the final reports for wide distribution, but rather to encourage the recipients of grants to seek publication in appropriate scientific journals whenever possible. The Survey, however, also has an obligation to ensure that the results of the research are made available to the public at an early date. Although final reports are the property of the applicants and the sponsoring agencies, they may also be placed on open file. This report is intended to meet this obligation.
No attempt has been made to edit the report, the content of which is entirely the responsibility of the author(s).
V.G. MilneDirectorOntario Geological Survey
- v -
CONTENTS
Page
ABSTRACT............................................. XV
ACKNOWLEDGMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . XIX
Chapter
l . INTRODUCTION
Statement of Problem ...................... lObjectives- and Assumptions ................ 5Reservoir Selection and Previous Studies . . 6
Reservoir Selection ................. 6Previous Studies . . . . . . . . . . . . . . . . . . . . 10
Partinent Reservoir Information ............ 12Fletcher Patch/Barrier Reef Complex . 12Wilkesport Pinnacle Reef ............ 15
II. METHOD OF STUDY.................................. 17
Delineation of Facies ..................... 17Sampling , Sample Preparation and Analysis... 19
Introduction ........................ 19Sampling and Sample Preparation . . . . . 19X-ray Diffraction Analysis . . . . . . . . . . 23
III. RESULTS AND DISCUTION . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Facies Description and Interpretation . . . . . 25Fletcher Patch/Barrier Reef Complex.. 25Wilkesport Pinnacle Reef ............ 34
Comparison of Reef Types .................. 39Clay Mineral Content ...................... 41
CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
SELECTED BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
CONVERSION TABLE, . , . . . , . , . . . . . . . , . . . . . . . . . . . . . . . . . . . . 221
vii
LIST OF APPENDIXES
A. APPENDIX A-ROUGH CORE LOGGING RESULTS....62
B. APPENDIX B-THIN SECTIONS.................73
C. APPENDIX C-REPRESENTATIVE COREPHOTOGRAPHS. . . . . . . . , . . . . . . . . . . . . . . . . . . . . .116
D. APPENDIX D-DETAILS OF THE METHOD USED FORREMOVAL OF CARBONATE. . . . . . . . . . . . . . . . . . . . . 118
E. APPENDIX E-SELECTION AND TESTING OF THECLAY SEPARATION TECHNIQUE USED...........122
F. APPENDIX F-SCANNING ELECTRON MICROSCOPEAND KEVEX EDS ANALYSIS DATA .............146
G. APPENDIX G-X-RAY DIFFRACTION DATA........206
H. APPENDIX H-CALCULATION OF WEIGHT PERCENTINSOLUBLE RESIDUE........................219
IX
LIST OF FIGURES
Figure page
1.1. Schematic comparison of idealized sandstone (A) and carbonate(B) pore geometries ..................................4
1.2. Silurian stratigraphy of the study area and Michigan . . . . . . . . . . . . . . 8
1.3. Location map .........................................9
1.4. Fletcher reef net pay isopach showing the location of coredholes used in the study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.5. Wilkesport pinnacle reef isopach showing the location of allwells drilled into the structure. I.S. 4 is the core used . . . . . . . . . 16
2.1. Random powder mounts of samples from the Fletcher andWilkesport reservoirs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.1. Facies and gamma log correlation for Consumers 33407 . . . . . . . . . . 26
3.2. Facies and gamma log correlation for Consumers 40001 . . . . . . . . . . 27
3.3. Facies and gamma log correlation for Consumers 40003 . . . . . . . . . . 28
3.4. Facies and gamma log for I.O.E Sombra 4-14-Xin, Wilkesportpinnacle reef. Key to the symbols used found in figure 3.1 . . . . . 35
3.5. X-ray diffraction traces of "vadose silt 1* from Consumers 33323 . . . . 44
xi
LIST OF TABLES
Table page
3.1. Comparison of the two reef types studied . . . . . . . . . . . . . . . . . . . . 40
3.2. Illite whole rock geochemistry - "vadose silt" from Consumers33323 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
3.3. Location of the Illite in the Two Silurian Reservoirs . . . . . . . . . . . . . 47
xiii
ABSTRACT
Clay minerals may play an even greater role in oil recovery from
carbonate reservoirs than they do from sandstone reservoirs because of basic dif
ferences in pore geometry. The narrow, plate-like pore throats of carbonate res
ervoirs with their inherent low permeability are more susceptible to plugging by
fines than the tube-like sandstone pore throats. Thus clay content studies of car
bonate reservoirs are an important part of a reservoir engineering study.
The results of an x-ray diffraction, scanning electron microscope
(SEM), and KEVEX study conducted on two Silurian carbonate reservoirs indicates
the presence of a monominerallic assemblage of detrital illite. These illitic clays,
comprising less than one weight percent, are found in stylolites, vadose silt
seams, marine cements, and in the green shale at the top of the Guelph Forma
tion. Rarely were they observed to be present in the pore space. Clays appear to
be slightly more abundant in the lagoonal environments of the Fletcher Reef than
they are in the reef core environment. In the Wilkesport pinnacle reef it appears
that the clay mineral content is higher in the facies of the supratidal stage of
reef growth and in the underlying Goat Island Formation, than it is in the organic-
reef and biohermal stages.
Four basic facies were delineated during the study of the Fletcher
patch/barrier reef complex. These are, in order of stratigraphic succession, the
coral-stromatoporoid framestone (reef core), stromatoporoid floatstone (eroded
reef top), wackestone (shallow water lagoon), and pelletal wackestone/grainstone
and algal stromatolite facies of the A-l Carbonate (supratidal) facies. Green
xv
shale beds separate the last two facies and mark the contact between the Guelph
Formation and the A-l Carbonate, Salina Formation.
This field produced from two different horizons, consisting of an up
per Guelph-A-1 Carbonate non-reef pay zone, and a lower Guelph reef pay zone.
Porosity and permeability in the lower zone is moderate to high, consisting pri
marily of vug-fracture systems. These types of pore networks are not as suscepti
ble to plugging by the migration of fines, even if sufficient clays were present in
the reservoir at this horizon. In contrast, the porosity and permeability of the
upper zone is significantly less, consisting of fine interparticle pore networks.
This type of porosity may be susceptible to fines plugging, however, the amount
type, and location of the clays delineated in this study would likely pose no signif
icant problems to hydrocarbon production.
Facies in the Wilkesport pinnacle reef can be grouped into the three
stages of reef growth which are the biohermal, organic-reef, and supratidal island
stage. The biohermal stage comprises the debris on which the reef was founded.
The organic-reef stage, consisting of a frame-builder portion and the Brown Nia
garan Reef portion represents the period of maximum reef growth. The suprati
dal island stage represents the final period of reef growth, where the reef was in
termittently subaerially exposed. Sediments in the latter facies consist of
alternating vadose and algal stromatolite beds.
Sedimentological differences were noted between the two Silurian
carbonate reservoirs. The patch/barrier reef, located on the shelf/platform mar
gin is considerably larger than the pinnacle reef, and shows poor faunal zonation.
Pinnacle reefs, on the other hand, are located on the slope, have a limited areal
extent, and exhibit facies distribution with a marked faunal zonation.
xvii
ACKNOWLEDGEMENTS
The writer would like to thank the following individuals and organi
zations for their assistance in this project. Drs. M.B. Dusseault, J.A. Legault,
and D.E. Lawson, M. Coniglio, Waterloo, Dr. L. Evans, and G. Wilson, of the Uni
versity of Guelph. R. Stinson, R. Craig, and S. Colquhoun, of Consumers' Gas, in
Willowdale, and Mr. R. Trevail, Senior Petroleum Geologist, Petroleum Resources
Laboratory, London, Ontario.
This project was funded under Ontario Geoscience Research Fund
Grant 205.
xix
Clay Distribution in Carbonate Reservoirs: Examples from the Silurian ofSouthwestern Ontario
By
P.L Churcher1 and M.B. Dusseault 1
1991
1 Department of Earth Sciences, University of Waterloo
Manuscript approved for publication July 17,1990. Report published with the per mission of V.G. Milne, Director, Ontario Geological Survey.
Chapter l
INTRODUCTION
1.1 STATEMENT OF PROBLEM
Enhanced oil recovery (EOR) techniques are beginning to be em
ployed in Ontario to recover some of the estimated 100 x 10 m of oil remaining
in depleted and partially depleted carbonate reservoirs (P. Palonen, pers. comm.
to M.B. Dusseault, 1983). It is estimated, for most reservoirs, that only 10 to 30
percent of the original oil in place (I.O.I.P) is recovered during the primary pro
duction phase (Dullien,1979). This leaves a valuable untapped resource under
ground. Research is underway to perfect new EOR techniques to meet the spe
cial problems that carbonate reservoirs pose. Proper planning for EOR requires
some fundamental reservoir/geological parameters, among the most important of
which are clay content and behavior (Almon and Da vies, 1981; Hower,1974).
The importance of adequately defining the clay mineral distribution
in hydrocarbon reservoirs has only recently been determined. All reservoirs con
tain detectable amounts of clay minerals and other fines, which when situated in
the pore space, react to foreign fluids introduced into the reservoir during explor
atory drilling, completion/stimulation, or enhanced oil recovery. These minerals
react to the presence of the foreign fluids in a variety of different ways depend
ing on their type, concentration, relative position, and the severity of the change
in the ionic environment (Hower,1974).
For purposes of defining reactivity of clays in hydrocarbon reser
voirs all species may be grouped into four families. These families are illite, kao
linite, smectite and chlorite (Almon and Davies, 1981). Some clays react by
- l -
2
breaking free and migrating (kaolinite, illite, and smectite) usually getting lodged
in the narrow pore throats, others react by swelling in situ (smectite), and still
others react by readily dissolving in dilute acids and reprecipitating as secondary
iron compounds (chlorite). In general all clays adsorb chemical additives because
of their high surface area to volume ratio and the adsorbance capacity of this
surface (Almon and Da vies, 1981). The net result of these clay reactions is almost
always a drop in permeability, and hence a drop in production at the well bore
(Almon and Davies, 1981).
Mobile clay minerals are particularly abundant in sandstone reser
voirs, but they are also found in carbonate reservoirs as detrital grains or authi
genic precipitates (Hutcheon and Oldershaw,1985). There is a bias in the litera
ture of the last decade towards clay mineral studies of sandstone reservoirs.
(Clays in sandstone reservoirs are easier to extract than those in carbonates.) A
general misconception on the part of most workers in the field is that clays are
not important in carbonate reservoirs.
In a recent study by Hutcheon and Oldershaw (1985), it has been
shown that as little as one weight percent smectite in a carbonate reservoir can
significantly reduce oil recovery efficiency. Similar numbers are indicated for il
lite and kaolinite found by these authors in the same reservoir materials. These
clays will essentially react the same way during mercury imbibition testing, ie;
they will all create a similar fines migration problem leading to the plugging of
the narrow pore throats. In this sense it is assumed that a one weight percent
clay concentration hi a carbonate reservoir may cause problems in terms of oil
recovery efficiency if the clay is located in pore space and is granular in habit.
One weight percent clay would hardly affect recovery from a sand
stone reservoir so then what is the fundamental difference between the two li-
3
thologies? Why do clays play a more critical role in carbonates? The answer may
lie in basic differences in pore geometry. The idealized model of sandstone pore
geometry is that of pore space created between stacked billiard balls. This cre
ates rounded pore bulges and tube-like pore throats which can be conceptually
viewed as a periodically constricting tube (Dullien,1979).
The pore and pore throat network in carbonates, although much
more complex than that in sandstones, can be simplified to a bimodal size distri
bution consisting of large vuggy pores and finer intergranular (interparticle) pores
(Hutcheon and Oldershaw,1985). These pores in dolomites may be described as
polygonal or tetragonal depending on the degree of dolomitization, with pore
throats described as plate-like. The pore throats in carbonates are much narrower
than in sandstones, being in the order of less than one micrometer (Ward-
la w, 1979). They therefore are more susceptable to plugging by fines. This config
uration is significantly different from that in a sandstone. A schematic of the
types of pores in each reservoir is illustrated in figure 1.1. Examples of this type
of carbonate pore geometry can be found in appendix F, plates 15 and 20. These
SEM photos were taken of the dolomites in the pay zones of each reef studied.
Based on the above discussion, it seems reasonable that one weight
percentclay represents a suitable empirical boundary between situations.
Flow Direction 100 firn
Clays attached to pore walls
Clays in suspension
Clays plugging pore throat (after Khilar, 1973)
B
Pore Throats/ connections are Planer
Polygonal pore with clays
Tetragonal pore with clays (after Wardlaw, 1979)
10-50/xm
Figure 1.1: Schematic comparison of idealized sandstone (A) and carbonate (B) pore geometries
1.2 OBJECTIVES AND ASSUMPTIONS
The primary objective of this thesis was to investigate the clay
mineral content of three selected carbonate reservoirs in southwestern Ontario in
terms of its effect on oil recovery. In order to place the clay content in a scien
tific context, as well as an engineering one, use was made of basic principles of
carbonate sedimentology and clay mineralogy. The original study objectives were
as follows:
i) To define the clay mineral content in order to predict potential oil
recovery problems in the reservoirs studied. This involved defining
clay type (at least to the family level), habit, location (pore space or
matrix), possible origin (detrital or authigenic), relative amount, and
relative acid/water sensitivity.
ii) To investigate controls which depositional environment/fades may
have played on clay type, amount, or location. The definition of such
macroscopic relationships may aid in the rapid screening of well site
materials (core and cuttings) for horizons which may exhibit fines
problems.
iii) To study aspects of reef sedimentology which are related to oil re
covery in carbonate reservoirs. This includes qualitative observations
with regard to porosity, permeability and facies control on the reser
voir.
1.3 RESERVOIR SELECTION AND PREVIOUS STUDIES
1.3.1 Reservoir Selection
There are numerous carbonate reservoirs, ranging in age from
Cambrian to Devonian, on the Ontario side of the Michigan Basin. To attempt to
study all of the different reservoir types is outside the scope of this project. It
was therefore decided that two Silurian reservoirs, representing both a pinnacle
and a patch reef, would be chosen for the study.
The Silurian strata remain viable targets for oil and gas exploration
in the Michigan Basin. In 1981, 58.5 *fo of all exploratory tests conducted in Michi
gan were targeted for pay zones within the Niagaran Reef Belt (Bricker et al.,
1981). Silurian carbonate buildups, consisting of pinnacle and patch/barrier reef
complexes, provide excellent traps for hydrocarbons, especially since they are
encased by low permeability evaporites and carbonates of the Salina Formation
(Briggs et al.,1978).
In 1982 44.9 *?o of the total oil production and 36.1 % of the total
gas production in Ontario was derived from Silurian carbonate buildups (Habib and
Trevail, 1984). With this amount of attention being paid to Silurian carbonate
reservoirs in terms of exploratory drilling, production, and enhanced oil recovery
(numerous projects are underway in Ontario and Michigan), it seems only logical
that the Silurian should be the starting point for a clay mineral investigation in
the Michigan Basin.
The two reservoirs chosen were the Fletcher patch/barrier reef
complex, and the Wilkesport pinnacle Reef. Both of these reservoirs are st rat i-
graphically located hi the Middle to Upper Silurian Guelph Formation and A-1
Carbonate of the Salina Formation. (Stipled area in figure 1.2.) The re^fs are lo
cated in the Patch Reef and Pinnacle Reef Belts respectively, on the Ontario side
7
of the Michigan Basin (fig. 1.3). They were chosen on the basis of the availability
of complete core and sets of geophysical well logs.
SILURIAN STRATIGRAPHYIN THE STUDY AREA AND MICHIGAN
SYSTEM
UPPER SILURIAN
SILURIAN MIDDLE SILURIAN
1
SERIES
z
o
0
NIAGARAN
STRATIGRAPHIC UNITS
SALINA
RACTJ J AMABEL
TERMINOLOGY
STUDY AREA S.W. ONTARIO MICHIGAN
B UNIT
A2 UNIT
Al UNIT
* * 1 ' Y * * * ' ' * ". ' * 7 *\ . . - GUELPH* ". . -. y. - -i.* . -/\-*- - - - .* .: IX": I V-..\j . './ERAMOSA
GOAT ISLAND
GASPORT
ROCHESTER^^ S^X-s^X-X^"^ -
REYNALES
""V^x-^"^-. ~"^^-x^^*V.X^V^"
CABOT HEAD
B UNIT
A 2 CARBONATE
A2 EVAPORITE
At CARBONATE
Al EVAPORITE
* ' * " "- ' " " - '/~\ ' ' -'
' ' v^\* ' f ' \ ' ''. -^X "- : y^/- -' \V . * ' -.: - -- NI'AGARA'--*- - - - -'^
CLINTON
CABOT HEAD
FROM ONTARIO OIL AND GAS SUMMARY 1982 AND PEARSON (!980,M*c THESIS)
Figure 1.2: Silurian stratigraphy of the study area and Michigan
BOUNDARY BETWEEN PINNACLE REEF BELT (TO THE WEST) AND PATCH REEF BELT (TO THE EAST) (SANFORD, 1969)
Lake Eri*
20 40km
10 20
1:800000
3O miles
Figure 1.3: Location map
10
1.3.2 Previous Studies
An extensive literature search failed to reveal many references
with regard to the clay mineralogy of the horizons being studied. Some of the pa
pers obtained (Smosna and Worshauer, 1983) make indirect reference to clays or
argillaceous material within the reefs and associated strata, but only three papers
treat the specific clay mineralogy (Egbogah and King, 1984; Guillet, 1977; Miles
et al., 1985). It is this type of research that is vital for use in the design of fluids
which will limit formation damage during all phases of oil recovery (Almon and
Davies, 1981).
Egbogah and King (1984) in their discussion of enhanced oil recovery
considerations for Ontario refer to a confidential in-house clay mineral study
conducted by Amerigo Technology Ltd., in Calgary. Core samples from the
Guelph Formation were obtained from the Grand Bend and Warwick reefs. Addi
tional samples from the Salina Formation were obtained from the West Becher
Pool.
X-ray diffraction analysis revealed the presence of one weight per
cent clay minerals consisting of illite, kaolinite, and chlorite. The authors con
cluded that the assemblage of clay minerals did not have any effect on oil pro
duction from these reservoirs. They cite the successful waterflood on the West
Becher Pool as an example. No clay mineral studies were conducted on this reser
voir prior to waterflood.
Guillet (1977) published a study of the clay mineralogy of shales and
clay-rich tills in Ontario. He indicated that the Rochester Shale, which underlies
the Guelph reefs, contains small amounts of illite and chlorite, with illite being
the dominant species.
11A study conducted by Miles e t al. (1985) also shows the presence of
these two minerals plus kaolinite in the overlying shales of the Salina Formation.
One would therefore expect that the clay mineral assemblage present in the
Guelph Formation and the A-1 Carbonate may consist of these minerals if the de
trital source and diagenesis of these closely related beds is the same.
Another point noted during the course of the literature review,
which will be addressed in this study, is the paucity of studies describing the sedi
mentology of patch/barrier reef complexes. Many studies are available in the lit
erature describing the sedimentology, evolution, facies distribution, and diagene
sis of pinnacle reefs, but few papers are available on patch/barrier reef
complexes (Briggs et al., 1978). These reservoirs represent important exploration
and development targets in both Michigan and Ontario (Habib and Trevail, 1984).
This study and others (Smosna and Worshauer, 1983; Briggs et al., 1978; Shaver et
al., 1978; Meloy, 1974) indicate that significant differences exist between the
patch/barrier reef complexes and pinnacle reefs, and that further research is re
quired. Unfortunately it has only been recently that enough core was available for
study.
The cores from the Fletcher field represent the first opportunity to
study this reef type in detail in the subsurface in Ontario. Initial studies by Mar-
quez (1984) and Smith (1984) did not have the core which is now available, and to
the best of the writer's knowledge there have been no comparisons made between
this reef type and pinnacle reefs.
Major studies concerning patch reef growth during the Middle to
Upper Silurian have been conducted on outcrops in Ohio, New York, and West Vir
ginia (Kahle, 1978; Crowley, 1973; Smosna and Worsauer, 1983). All of these study
areas lie outside the Michigan Basin. The lack of detailed studies of the sedimen
tology and diagenesis of patch/barrier reef complexes in the Michigan Basin rep-
12
resents a major stumbling block to the design of an effective oil recovery project.
Knowledge of the materials to be encountered is necessary to develop the best
approach to enhanced oil recovery.
1.4 PERTINENT RESERVOIR INFORMATION
1.4.1 Fletcher Patch/Barrier Reef Complex
The Fletcher field is a large patch/barrier reef complex covering
22.66 km (5000 acres) in Tilbury East and Raleigh Townships, of Kent County
(Macqueen et al., 1985). The field has produced a total of 190,764.6 m 3
(1,200,481.6 bbls) of 380 to 410 API crude oil (Habib and Trevail, 1984) from two
separate horizons. The shallowest horizon, located at an average depth from sur
face of 410 m, is the upper Guelph-A-1 Carbonate non-reef net pay zone,a con
sisting of dolomitized A-1 Carbonate and the lagoonal facies of the Guelph For
mation (Ibid). The lower Guelph reef pay zone, found at approximately 420 m
below the surface, consists of the dolomitized eroded reef top and reef core fa
cies within the Guelph Formation (Ibid). Records show that the initial production
was obtained from vuggy-fracture porosity within the reef core, and that later
production came from the interparticle porosity within the overlying lagoonal/su-
pratidal drape of the upper zone (Macqueen et al., 1985). An estimated 2,400,000
m (15,096,000 bbls) of recoverable crude remains in place in these overlying
drape beds (Macqueen et al., 1985).
The field was first discovered in 1905, and was abandoned by 1919
except for a few minor producing wells (Koepke and Sanford, 1965). In 1981 Con
sumers' Gas took possession of the property and began a two year drilling program
targeted at defining enhanced oil recovery potential (Macqueen et al., 1985). A
total of 15 wells were drilled (11 of which were cored) and geophysically logged,
13
providing the necessary material for detailed geological and reservoir engineering
studies, including the present study. In the summer of 1984 the writer sampled
and logged 5 holes containing 62 meters of core. The locations of the cored holes
used in the study are shown in figure 1.4, which is an isopach map of the lower
reef net pay zone.
14
FLETCHER REEF:NET PAY ISOPACH 8 STUDYWELL LOCATIONS
l 2 miles
COURTESY OF S. COLQUHOUN, CONSUMER'S GAS
O 1 2 3 4 km
C.I. * 2m
Figure 1.4: Fletcher reef net pay isopach showing the location of cored holes used in the study
15
1.4.2 Wilkesport Pinnacle Reef
The Wilkesport pool is a much smaller entity than the Fletcher
field, covering only 0.844 km (208.55 acres) in Sombra Township, of Lambton
County (Macqueen et al.,1985). The field produced 567.3 m3 (3568.9 bbls) of
crude oil and 2,371,054 m of natural gas from numerous dolomitized horizons
within the reef itself (Habib and Trevail, 1984). Oil production was poor because
of limited porosity and permeability. The oil pay zone was acidized and frac
tured, but low flow rates forced the operator, then Imperial Oil Ltd., to plug the
holes in favour of uphole gas production (Stinson, 1978). The reef net gas pay
zone lies at a depth of 565 m from surface.
The pool was first discovered in 1965 by Imperial Oil Limited and
was converted for use as a gas storage facility in 1978 by Tecumseh Gas Storage
(pers. comm. R. Stinson, 1984). The tight anhydrite cap and A-1 carbonate off-
reef beds make this reservoir ideal for gas storage purposes.
It is unlikely that this reservoir will ever be subjected to any en
hanced oil recovery scheme because the pool has virtually no oil reserves left in
place and also due to the extremely low permeability in the oil bearing horizon
(Macqueen et aL, 1985). It does, however, represent a typical pinnacle reef and is
ideal for the clay content study because of the single core cut from I.O.E. Sombra
4-14-Xm, which penetrates the reef crest. In the summer of 1984 the writer
logged and sampled 118 m. of continuous core from this reef. The location of this
hole is shown as I.S. 4 in figure 1.5 (reef isopach).
16
r~WILKESPORT REEF ISOPACH
0.5
O GAS STORAGE WELL
-us OBSERVATION WELL
-ft GAS WELL
-f DRY X ABANDONED
COURTESY OF R. STIMSON . CONSUMER'S GAS
~l
TW6
J
2 km
1.0 mile
C.I. " 5O FEET
Figure 1.5: Wilkesport pinnacle reef isopach showing the location of all wells drilled into the structure. I.S. 4 is the core used
Chapter II
METHOD OF STUDY
2.1 DELINEATION OF FACIES
Before beginning the core logging phase of the project two field
trips were undertaken by the writer to study similar carbonate buildups in out
crop. A classical Middle Silurian patch reef was observed in outcrop on the 401
highway near Milton, Ontario. This reef contains all of the elements outlined in
previous papers on patch reefs, including the presence of a distinct reef core
flanked by crinoidal/brachiopod and reef debris beds (Kahle, 1978; Briggs et al.,
1978; James,1984).
The second Silurian reef visited, being much larger in areal extent,
better approximated that observed in the Fletcher field. A thick section was
studied at the U.S Gypsum Quarry in Genoa, Ohio. This well-exposed section
showed all of the classical reef growth features, including a crinoidal/brachiopod
base, reef core (consisting of stromatoporoids, tabulate corals, and pentamerid
brachiopods), and an overlying lagoonal/supratidal sequence (consisting of prima
rily algal stromatolites). Observations made in the field, although not included in
this paper, aided in the facies interpretations made on core.
Five cores, totalling 62 meters in length, were obtained for study
from the Fletcher field, and one complete core, totalling 116 meters in length,
was obtained from the Wilkesport reef. The cores were slabbed (axially) to facili
tate core logging and sample acquisition. They then were geologically logged and
over forty thin sections were cut and stained with alizarin red solution in order to
determine the facies distribution and degree of dolomitization in each reservoir.
- 17 -
18
The nature of the rock in both reservoirs presented separate prob
lems in terms of the core logging and facies interpretation. Extensive dolomiti
zation of the Fletcher field carbonates limited observations to macroscopic tech
niques such as the binocular microscope. With this, fossil remains and
sedimentary structures could be identified. The study of thin sections provided
very little additional information regarding facies, with the exception of those
cut from the green shale beds.
In the study of the Wilkesport reef, thin sections played a greater
role in the facies interpretation because of limited dolomitization. Macroscopic
techniques provided some information but were limited because the majority of
the section studied consists of extremely dark brown micrite, in which fossils and
structures are difficult to discern.
In addition to normal parameters obtained during core logging (fossil
type and relative abundance, sedimentary structures, lithology, etc.), notes were
made regarding stylolite type using the tentative classification scheme proposed
by Wanless (1984). He suggested that the amplitude and form of the stylolite is
directly related to the amount of argillaceous material in the original host sedi
ment. A relatively argillaceous sediment is observed to produce, by pressure solu
tion, numerous flat, low amplitude, or anastomosing stylolites. On the other hand,
a relatively clean sediment contains stylolites displaying very jagged surfaces
having high amplitudes. Naturally there exists a number of intermediate types
between these two end members.
These type of observations were collected to determine if stylolite
type can be used, in association with the gamma log, to define zones of higher
clay mineral content in core. This is assuming that the degree of pressure solu
tion is relatively consistent throughout a single horizon in the reservoir. It was
19
also noted during core logging that extremely argillaceous horizons (such as the
"green shale" or vadose silts in the Guelph Formation) always have a green tinge
to them due to concentration of clay minerals.
The detailed core logging was a vital phase of the project, as the
geological description provided the data to develop the facies interpretations and
a sampling scheme to study the clay mineral content.
2.2 SAMPLING, SAMPLE PREPARATION, AND ANALYSES
2.2.1 Introduction
The overall method used in the study of the clay mineral content of
the two reservoirs cannot be attributed to one author. The entire methodology in
corporates elements proposed by Almon and Davies (1981), Ostrom (1961), Ra ben-
horst and Wilding (1984), and by the Land Resource Sciences Department at the
University of Guelph.
2.2.2 Sampling and Sample Preparation
Sampling was conducted based on the facies distributions. It did not
seem geologically valid to sample at set intervals due to the heterogenous nature
of the core. It was felt that additional scientific information could be obtained
from a sampling scheme using at least one sample from each facies. Forty-three
samples, consisting of approximately 100 grams each, were obtained for the x-ray
diffraction study. Representative chips were retained from these samples for use
in the scanning electron microscope and KEVEX EDS studies.
The core was carefully washed to remove surface contaminants, and
then crushed using a shatter box system to obtain a final size fraction between 60
and 120 mesh (125 to 250 micrometers). This size fraction was recommended by
Ostrom (1961) to reduce the risk of damage to the clays during crushing. (Poten-
20
tial damage, as the result of excessive crushing, has been documented by Brindley
(1981).) The crushed sample material was then solvent extracted using chloro
form in a Soxhlet extractor unit to remove residual hydrocarbons which might
limit the effectiveness of the acid digestion process, or cause loss of resolution
on the x-ray diffraction trace.
In order to be able to identify the clay mineralogy using x-ray dif
fraction the clays had to be removed undamaged from the carbonate host to make
oriented mounts. Random powder mounts do not provide the resolution required
to study clay minerals in the concentrations that are present in the samples being
studied. (See figure 2.1.)
An acid extraction method, developed by Rabenhorst and Wilding
(1984) was slightly modified for use in this study. This method involved digesting
the samples for a period of up to four weeks in an acid solution, buffered to a pH
of 4.5 with sodium acetate. This digestion was found to effectively remove the
carbonate host leaving behind the insoluble residue containing the clay minerals.
Details of this method can be found in appendix D.
Although Rabenhorst and Wilding (1984) conducted some experimen
tation on the effect of their method on various clay minerals, further testing was
undertaken by this writer to be reasonably certain that the technique was not
causing biasing in the results from the samples studied. The clay samples selected
for the experiment represent some of the more acid sensitive clay species. How
ever, the results of the testing do not conclusively indicate that no biasing has
occurred. Differences between the structure and crystallinity of the clay sam
ples tested and those in the reservoir may be significant enough to effect the dis
solution rate and thus cause biasing. It is beyond the scope of this thesis to test
this method further.
21
The results do, however, indicate that the acid sensitive clay sam
ples used (iron rich chlorite and trioctahedral smectite) are not significantly af
fected by the acid treatment when they are in the presence of dolomite. It is
therefore reasonable to assume that the dolomite acts as an additional buffer.
Details of the testing can be found in appendix E.
The insoluble residue from the digestion process was dispersed in
an aqueous solution of sodium hexametaphosphate and centrifuged to separate the
clay from the silt size fraction. The clay size fraction was allowed to air dry and
then was split into two equal subsamples to be used in the two x-ray diffraction
mounts. One of the subsamples was treated with 0.5 M MgCl^, the other with 1.0
M KC1. These treatments were done in order to saturate the two subsamples with
Mg"1"1" and K"1" to aid in the clay mineral identification process. The two different
treatments create different lattice spacings in some clays, such as smectite. This
difference in structure is reflected in a difference in the d-spacing observed on
the x-ray diffraction trace. Subsequent treatments (if necessary) allow the opera
tor to discriminate among the clay minerals which may be present in the sample.
Oriented clay mineral mounts were created by pipetting suspended
samples onto glass slides and allowing them to air dry. This technique allows the
clays to sediment and orient themselves parallel to their long axis, providing the
maximum peak Intensity (Brindley, 1981).
22
X-RAY DIFFRACTIONRANDOM POWDER
MOUNTS
FLETCHER PATCH X BARRIER REEF COMPLEX
WILKESPORT PINNACLE REEF
l l l14 12 1O 8
DEGREES 29
Figure 2.1: Random powder mounts of samples from the Fletcher and Wilkesport reservoirs
23
2.2.3 X-ray Diffraction Analysis
The oriented clay mounts were analyzed using a Rigaku D-Max-EA
automated horizontal x-ray diffractometer, located at the University of Guelph.
They were analyzed from 3 to 14 degrees 2 theta, at a scan rate of 2 degrees per
minute, and at a rate of 800 cps.
The purpose of the x-ray diffraction study was to provide qualita
tive information regarding clay mineral content. An amount of clay in terms of
weight percent was not obtained from this analysis, only relative amounts of clay
in each sample could be inferred from comparing peak intensities. This, combined
with observations made on core, the intensity of the gamma log response, and the
amount of insoluble residue remaining after the digestion of the carbonate, al
lowed the writer to estimate the amount of clay minerals present in each facies.
The estimate is not subjective, but is qualitative in that a precise amount cannot
be stipulated, but relative amounts can be.
2.2.4 SEM/KEVEX Analyses
A detailed scanning electron microscope and KEVEX EDS analysis
was conducted on over 60 core chips from the three reservoirs. The scanning
electron microscope allows the user to observe the sample at higher magnifica
tions than conventional binocular microscopes. High resolution imagery can be
obtained even at several thousand times magnification, allowing direct observa
tion and photography of clay sized particles and the pore network geometry. The
KEVEX energy dispersive analyzer allows the operator to obtain a crude elemen
tal analysis of whatever is being shown on the screen of the SEM. The combined
use of the SEM and KEVEX provides a qualitative technique to determine the clay
mineral speciation (by habit,form and composition), relative abundance and loca-
24
tion (by physical observation of the matrix and pore spaces), and possible origin
(by habit and location).
One of the advantages of the SEM/KEVEX over the x-ray diffrac
tion is simple sample preparation. A freshly broken surface is created on the
core chip, which is then mounted onto an aluminum SEM stub using a quick drying
epoxy resin. Areas of the aluminum stub still exposed are covered with conduc
tive carbon paint to shield the effect the stub itself may have on the KEVEX. Tall
samples (greater than 2 mm in height) require that the sides be coated with the
carbon paint in order to ensure an even charge distribution on the surface of the
sample itself. The remaining exposed surface on the top of the sample is coated
with a 400 angstrom thick layer of pure gold.
The gold coating was found to be necessary to prevent charging on
the surface of the sample due to poor conductance. Gold provides an even con
ductive coating, allowing the user to obtain the best possible imagery. One
drawback of the gold coating is that it masks some of the peaks obtained from
the KEVEX EDS analyzer. Fortunately only sulphur and phosphorous are masked,
which are not important in the assessment of clay mineral content. Aluminum,
silica, potassium, and iron are the most important peaks used in the clay mineral
study. Calcium, magnesium, iron and sulphur are associated with the carbonates,
evaporites, and sulphides present in some of the samples.
Since the information from the SEM/KEVEX analysis cannot alway
be interpreted unambiguously the findings should be confirmed using x-ray dif
fraction (Almon and Davies, 1985).
Chapter III
RESULTS AND DISCUSSION
3.1 FACIES DESCRIPTION AND INTERPRETATION
3.1.1 Fletcher Patch/Barrier Reef Complex
This section contains a general description and interpretation of
each of the four fades/environments defined during the core logging phase of the
study. The facies succession is similar to that presented by Briggs et al.(1978) in
the study of reefs in Michigan, and to that described by Kahle (1978) in his study
of a similar reef complex near Maumee, Ohio.
Figures 3.1, 3.2, and 3.3 represent summaries of the core logging
results as compared with the gamma log response and facies interpretations for
Consumers' 33407, 40001, and 40003. Insufficient core material was available
from Consumers' 33323, and 40000 to warrant the drafting of log correlations for
these holes. However, samples from these cores were used in the study. The de
tailed core logs from each of these wells can be found in appendix A. Represen
tative core photographs of each of the facies can be found in appendix C,plates 4
to 8. (These will be referenced throughout this section by plate and picture num
ber.)
As stated previously, the facies of the Fletcher field can be divided
into two producing horizons, consisting of an upper Guelph-A-1 Carbonate non-
reef net pay zone and a lower Guelph reef pay zone (Macqueen et al.,1985).
The basal facies of the lower pay zone consists of a dolomitized
stromatoporoid-coral framestone. Frame-builders in this facies are tabulate cor
als, such as cladopora sp. (plate 7, no.2,3) and favosites sp. (plate 6, no.2), and
- 25 -
26
FLETCHER REEF —CONSUMERS 334O7
)EPTH ETRES)
423 ————
430 ————
435 ————
440 ————
443 ————
450 ————
LITHOLOGY
J fi /si 7.i*^yte/.*!^^./fSGtfJ/SftsJfal'tJ/ft O/ 0/00/ 0/ ft /tf
7/7^nr/viss y~ ~7"- y- /-ofr-/--
H fSL */ H i
fir li /JT^/IH*^Cfc / SI /©^o /y^/r/m TT/feie / -o- /^ m/
/O /O ^/Jtt/nrt/ 7"* /rtrt 7 m y^r /rt
O ^/O 7 3B ^m/H-*/ 9 /O rt^ m Aat/^reein/ /OTrOkrt /m / o /rt
rt/ rt / rt 7 mm/rt /rt / rt/m /rt /m /rt
7 n 7 rt 7ft//m/m/4^///rt/^m/'v/OrtS 7 S /r n/ n/in /M /rtrt/m/v /m / 0 x7/7
GAMMA (API)
0 15 SO 45 6O 75i l i l l
1Cf-—
4^ NODULES0 PELLET 0 PISOLITE
INTRACLAST ANHYDRITEDOLOMITE iSALT MFR.I
A ALGAL STROMATOP
FACIES/UNIT
1A-1 CARBONATE
PELLETAL WACKESTONE -GRAINSTONE AND ALGAL STROMATOLITE
•^~*- TOP GUELPH FM. ^~^ LAGOON X (WACKESTONE)
LAGOON/ ERODED REEF TOP FACIES
(STROMATOPOROID FLOATSTONE)
REEF TOP FACIES (STROMATOPOROID CORAL FRAMESTONE)
l
KEY
^P^
FILL f 7 fTRINGER/ PATCH
OROtO
ANH
LIM
OOL
^ CORALT BRYOZOAN
O CRINOK)n DEBRISO GASTROPODO OSTRACODET PELECYPOD
Figure 3.1: Facies and gamma log correlation for Consumers 33407
FLETCHER REEF - CONSUMERS 4000127
DEPTH (METRES)
~fcw
^
———— 430 ———
LITHOLOGY
n/n /e/ i^ 7 ^ /o* /~/B tt/^iO*^! O/^j /v ^/v n y ottL/ SK /B C^ ^v/v o/ B 7 1 y• /vo/v O/"S /l O/v B 1B B /^ B /^XB/^" ym^^ot/m/. i /a/B/ M A. M/ttl^ /a B/i nn//B/BBO^OO HB/ B /O ^ /OB /B A/V H/O B/ ^ H/0/a, m/B N
/B O /B O /B
0
i
GAMMA (API)
15 3O 45 60 75 i i i i i
1 tS z\ 7
\ CORE
3rx^\' ^
\ j) 1f 1
1yf^i
FACIES/UNIT
GUELPH FM.LAGOON/ (WACKESTONE)
LAGOON/ ERODEDREEF TOP FACIES(STROMATOPOROID
FLOATSTONE)
REEF CORE FACIES(STROMATOPOROIDuUrtAL rnAMtOlUNtJ
\ '
KEY
NomN.cs
o pisolite
O0
AMMYOmTC FitDOLOMTC STH1NCEW/PATCM
SALT MF&L
ALGALsinoMAiorowotoAMFinrOHA
COftAL
envozoAMCRINOID
OESfttS
GASTROPOD
OS1RACOOC
PELECYPOD
LIMESTONE
DOLOMITE
Figure 3.2: Facies and gamma log correlation for Consumers 40001
28
FLETCHER REEF - CONSUMERS 40003
DEPTH (METRES)
420
425
430
435
440
LITHOLOGY
II 7 O 7 H AA. /ntft/m
/o v/ m 7 HH/ ^ /m
/M
n ii/n a/o m n/ Hm/o
nr H/ m n/mM n 7 m
7 7
GAMMA (API)
0 15 3O 45 6O 75 i i i i i
coneGAMMA
FACIES/ UNIT
GUELPH FM. LAGOON/ (WACKESTONE)
LAGOON X ERODEDREEF, TOP FACIES(STROMATOPOROID
FLOATSTONE )
REEF CORE FACIES ( STROMATOPOROID
CORAL FRAMESTONE)
iKEY
0 •OT
O O
mMHa.es W.LET
INTRACLAST
ANHYDRITE FILL OOLOMTC STRINOCR/rATCM
SALT WTILL
ALGALSIROMATOTOftOIO
AMPtnrOMA
CORAL
BRYOZOAN
CRINOID
OF emsGASTROrOO
OSTRACODE
PELECYPOD
WM ANIITORITC
LIMESTONE
DOLOMITE
Figure 3.3: Facies and gamma log correlation for Consumers 40003
29
hemispherical, globular, and tabular stromatoporoid (plate 6,no.4;plate 8,no.l,3).
They are mostly situated in growth position. The inter frame-builder debris con
sists of crinoid, brachiopod, and coral fragments which give the sediment a dis
tinctive mottled appearance, making it discernable from the overlying facies
(plate 7,no.4).
Stylolites found in this facies are extremely jagged and have high
amplitudes which are indicative of an argillaceous-poor sediment according to
Wanless (1984). A typical stylolite from this facies can be seen in plate 2, photo
B, in appendix B.
The dominant porosity type in this facies is vuggy (plate 7,no.3).
Vugs ranging from pin point to fist size are interconnected by numerous subverti-
cal fractures. These porosity types account for the high permeability, yet moder
ate porosities (100-1000 md, 5-10 ?fc) in this unit and would not likely be affected
by fines migration as much interparticle porosity would because of gross differ
ences in the size of the pore throats.
Other porosity types noted include intraparticle/growth framework,
which are associated with the corals and the dolomitized stromatoporoids (plate
7,no. 1,2; plate 6, no. 2), moldic porosity, associated with brachiopods and pelecy-
pods, and very fine interparticle porosity. These make only a minor contribution
to the effective porosity and permeability and are generally partially filled with
gypsum/anhydrite and dolomite cements.
This facies is believed to represent a reef core environment as de
scribed by James (1984). In this horizon maximum faunal diversification and
growth occurred. Although faunal diversity was at a maximum in this unit there
appears to be no evidence of faunal succession or dominance. In any single level
in the reef a number of different frame-builders appear to co-exist. This lack of
30
faunal zoning is typical of both modern and ancient patch reef complexes (Crow-
ley, 197 3; Kahle,1978). For this reason no further subdivision of this facies was
undertaken.
The upper facies of the lower pay zone is a dolomitized stromatopo
roid floatstone. This unit consists of biological and mechanically eroded frag
ments of stromatoporoids which are scattered throughout a buff to dark brown,
sparsely fossiliferous mudstone/grainstone matrix (plate 5, no.4; plate 6 no.l).
Fossil debris in this wackestone matrix consists of crinoid ossicles, and pelecypod,
gastropod, brachiopod, and halimedes sp. and other coral fragments.
The upper contact of this unit is picked as the first appearance of a
stromatoporoid fragment and by a marked reduction in the number of large do
lomite-filled burrows. The bottom contact is picked at the first indication of
abundant faunal diversity associated with the frame-builders and and by the mot
tled appearance of the interframe-builder debris.
Stylolites found in this facies are identical to those found in the
reef core, but are fewer in number. Again the jagged form indicates a low argil
laceous content according to Wanless (1984). This is substantiated by the poor
gamma log reponse over this interval.
As in the reef core facies the dominant porosity type is vuggy. The
vugs are not as abundant as they are in the lower facies, but they are still inter
connected with subvertical fractures. Some of the vug-fracture systems in this
facies are partially filled with gypsum/anhydrite, lowering the overall permeabili
ty of this unit. Other minor porosity types present in this facies consist of intra
particle porosity (associated with the dolomitized stromatoporoid fragments),
shelter porosity (associated with the brachiopods), and interparticle porosity.
31
Oil production from this unit appears to have been associated with
the vug-fracture systems more than it was with the interparticle porosity (Mac
queen et al.,1985), therefore it is unlikely that clay minerals, if they are present
in this facies, would have any significant detrimental effects on the oil recovery
efficiency from this horizon.
This facies is believed to represent the death and erosion of the
reef core in a lagoonal environment. Evidence for this interpretation is as fol
lows. The presence of randomly oriented stromatoporoid fragments, which appear
to have been mechanically broken and bioeroded, at the top of the reef core fa
cies, is a physical indication that this erosion process may have taken place. The
sediment in this unit is distinctly different from that of the reef core facies.
Secondly, the facies succession observed indicates that this may be a classical
shallowing upwards sequence (as defined by James, 1984) with reef growth being
replaced by a lagoonal environment, which was in turn replaced by a supratidal
environment.
In modern reefs there is a delicate balance between destructive and
constructive forces (James, 1984). The destructive forces can be grouped as me
chanical (storms, waves, and currents) and biological (bioeroders, scavengers,
etc.). Normally, reef growth rate exceeds destruction rate and the reef continues
to grow upward until it shoals, however, the frame-builders are fragile organisms
which can easily be destroyed by an influx of terrigenous material, or by changes
in salinity and temperature (James, 1984). Both of these factors may have played
a role in the death of the Fletcher reef, allowing mechanical and biological fac
tors to create the unique sediment observed in this facies.
The lower facies of the upper pay zone is a wackestone. This unit is
characterised by a dark brown to buff dolomitized micrite with a minor amount
32
of preserved marine cement (plate 5, no.3) and abundant bioturbation in the form
of dolomite filled burrows (plate 4, no. 4). Fossils in this unit consist of scattered
gastropods, pelecypods, brachiopods, and an occassional nautiloid and coral frag
ment (plate 5, no. 1,2).
Stylolites found in this facies are the transitional forms described
by Wanless (1984). A photomicrograph of this type can be found in plate l and 2,
photo B, in appendix B. These types are believed to represent a changeover in the
amount of argillaceous material in the sediment (Wanless, 1984). This trend is in
dicated by the gamma log response hi figure 3.1.
Porosity types delineated include interparticle, moldic, and vuggy.
Subvertical fractures were noted in this facies but are generally gypsum filled
and too fine to contribute significantly to the porosity or permeability. The same
can be said of the moldic and vuggy porosity in this unit. This leaves interparticle
porosity as the dominant type. The reliance on this finer intergranular porosity
for the transport of fluids leaves this unit susceptible to possible formation dam
age if clays are present.
This facies is interpreted as representing a shallow water lagoon.
Evidence for this interpretation are abundant bioturbation, the presence of graz
ers such as gastropods, and its position in the shallowing upwards sequence.
The contact between the shallow lagoon facies of the Guelph For
mation and the A-1 carbonate of the Salina Formation is marked by a series of in
terbedded green shale and light buff dolomite beds, which provide a distinctive
gamma log response. (These beds were chosen as the datum for the Fletcher reef
correlation for this reason.)
These green beds consist of a number of fissile, laminated, silty
shales composed of clays (illite), dolomite, quartz, and sulphides. (This composi-
33
tion was determined from the observation of SEM/KEVEX, thin section, and x-ray
diffraction data contained in this thesis. See plate 3, appendix B; plate 22,23, ap
pendix F; x-ray trace 27F, appendix G; and plate 4, no. 3, appendix C.)
A subaerial exposure origin has been proposed for the beds at this
contact (Meloy,1974; Smith, 1984). Evidence for this interpretation are the pres
ence of possible karstic features, caliche, and pisolites. The green shale beds
have been interpreted to represent paleosols (Smith, 1984; Meloy,1974).
The upper facies of the upper non-reef net pay zone consists of the
pelletal wackestone/grainstone and algal stromatolite boundstone of the A-1 Car
bonate. This buff brown dolomite is virtually devoid of invertebrate fossils, pos
sibly the result of hypersaline conditions that are thought to have existed during
this time (Meloy,1974; Straw, 1985). Fossil evidence consists of abundant fecal
pellets (plate 4, no.2) and algal stromatolites (plate 4, no.l).
Stylolites in this unit are distinct from those found in the Guelph
Formation, in that they are generally flat and anastomosing. These Wanless (1984)
contends are an indication of a relatively argillaceous sediment. This hypothesis
correlates well with the gamma log response for this unit as seen in figure 3.1.
Examples of this stylolite type can be found in appendix B, plates l and 2, photo
A, and in appendix C, plate 4, no. 1,2.
The low porosity in this unit (average 5 percent) is attributed al
most entirely to interparticle porosity (Macqueen et al., 1985). Other porosity
types present in this facies consist of partially filled vugs, and fine subvertical
fractures. These latter types do not significantly contribute to the effective po
rosity or permeability which is generally less than 100 md in this unit (Macqueen
et al.,1985). If clay were present in the pore space of this unit they may affect
oil recovery efficiency by creating a potential fines migration problem in the fine
interparticle porosity.
34
This unit has been interpreted as a supratidal-tidal flat sequence
(Gill,1977;Straw,1983). The presence of flat pebble conglomerates, algal stroma
tolites, grainstones and its relative position with respect to the A-2 Evaporite
beds support this hypothesis.
3.1.2 Wiikesport Pinnacle Reef
The facies distribution in the Wiikesport pinnacle reef is complex
and exhibits distinct faunal zoning. These facies will be described in terms of the
three growth stages as outlined by Gill (1977). The stratigraphic nomenclature for
Silurian reefs in the Michigan Basin has been well established (Briggs et al.,1978).
For further details of each of the facies delineated in this study the writer sug
gests that reference be made to the rough core logs and thin section descriptions
located in appendix A and B, and to one or more of the excellent papers written
on these reefs (Gill,1977; Bay,1983; Balogh, 1981; Shaver et al.,1978; Briggs et
al.,1978, or Huh et al.,1977). These papers also provide more detailed descriptions
of the origin, sedimentology, and diagenesis of these reef than is feasible in this
thesis.
Figure 34 represents a summary of the core logging conducted on
LO.E Sombra 4-14-Xm as compared to the gamma log response and the facies in
terpretation. Representative core photographs of these facies can be found in
appendix C (plates 9 to 13) and will be referred to periodically in in terms of
plate and photo number.
The three stages of pinnacle reef growth in the Michigan Basin are
the biohermal stage, organic-reef stage, and the supratidal island stage
(Gill,1977). The biohermal stage, consisting of three facies (two basal debris
packestones and one calcarenite/grainstone) is completely dolomitized and rests
35
WILKtSPORT REEF-IOE SOMBRA 4-14- XIII
DEPTH (METRES)
—— 460 ——
—— 969 ——
—— 989 ——
—— 99O ——
—— 999 ——
——— 60O ——
—— 6O9 ——
—— 61O ——
—— 619 ——
—— 620 ——
—— 630 ——
LITHOLOGY
l
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f 70/^7 7' ; ' r^ 7 A 7 O 7 7
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GAMMA (API)
) SO K
VS
l"
f
H
FACIES X UNIT
O
A -2 ANHYDRITE
(NODULAR -CHICKEN WIRE VARIETY)
STROMATOLITE (SUPRATIDAL) WITH FENESTRAL POROSITY
STROMATOLITH: LENTICULAR STYLOLITES
BtOTURBATED PELLETAL 7 ALGAL WACKESTONE (LAGOON?)
ALGAL STROMATOLITE 7 VADOSE
FACIES
PELLETAL /ALGAL WACKESTONE
t• ••^^MI ii^ AMV*rllff*wVf A
\
CRINOIDAL WACKESTONE
ALGAL BOUNDSTONE?
BRYOZOAN/CORAL FLOATSTONE————— -^ AMPHIPORA
BRYOZOAN/CORAL FLOATSTONE
f CLAOOPORA FLOATSTONE
TABULAR STROMATOLITE (BOUNDSTONE)
TABULATE CORAL FLOATSTONE
BASAL DEBRIS (PACKSTONE)
irr^r^;' GRAINSTONE (CALCARENITE)
BASAL DEBRIS (PACKSTONE)
GOAT ISLAND FM (CRINOIDAL WACKESTONE)
T
KO
Oi
Figure 3.4: Facies and gamma log for I.O.E Sombra 4-14-XTH, Wilkesport pinnacle reef. Key to the symbols used found in figure 3. l
36
conformably on the more argillaceous crinoidal wackestones of the Goat Island
Formation (plate 13, appendix C). The facies of this stage are buff brown in col
our and consist primarily of fossil debris including crinoids, brachiopods, and soli
tary rugose corals (plate 12, no. 3). The calcarenite bed is fine grained with very
few recognisable fossil fragments (plate 12, no. 2).
Stylolites in these facies are jagged in form, which according to
Wanless (1984) indicates that the units are argillaceous-poor. These can be con
trasted with the stylolites found in the relatively argillaceous Goat Island Forma
tion below. There the stylolites are flat and anastomosing, giving the sediment a
lenticular appearance.
Porosity types in this unit consist of interparticle, pinpoint (plate
12, no. 2), vuggy (plate 12, no. 3), and intraparticle. The latter three types ap
pear to contribute very little to the effective porosity. Permeability in this unit
is consequently low (less than one millidarcy) making this unit too impermeable to
produce economic quantities of oil (Macqueen e t al.,1985).
The biohermal stage and crinoidal wackestone of the Goat Island
Formation represent the base on which the frame-builders of organic-reef stage
built (Huh, 1978). Sediment from the platform was transported to this position on
the slope where it was lithified in these bioherms, well below wave base
(Huh, 1978). These units represent the stabilization stage of James's (1984) reef
facies model.
The next stage of reef growth, and by far the most extensive in
terms of amount of carbonate deposition, is the organic-reef stage. Ten facies
were delineated that represent this stage. These extend from the tabulate coral
floatstone facies up to the pelletal/algal wackestone facies as indicated in figure
4.4. Dolomitization extends up to the middle of the bryozoan/coral floatstone fa-
37
cies where it dies out leaving a relatively unaltered limestone for the remainder
of the facies in this stage.
In terms of fauna this stage can also be divided into two sections.
The lower section fauna consist of frame-builders such as tabular stromatopo-
roids, including amphipora sp. (plate l, no. 2,3), tabulate corals, including favo-
sites sp., and solitary rugose corals (plate 12, no.l; plate 11, no. 4). Favosites sp.
is by far the dominant frame-builder in this reef. Interframe-builder debris con
sists of fragment of brachiopods, gastropods, rugose corals, and bryozoans.
In the upper part of this growth stage the fauna changes over to
mainly sediment binders, with algae being dominant. Ostrocodes and shell frag
ments are common in this part of the unit.
The upper part of the organic-reef stage is commonly known as the
Brown Niagaran Reef because of the presence of extremely dark brown micrite,
which is mottled with abundant marine cement, in some cases comprising 50 per
cent of the core (plate 11, no. 1).
Stylolites in the organic-reef growth stage consist of jagged to in
termediate forms as defined by Wanless (1984). The stylolite types in the Brown
Niagaran Reef are difficult to distinguish, even in thin section, due to the dark
nature of the sediment.
Interparticle porosity is the dominant form found throughout this
stage. Other porosity types delineated include intraparticle/growth frame work,
associated with the tabulate corals (plate 11, no. 4; plate 12, no. 1), pinpoint, and
vuggy porosity (plate 11, no. 1,2). These are partially filled with halite in the low
er part of this stage, and by selenite in the upper part.
This stage represents the period of maximum reef growth and may
be correlated with the colonization and diversification stage of James's (1984)
reef facies model. As conditions became more restrictive in early A-l Carbonate
38
time the fauna changed over from frame-builders to sediment binders. This stage
of reef growth was terminated by a period of subaerial exposure (Briggs et
al.,1978).
The next stage of reef growth is the supratidal island stage which
encompasses four facies extending from the top of the organic reef stage to the
base of the A-2 Anhydrite. These sediments are virtually devoid of invertebrate
fossils (due to high salinities) and consist primarily of partially dolomitized, buff-
grey vadose and algal stromatolite beds (Briggs et al.,1978). Algal stromatolites
in these facies consist of LLH and encrusting types (plate 10, no.3,4). The vadose
sediments are made up of zones of well developed caliche and vadose pisolites
(plate 10, no. 1) and flat pebble conglomerates (plate 10, no. 2).
Stylolites in the facies of this stage are flat and anastomosing, giv
ing the core a mottled/lenticular appearance in places. This stylolite type is indi
cative of an argillaceous sediment, according to Wanless (1984), which is substan
tiated by the gamma log response over this interval. (See figure 3.4.)
Porosity in these facies consists primarily of vuggy and fenestral
types (plate 9, no. 3) with interparticle porosity dominating in the dolomitized
sections. Although the porosity in some intervals is high (up to 24 percent) much
of this was infilled with gypsum/anhydrite. This horizon represents the zone of
maximum gas production (Stinson,1978).
The supratidal island stage of reef growth has been interpreted to
represent a period of intermittent reef growth during hypersaline conditions
(Briggs et al.,1978). It also may represent the domination stage of reef growth
described by James (1984). Periodically during this time the reef was subaerially
exposed allowing for the development of caliche and pisolite beds (Briggs et ah,
1978). Reef growth was finally ceased by the deposition of the A-2 Evaporite.
This created the impermeable seal on the reservoir and caused considerable dis-
39
placement of the algal stromatolites/caliche at the top of the A-1 Carbonate
(plate 9, no.l,2).
3.2 COMPARISON OF REEF TYPES
A general comparison of the two reef types studied in this thesis is
presented in table 3.1. A direct sedimentological correlation may not be possible
due to the differences in the environment of deposition. The Fletcher patch/bar
rier reef complex is situated on the platform/shelf margin, whereas the Wilkes-
port pinnacle reef is located on the slope of the Michigan Basin.
In addition to difficulties in correlation related to environmental
controls, the stages of the pinnacle reef growth are not time correlatives of those
in the patch/barrier reefs (Briggs et al.,1978). Pinnacle reefs, such as the Wilkes-
port pool, appear to have continued growing even after the patch reef growth was
terminated by either subaerial exposure, salinity chnges, or terrigenous influx
(Briggs et al.,1978).
fable 3.1 Comparison of the Two Reef Types Studied
Criterea Fletcher/Patch Barrier Wilkesport Pinnacle
Size
Shape
Location
Cap
Base
Facies Complexity
Degree of Dolomitiz ation
Pore Fill
greater areal extent (22.7 km2 )limited vertical extent
(45 meters thick)
irregular
shelf/platform in Patch Reef Belt
A-l Carbonate
crinoidal wackestone, Goat Island Fm.
simple, little faunal zoning
completely dolomitized
gypsum/anhydrite fit dolomite
Perceived exposed periodically atDegree of top of Guelph 4 intoSubaerial A-l Carbonate.Exposure (Well developed paleosols)
Limited areal extent (0.84 km2 )
greater vertical extent (greater than 120 meters thick)
regular - ovoid
slope, in Pinnacle Reef Belt
A-2 Anhydrite (A-l carbonate flanks reef facies)
crinoidal wackestone, Goat Island Fm.
complex, distinct faunal zoning
partially dolomitized (at top and bottom only)
Halite in lower half Selenite in upper, calcite throughout
exposed during supratidal island stage of reef growth (no paleosols)
50
41
3.3 CLAY MINERAL CONTENT
As previously stated, in order to determine the nature of the clay
minerals and how they will possibly affect oil recovery efficiency a few charac
teristics must be defined. These include: type, habit/origin, relative location, and
relative abundance. From these observations water/acid sensitivity and behavior
of the clays can be predicted. These parameters were obtained using a number of
different techniques including SEM/KEVEX, x-ray diffraction, and whole rock
geochemistry. No single technique provides all the necessary information.
Representative SEM photomicrographs and KEVEX traces are locat
ed in the front of appendix F of this report. The remainder of the KEVEX data is
located in the rear of this appendix. The x-ray diffraction traces for all of the
samples can be found in appendix G, and the weight percent insoluble residue data
(amount of clay-size insoluble residue remaining after acid digestion) can be
found in appendix H.
The results of the combined SEM, KEVEX, and x-ray diffraction
studies indicate that a monominerallic assemblage of illite is present in both res
ervoirs. These observations were further substantiated by a chemical analysis per
formed on illite physically extracted from the "vadose silt" of Consumers' 33323.
Clays were delineated on the SEM by their granular/flakey habit and
analyzed using the KEVEX to determine their approximate elemental composi
tion. KEVEX EDS traces, like the one found in plate 21 of appendix F, indicate
that the clay minerals observed are either illite or muscovite, by the relative rat
ios of the Al, Si, and K peaks (Welton, 1984).
The results of the SEM/KEVEX study were confirmed by the x-ray
diffraction. A ten angstrom peak was noted in 36 of the 43 samples analyzed.
The remainder of the samples exhibited no peaks whatsoever. (See x-ray diffrac-
42
tion traces in appendix G.) This peak is interpreted to be illite, although it does
correspond with a number of other clays of the same family (muscovite, glauco
nite, etc.).
A geochemical analysis of the illite physically separated from the
"vadose silt" supports this interpretation. (See table 3.2, potassium and iron
data.)
The potassium oxide values for this sample are too low for it to be a muscovite,
and the iron oxide values are too low for it to be glauconite (Grim,1958; Car
roll, 1970; Brindley and Brown, 1980). Dilution of the illite in this sample by other
minerals is considered to be negligible. This was concluded from the results ob
tained from an x-ray diffraction analysis of the sample from 3 to 75 degrees 2
theta (figure 3.5).
Two further tests were conducted on the "vadose silt" physical sepa
rate to determine if the sample contains any interstratified clay minerals. First,
the sample was re-analyzed using x-ray diffraction at a slower scan rate (one
quarter of a degree 2 theta per minute). This was done in order to determine if
the apparent peak between 3 and 6 degrees 2 theta was masking any clay mineral
peaks, or if it is due to x-ray scatter. The latter was found to be the case.
Secondly, the sample was glycol solvated to determine if randomly
ordered interstratified clays, potentially associated with the 10 angstrom illite
peak, are present. (See figure 3.5 for results.) No change in the peak parameters
(intensity and d-spacing) were noted, indicating that there is no more than 5 per
cent interstratified illite-smectite in this sample. It is not possible to define how
much is present, if any, in concentrations less than this (Sroden and Eberl,1984;
Brindley and Brown, 1980).
TABLE 3.2 Illite Whole Rock geochemistry - "Vadose Silt" Sample From Consumers f 33323
Sample K^O
Illite-1 6.16
Illite-2 6.18
Fe0* Ca0 Mg0 A1203 **
2.76
2.18
1.31 2.53 (13.57)
0.88 1.95 (13.25 )
Average 6.17 Illite 6,
2.76 1.10 2.24 (13.41)
* Iron species not differentiated during analysis (ie: is total Fe)
** Aluminum analyses are not accurate due to errors in wet chemical -
Atomic absorption method used. The AA is not sensitive to aluminum
as it is to the other elements, thus an error was introduced^
lO
h-
O*
CMN.— (/)
UJ Ulcr m o~~ uj o
S3
CVJ
in cu
h-CM
aoOS o(4
*4-l
r*4atow O13 rt
c*M O
MVo (tf
a ow* 4** O
2
44
45
Although biasing due to the dissolution of acid sensitive clays in the
reservoir rocks being studied cannot be ruled out, the evidence from the analysis
of the "vadose silt" does substantiate the hypothesis of a monomineralic illite as
semblage.
The illite detected in both reservoirs appears to be predominantly
detrital in origin. This is indicated by its granular-flakey habit as seen on the
scanning electron microscope (plate Z l,22, appendix F). Detrital clay generally
exhibit granular habit, whereas authigenic clays are generally well formed crys
tals with distinctive shapes (Welton, 1984).
The location of the illite, as determined from SEM/KEVEX and thin
section studies, further supports a detrital origin. The illite was predominantly
found scattered throughout the matrix, and is concentrated in stylolites, "vadose
silt" seams, and in the green shale at the top of the Guelph Formation (plate 2,
appendix B; plate 16, appendix F). Rarely was it noted to be present in the pore
space (plate 17, B,C; plate 24, appendix F). It would therefore appear that the
clay was primarily deposited along with the carbonate sediment and is not likely a
diagenetic product. It is beyond the scope of this thesis to further substantiate
this interpretation for this would involve the use of crystallinity indices such as
those proposed by Sroden and Eberl (1984). In terms of its behavior in the reser
voir, only the habit, basic mineralogy, and grain size are required (Hower,1974).
The source of the detrital illite is uncertain. It may have been de
rived from the weathering of rocks on the Canadian Shield, with rivers transport
ing the clays into the cratonic sea which existed at this time. Factors controlling
the observed clay mineral assemblage in these reservoir rocks may be source,
changes or sorting during transport, or post burial diagnesis.
46
It is unlikely that the source of the clay would be monominerallic. It
is more probable that changes which may have taken place in the clay mineral as
semblage during transport, such as chemical alteration or sorting (due to differ
ential flocculation or settling), may have contributed to the final observed assem
blage (Gibbs, 1977). The assemblage may have also been altered further by burial
diagenesis of the clays involving illitization of minerals such as smectite or mus
covite (Dunoyer de Segonzac,1970).
The relative amount of illite in the two reservoirs studied was esti
mated to be generally less than one weight percent. This was inferred using a
qualitative comparison of the x-ray diffraction peak intensities of the samples
with that of the "vadose silt" in figure 3.5 (known to have a sample weight of 50
mg). Although peak intensity on x-ray diffraction traces cannot be used quantita
tively as a measure of abundance (due to variability in crystallinity, mounting
technique, etc.), qualitative observations, coupled with data regarding the weight
percent of clay sized insoluble residue (appendix H) allowed the writer to esti
mate the clay content in terms of weight percent. Even a large error in the inso
luble residue data would not raise the weight percent values above one percent.
In general, it was noted that the illite is relatively more abundant in
the A-1 Carbonate and lagoonal facies of the Fletcher field than it is of the reef
core facies. Likewise in the Wilkesport pinnacle reef, the clay content appears to
be slightly higher in the supratidal island stage facies and in the Goat Island For
mation, than it is in the organic-reef or biohermal stage facies. These interpre
tations were based on a comparison of the gamma log response, stylolite type (af
ter Wanless,1984), KEVEX/SEM, x-ray diffraction, and insoluble residue data
refered to in the text and found in the appendices.
This comparison is presented in table 3.3.
Table 3.3 Location of Illite in the Two Silurian Reservoirs*
A. Fletcher Patch/Barrier Reef
Gamma Log Response/ KEVEX l SEM Stylolite Type
X-ray Diffraction Weight % Clay Size In Insoluble Residue
-A-l Carbonate-Green Shale-Wackestone-Stromatoporoid Floatstone- (decreases down ward)
-wackestone (25, 26,01-48,01-58, 01-51)
-stromatoporoid floatstone (29, 42)
-coral-stromato- poroid frame stone (43,40)
•A-l Carbonate-green shale (25 26,27)-stromatoporoid floatstone (37)•coral-stromatop- oroid framestone (32,33,40)
All analyses indicate amounts to be less than one weight %
B. Wilkesport Pinnacle Reef
Gamma Log Response/ KEVEX/SEM Stylolite Type
-supratidal island Facies-Goat Island Fm.
-supratidal island facies (5,7)
-Goat Island (22)
X-ray Diffraction
-supratidal island (2,7,9,12)-organic-reef (15)-Goat Island (21, 22)
Weight % Clay Size in Insoluble Residue
All analyses indicate amounts to be less than one weight %
* Table contains a list of facies where significant amounts of clays were detected. The numbers beside each facies indicates the sample numbers. The raw data can be found in figures 3.1 to 3.4 and in the appendices.
To make use of this table simply refer to the reef (Fletcher or Wilke- port) then to the method of study (SEM, x-ray diffraction etc.) and a list of the facies where the clays were found in abundance can be noted for each method.
48
In this table, the facies containing significant amounts of clays, as defined by
each of the techniques, are listed for each reef along with the sample numbers.
Samples from the reef core facies of the Fletcher reef, which contain significant
clays may contain a number of stylolites. These are believed to be anomalies be
cause the gamma log response and stylolite type logs do not indicate that there is
a concentration of clays in this horizon.
If the amount of the granular detrital illite had been greater than
one weight percent, and if it were located in the fine interparticle pore space,
then the illite would represent a fines migration problem, which could perhaps be
prevented through the use of clay stabilizers (Almon and Davies, 1981). However,
the amount and location of the illite in the two reservoirs studied would not likely
present any problems in terms of oil recovery. The successful waterflood con
ducted on a similar reservoir, the West Becher Pool, supports this conclusion. No
fines migration problems were encountered (Egbogah and King, 1984).
Chapter IV
CONCLUSIONS
The following conclusions can be drawn from this study:
i) A monomineralic clay mineral assemblage, consisting of illite, was
defined in all facies of both reservoirs. The clay was found scattered
throughout the matrix/cement, and was only rarely noted in the pore
space in any sample. The illite was observed to be concentrated in
stylolites, vadose silt seams, and in the "green shale** at the top of
the Guelph Formation. The majority of the illite appears to be detri
tal in origin. This was mainly determined by the habit as seen on the
SEM.
ii) Clays appear to be slightly more abundant in the lagoonal environ
ments of the Guelph Formation, the green shale, and in the A-1 Car
bonate of the Fletcher reef than they are in the reef core environ
ment. In the Wilkesport pinnacle reef it appears that the clay
mineral content is higher in the facies of the supratidal stage of reef
growth and in the underlying Goat Island Formation, than it is in the
organic-reef and biohermal stages.
iii) The amount and location of the illite negate the possibility of a fines
migration problem existing in either of the Silurian reservoirs.
iv) The sedimentology of the patch/barrier reef complex studied differs
significantly from that of the pinnacle reef. Not only is the former
much larger than the latter, but the facies distribution is simpler,
and there appears to be no faunal zoning in the reef core. Since
-49 -
50
patch/barrier reef complexes historically have produced significant
amounts of oil and gas, and since the two reef types do differ some
what, further work should be done.
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Appendix A
APPENDIX A - ROUGH CORE LOGGING RESULTS
-62 -
APPENDIX A ROUGH CORE LOGGING RESULTS
This appendix contains the notes from the geological logging
phase of the project. The depths indicated in these notes differ
from those used in the summary diagrams in the text because those
used here represent actual core depth measurements, whereas those
used in the final diagrams have been corrected to "true" depths
using a geophysical log correlation technique. This technique in
volves the use of a distinctive marker bed, such as a shale or
anhydrite unit, to correlate the core to the log response. It is
used due to errors inherent in the acquisition of the core depths.
The marker unit used in the correction of the Fletcher Reef cores
(Consumers' 33323, 33407, 40000,40001,40003) was the shale at the
Guelph Formation - A-l Carbonate contact. The bottom of the A-2
Anhydrite and the top of the Goat Island Formation were used as
marker horizons for the correction .of the Wilkesport Reef core
(I.O.E. Sombra 4-14-XIII).
The original measurements, including the units (feet or meters),
have been recorded to allow other researchers to make direct comp
arisons with core itself.
Well Name: Consumers' 33407 Field: Fletcher Reef
Unit Observations
A-1 Carbonate A14.84 - 415.06
415.06 - 515.65
415.65 - 415.94
415.94 - 416.09
416.09 - 416.54
416.54 - 417.00
A-l Carbonate 417.00 - 419.60
Guelph Fm. 419.60 - 420.00
420.00 - 421.00
421.00 - 423.00
64
coarse pelletal mud with no fossils,
few stylolites, dolomite, crude fin
ing upwards sequence
pelletal mud, ripup structures, not
as grainy looking as above, numerous
flat low amp. stylolites, algal
Algal stromatolites, green shale bed
at 415.63 m, spot pore fill of gyp.
stylolites numerous and low amp, flat
second green shale bed at 415.95 m,
very few other stylolites, fenestral
porosity? pelletal?
algal and pelletal mudstone dolomite
bioturbation, mud cracks filled with
gyp-* pinpoint porosity, low amp. sty
lolites scarce
pelletal mudstone,dolomite, wht. gyp
fills pinpoint porosity and fractures,
low amp. "horsetail" stylolites
pelletal mudstone, dolomitized, lg. nod.
of gyp., flat low amp. stylolites
Contact with Guelph Formation picked at
major stylolized, pyritized green shale
bed, subverticle
flat stylolites change over to jagged
forms in this dolomitic horizon, no
shale, blotchy dolomite, bioturbated
zone begins with 6 cm thick green shale,
mostly vuggy dolomite with ghost fossils
and verticle fractures,stylolites low
amp. jagged forms, gastropods
Well Name : Consumers 1 33A07 Field: Fletcher Reef
Unit Depth (m) Observations
Guelph Fm. A23.00 - 424.00 dolomite with ghost grains,gastropods
with intraparticle por., subverticle
fractures, green argillaceous zones,
ripup structures, scour, moldic and
vuggy porosity evident, pelecypod
fragments throughout, mod intergranular
porosity, Minor marine cement)
424.00 - 427.54 ghost grain dolomite continued, vuggy
and moldic porosity, some infill with
gyp-j pelecypoda and gastropod frags,
subverticle fractures, rugosa fragment
very few stylolites, jagged forms domin
ate, bioturbated.
427.54 - 430.89 coarse, buff, vuggy dolomite with numer.
stromatoporoid fragments (broken and
bored), crinoid ossicles, pelecypod frag
partial vug fill with gyp., subvertical
fractures, few stylolites but jagged ,
high amplitude
430.89 - 433.00 Reef core fauna, in situ forms including
tabulate corals, stromatoporoids as
frame-builders, abundant fossil debris
including pelecypods, crinoids, gastro
pods, halimedes, coral fragments. Vuggy
some with drusy lining others filled with
gyp. no visable bioturbation, jagged styl
433.00 - 438.00 Similar to above frame-builders include
lenticular, hemispherical, and globular
stromatoporoids, and tabulate corals,
interframe-builder debris includes: crin
oids, rugosa, halimedes, pelecypods, and
O O gastropod fragments, zones of vuggy porr
Well Name: Consumers' 33407 Field : Fletcher Reef
Unit
Guelph Fm.
Depth (m)
438.00 - 445.42
Ob servat ions
More reef core material with similar
frame-builders and reef core debris
as above, not able to zone this,some
very large in situ globular and hemi
spherical stromatoporoids, large in
situ rugosa coral, subverticle fract.
vuggy in spots with infill of gyp.
Stylolites jagged and moderately abn't
(10 per meter) Reef core debris creates
mottled appearance
66
Well Name: Consumers 1 40001 Field: Fletcher
Unit Depth (m) Observations
Guelph Fm. 419.20 - 421.11 highly mottled dolomite with num.
small and large vugs, fossil fragments
include crinoid, coral, nautiloids,
pelecypoda, abundant, some pores infilled
with gypsum, large subverticle fractures,
stylolites mod-high amp.
421.11 - 422.33 very fossiliferous pelecypod, gastropod,
coral wackestone, with marine cement, gyp
filled vugs and pores, stylolites jagged
and intermediate forms, minor strom, frags
subverticle fractures, rubble at base of
interval due to cavernous porosity zone
422.33 - 430.72 large abundant stromatoporoids fragments
1st real sign of these, tabular-laminar-
globular forms, pelecypods, gastropods,
crinoids make up debris, vuggy in spots
partially infilled with gypsum, numerous
subverticle fractures, stylolites jagged
and have high amp., halimedes and tabulate
coral frags also present, some marine
cement, some evidence of internal sediment
at 430.00 m
430.72 - 438.30 Large in situ frame-builders begin, inclu.
globular, hemispheical stromatoporoids,
tabulate (Favosites) corals, rugosa corals,
highly fractured and vuggy, with anhydrite-
gypsum fill, debris is mottled and consist
of crinoids, shell, coral and strom frags,
stylolites jagged and high amplitude. Brach-
iopods are found towards the end of the
core. No species appears to dominate67
Well Name: Consumers 1 40000 Field: Fletcher Reef
Unit
Guelph Fm.
Depth (m)
434.54 - 435.07
435.07 - 435.80
435.80 - 436.27
Observations
vuggy and intercrystalline por
osity, filled with gyp.,fine frac
tures, glob, stroms., jagged styl-
olites
very vuggy with lg. open fractures
lined with dogtooth sparry dol. flame
structure of green shale, fractures
gyp. filled, green bands below this
less vuggy and fractured, mottled
interframe-builder debris
Well Name: Consumers' 33323 Field: Fletcher Reef
Unit Depth (m) Observations
Guelph Fm. 432.20 - 432.98 top half of section has good intrap
article porosity in stroms. some sel
enite filled, fn. subverticle fractures
Bottom portion of interval vuggy and
anhydrite filled, some have internal sed,
68
Well Name: Consumers' 40003 Field: Fletcher Reef
Unit ' Depth (m) Observations
Guelph Fm. 425.95 - 427.58 homogeneous buff brown dolomite, no
abundant fossils occ. pelecypod, brach,
gastropod?, dolomite and anhydrite cement
in vugs, stylolites high amp. and jagged
some fn. subverticle fractures
427.58 - 435.22 First occur, of stromatoporoids, laminar
and globular forms with debris in between
pentamerids provide both intraparticle
and shelter porosity, stylolites jagged fc
high amplitude, some vug infill with gyp.
Favosites Sp. and pelecypod make up other
debris, fn. subverticle fractures,
435.22 - 438.00 True reef core fauna, dominated by strom
atoporoids tabular and globular forms, also
some tabulate corals, rugosa, halimedes,
and shell debris, fn subverticle fractures,
some mottling due to marine cement ( now
dolomite) stylolites jagged and high amp
appear to weave in and out of grains
some vuggy porosity, but lots filled with
dolomite and gyp.
69
Well Name: I.O.E. Sombra 4-14-XIII Field: Wilkesport Pinnacle Reef
Unit Depth (ft) Observations
A-1 Carbonate 1838.3-1865
A-2 Anhydrite 1818 - 1838.3 lg nod. anhydrite-gray-blue, with argill.
stringers - ripup structures which could
be caliche or algal stromatolites
chicken wire texture in some spots
dolomite with fine pinpoint and fenestral por
osity, algal stromatolites and laminations,
infill with gyp., heavily stylolitized, bottom
part of zone show a lenticular feature, algal
and pelletal
heavily bioturbated dolomite with -burrows in
filled with buff brown calcite, porosity poor
and pinpoint
Brown bioturbated limestone, pelletal-algal,
heavily stylolitized and nodular in appearance
abundant pinpoint porosity
bioturbated horizon burrows evidenced by light
buff infill poor to mod. pinpoint porosity,
ostracode bed
LLH and laminated algal stromatolites, zones
of flat pebble conglomerates, pellets and cal
iche in abundance
dark brown black wackestone, sparsely fossilif-
erous, limestone
abundant ostracodes, minor shell debris incl.
gastropods, brachs. heavily mottled with marine
cement (AO-50%)
Amphipora facies, abundant no other fossils
back to dark brown wackestone, abunt ostra
codes, minor marine cement (less than
bioturbation in spots.
1865-1873.2
1873.2-1887
1887- 1894.6
1894.6-1920
1920-1947
1947-1970
1970-1971
1971-1987
70
Well Name:I.O.E. Sombra 4-14-XIII Field: Wilkesport Pinnacle Reef
Unit Observations
A-l Carbonate
Guelph Fm.??
1987-1989 very grainy, lots of debris consisting
of shells, ostracodes, pellets, etc.
1989-1998.8 dark brown micrite with marine cement, first
tabulate coral frag at 1895.5 feet SO-60%
marine cement
1998.8-2001 tabular/encrusting stromatoporoid very thin layer
less than 2 cm, coral floatstone begins, vuggy
partially infilled with selenite, grainstone
with lots of marine cement surrounds coral frags,
more amphipora in lower part of the zone
2001-2006 Amphipora and crinoids and tabulate corals, the
latter is most abundant
2006-2006.9 good enlarged pinpoint porosity j debris and fine
algal filaments
2006.9-2013.5 dolomitized from 2008 feet down,crinoids,algae,
coral frags, brachiopods?, good pinpoint por
osity
2013.5-2018 large in situ tabulate coral fragments in dark
brown micrite with marine cement patches,halite
2018-2020.5 Feathery bryazoan colonies in dark brown micrite
2020.5 -2032 abundant marine cement in dark brown micrite,
minor bioturbation, some algal structures??
2032-2038 tabular stromatoporoids in amoungst marine cement
crinoids and debris, halite porefill
2038-2043 tabular stromatoporoids fragments
2043-2054 coral framestone with abundant favosites sp.
salt plugged, some tabular stroms., interframe-
builder debris, grey dolomite
71
Well Name: I.O.E Sombra 4-14-XIII Field: Wilkesport Pinnacle Reef
Unit Observations
A-1 carbonate
Guelph Fm.?
Goat Island
Fm.
2054- 2063.7 Basal debris unit, pellets crinoids, stylo-
lites jagged but few
2063.7-2066.3 calcarenite, dolomitic sand, fossil poor
2066.3-2080.2 debris including rugosa, crinoids, shells
salt plugging, dolomitized, and evidence
of solution breccia
2080.2-2125 highly stylolitized wackestone, flat-wavy
stylolites, argillaceous brown dolomite,crinoid
debris, bioturbated, greys and becomes nodular
towards bottom of the core.
72
Appendix B
APPENDIX B - THIN SECTIONS
73
Appendix B Thin Sections
Thin sections were obtained in order to determine facies relations
in the Wilkesport Pinnacle Reef. The relative lack of diagenesis
to this reef enabled the writer to observe textures, cements, poro
sity, and fossils.
Thin sections from the Fletcher Reef did not provide the same type
of information due to repeated diagenetic events which all but oblit
erated the original characteristics of the sediment. Valuable inform
ation was, however, obtained from the macroscopic examination of the
core. These observations provide the sole basis for the facies inter
pretation provided in the text of the thesis. Descriptions of the 17
thin sections obtained from this reef are not included in this appendix
for this reason.
A complete list of the thin sections studied and descriptions of those
from the Wilkesport Pinnacle Reef may be found on the following pages.
The thin sections were stained with alizarin red solution to determine
the degree of dolomitization. Porosity terms are those proposed by
Choquette and Pray,1970. Pore fill and constituents were interpreted
using thin section photos from standard literature.
74
Appendix B Thin Sections
Wilkesport Pinnacle Reef
Thin Section No,
A355A910A911A857A856A853A859A912A860A861A862A913A915A863A914A864A865A866A921A920A916A917A918A919
561.87566.93570.28570.94574.19577.77578.71580.77585.99588.72590.07595.58597.41598.20600.15601.29605.26609.22609.45611.28611.43611.73611.86611.89
Depth (m) Facies
Stromato!i tic Stromato!i tic Bioturbated Algal/ Pell. Wacke,
Algal Stromatolite/Vadose
Pelletal Algal
Amphipora
Algal Boundstone? Bryozoan/Coral Floatstone Amphipora Bryozoan/Coral Floatstone
1 5
Thin Sections con't
Thin Section No. Core Depth (m)
12
34567891011121314
3340733407
334073340733407334073340733407334073340733407334073340733407
424.38426.42
427.36429.79430.93431.00431.49432.69433.37435.27435.44436.56442.49443.60
Facies
Lagoonal/ (wackestone) Eroded Reef Top
Eroded Reef TopII M
Reef Core (strom.-coral M i, framestone)
1197A 1201A 1393A
33406 33409 33408A
427.38412.10417.08
A-l Algal "Green Shale" "Green Shale"
Mr. Jeff Meadows in his B.Se. thesis of this same year has other thin sections, (Fletcher Field) A complete listing of which may be found in his paper.
76
Slide - A855-1 Depth - 561.87 m
A. Fossils - Fossils appear to be absent
B Allochems - i) Pellets - none
ii) Spar - 100 -200 micrometers mostly dolomite 20%
iii) Micrite - remnant, S-10% patchy between spar
C. Stylolites/Clay Seams -
very thin,barely visable
D. Dolomitization - 85 - 95 35 , patchy with small amounts of calcite
100 -200 micrometer rhombs, well formed
E. Porosity - intercrystalline dominant, some fenestral
F. Cement - absent (none visable)
G. Pore Fill - 5 -10 % Gypsum (some may have been removed when cut)
Slide - A910-A
Depth - 566.93 m
A. Fossils - absent, apparent algal laminations evident when thin sect-
is examined macroscopically
B. Allochems - i) Pellets - none
ii) Spar 100 to 200 micrometers, 50- 60 %
iii) Micrite remnant less than 7%,patchy to intergranular
C. Stylolites/Clay seams - absent to very faint and flat
D. Dolomitization -50-60 55, patchy, rhombs 50 -100 micrometers well
formed and interlocking
E. Porosity - High intercrystalline
F. Cement - absent
G. Pore Fill - 30 -40 % gypsum, minor halite (cubic crystalline)
77
Slide - A911-B
Depth - 570.28 m
A. Fossils - broken mollusks, brachiopods infilled with coarse and fibrous
calcite and gypsum
B. Allochems - i) Pellets - 5-10 % relect altered to pseudospar
ii) Spar - less than 100 micrometers 80 %
iii) Micrite - remnant, S-10%, intercrystalline, patchy
C. Stylolites/Clay Seams - very thin, flat - horsetail
D. Dolomitization - 40-50 % patchy with stringers, rhombs 50 to 100 micro
meters, well formed
E. Porosity .- Moldic in peleypoda, mod - high intercrystalline
F. Cement - Minor, S-10%, coarse calcite void fill and apparent fibrous
marine cement
G. Pore Fill - 5-10 Z gypsum vug and intercystalline pore fill
Slide - A857-3
Depth - 570.94 m.
A. Fossils - pelecypoda shell fragments filled with dolomite, ostracodes?,
deformed crinoid ossicles, weak algal laminationl filaments
B. Allochems - i) Pellets - relict and abundant between grains
ii) Spar - 90% less than 100 micrometers
iii) Micrite - remnant, 5%, patchy and intergranular
C. Stylolltes/Clay seams - very thin filled with dark residue, very abun't
microstylolites and few flat to jagged forms
D. Dolomitiaation - 50 -60 % fairly pervasive, 10-15 micrometers rhomb
size
E. Porosity - Minor moldic - filled, low to medium intercrystalline
F. Cement - minor less than 5%, coarse incomplete calcite void fill
G. Pore Fill - trace gypsum
78
Slide - A856
Depth - 574.19 m
A. Fossils - none visable
B. Allochems - i) Pellets - difficult to interpret due to dolomitization
ii) Spar- ID-30% all dolomite, cloudy core in some
with micrite rim
iii) Micrite - less than 5 %, intergranular
C. Stylolites/Clay Seams - nil
D. Dolomitization - 100% rhombs size 10 - 30 micrometers, well formed
interlocking
E. Porosity - minor moldic, high coarse intercrystalline to tight inter
locking porosity
F. Cement - absent or obscurred
G. Pore Fill - minor gysum
Slide - A858-5
Depth - 577.77 m
A Fossils - algal with some difficulty arising in separating vadose pis
olites from algal
B. Allochems i) Pellets - very few preserved in laminated seds
ii) Spar - less than 10 % very fine pseudospar
iii) Micrite - altered to spar
C. Stylolites/Clay seams - weak to absent
D. Dolomitization - 80 - 90 % , pervasive to patchy, less than 75 micro
meter rhomb size , poor to well formed
E. Porosity - low to moderate intercrystalline, with minor fenestral
F. Cement - absent or not preserved
G. Pore Fill - none
79
Slide - A859-4
Depth - 578.71 m
A. Fossils - some algal laminations
B. Allochems - i) Pellets - not well preserved
ii) Spar - 90- 95 % 50 -200 micrometers
iii) Micrite - remnant, less than 5%
C. Stylolites/Clay seams - a clay seam, 1mm thick filled with dark
residue and fine quartz-felspar? silt
stylolites are jagged
- less than 555 rhombs 50-100 micrometers as
fracture and vug fill
- low some intercrystalline in dolomitic areas
- some fibrous to drusy near clay seam, some coarse
calcite fill in pores
- trace gypsum
D. Dolomitization
E. Porosity
F. Cement
G. Pore Fill
Slide - A912-C
Depth - 580.77 m
A. Fossils - absent
B. Allochems - i) Pellets - none
ii) Spar- 95-10055 10-50 micrometers
iii) Micrite less than 3% at laminae and grain boundaries
C. Stylolites/Clay seams - absent
D. Dolomitization - 25 TL or less, rhomb size 50 micrometers, patchy
E. Porosity - weak intercrystalline, fenestra! (follows pisolite and algal)
F. Cement - absent
G. Pore Fill - less than 3% gysum
80
Slide - A860-6
Depth - 585.99 m
A. Fossils - pelecypoda fragments, algal laminations
B. Allochems - i) Pellets- patchy-poorly preserved
ii) Spar - 20-25%
iii) Micrite - less than 5Z remnant infills pellets
and shell fragments
C. Stylolites/Clay seams - very thin and jagged some microstylolites
D. Dolomitization - less than 25% patchy and weak, with rhomb size
generally less than 50 micrometers
E. Porosity - Moldic - minor filled with dolomite, vuggy filled
with radiating cement, and weak intercrystalline
F. Cement - 50 - 75 % fibrous ( radiating in vugs) minor radial, minor
coarse calcite
G. Pore fill - 5JK bladed anhydrite
Slide - A861
Depth - 588.72 m
A. Fossils - Algal laminations
B. Allochems - i) Pellets - weakly preserved ghosts
ii) Spar - pseudospar, 50 %, less than 50 micrometers
iii) Micrite - 5JK
C. Stylolites/Clay seams - barely visable-thin numerous jagged
D. Dolomitization - 50-60 3L patchy, no rhombs seen
E. Porosity - Low to nil, minor intercrystalline , minor vug
F. Cement - 50% minor coarse calcite with abundant fibrous calcite
G. Pore Fill - minor gysum and anhydrite (laths) in vug
81
Slide - A862-8
Depth - 590.07 m
A. Fossils - gastropods, algal filamentsB. Allochems - i) Pellets - dominant altered to spar in some cases
ii) Spar - 40% 10 micrometers
iii) Micrite - 50-60 % pervasive C. Stylolites/Clay seams - absent
D. Dolomitization nil
E. Porosity - low intercrystalline and low moldicF. Cement - less than 10 Z coarse crystalline vug fill, some fibrous G. Pore Fill - absent
Slide - A913-D
Depth - 595.58 m
A. Fossils - large pelecypoda, shells infilled with coarse radial and fib rous calcite, ostracodes and crinoid ossicles
B. Allochems - i) Pellets- relict
ii) Spar - 25-30% less than 50 micrometers
iii) Micrite - remantC. Stylolites/Clay seams - very thin and faint, a few jagged D. Dolomitization - nil
E. Porosity - minor moldic filled with anhydrite, minor vuggy, poor inter crystalline
F. Cement - 50 - 60 Z coarse calcite , abundant radial fibrous calcite G. Pore fill - trace anhydrite
82
Slide A 915-F
Depth - 597.41 m
A. Fossils - Shell fragments, crinoid ossicles, gastropods
B. Allochems - i) Pellets- relict and faint
ii) Spar - greater than 100 micrometers 99%
iii) Micrite - less than one percent
C. Stylolites/clay seams - weak and thin, jagged
D. Dolomitization - 40% patchy, no clear rhombs visable
E. Porosity - low porosity - poor intercrystalline
F. Cement - 35-40 % stromotactis filled with calcite cement (coarse)
mostly coarse sparry calcite, with fibrous in shells
G. Pore Fill - minor gypsum
Slide - A863-9
Depth - 598.20 m
A. Fossils - Algal, mollusks, brachiopods?, crinoids, ostracodes
B. Allochems - i) Pellets - abundant relict
ii) Spar - 100 micrometers, 90-95%
iii) Micrite - S-10% remnant associated with algal
C. Stylolites/Clay seams - weak thin
D. Dolomitization - nilE. Porosity - nil
F. Cement - 40%, coarse and fibrous calcite fills fossils
G. Pore Fill - trace bladed anhydrite
83
Slide - A914-F
Depth - 600.15 m
A. Fossils- abundant amphipora
B. Allochems- i) Pellets - abundant relict
ii) Spar - 100 micrometers, 99%
iii) Micrite - l% associated with algal
C. Stylolites/Clay Seams - very faint, fine whispy, horse-tail
D. Dolomitization - less than 2 % poorly formed rhombs, 10 micrometers
E. Porosity - nil, vug filled with coarse calcite
F. Cement - 40% fibrous in shell fossils, dogtooth in vugs
G. Pore Fill - less than 1JS anhydrite
Slide - A864-10
Depth - 601.29 m
A. Fossils - abundant crinoid ossicles, brachiopod/mollusk fragments
greater than 10% grains
B. Allochems - i) Pellets - abundant but relict
ii) Spar - 100 micrometers , 95-98%
iii) Micrite in shells less than 2 %
C. Stylolites/Clay seams - very weak to absent
D. Dolomitization - Nil
E. Porosity - Nil except infilled moldic
F. Cement - 30-40% fibrous calcite fill
G. Pore Fill - Nil
84
Slide - A865-11
Depth - 605.26 m
A. Fossils - abundant ostracodes, crinoid ossicles, algal
B. Allochems - i) Pellets - abundant but relict
ii) Spar - mosaic 50 - 100 micrometers, VO-95%
iii) Micrite - S-10% patchy assoc. with pellets,algal
C. Stylolites/Clay Seams - very thin, jagged weak and splayed
D. Dolomitization - 5% patchy, no well formed rhombs
E. Porosity - NIL
F. Cement - 40% radial fibrous calcite
G. Pore Fill - nil
Slide - A866
Depth - 609.22 m
A. Fossils - crinoid ossicles and arm plates, shell fragments, tabulate
coral fragments, ostracodes
B. Allochems - i) Pellets - abundant relict
ii) Spar - 10-50 micrometers, 955K
iii) Micrite - 5% pellet rims
C. Stylolites/Clay seams - very thin very weakly jagged but abundant
D. Dolomitization - SO-40%, 100-200 micrometer size rhombs or larger
patchy
E. Porosity - intercrystalline in dolomitic areas, intracrystalline in coral
fragments
F. Cements - lQ-20% coarse and fibrous calcite
G. Pore Fill - trace anhydrite laths
Slide - A921
Depth - 609.45 m.
A. Fossils - Amphipora, shell fragments, ostracodes
B. Allochems - i) Pellets - relict
ii) Spar - mosaic, 95Z
iii) Micrite -. remnant, 5%
C. Stylolites/clay seams - weak and thin very jagged
D. Dolomitization - 50% patchy, scattered 50-100 micrometer rhombs
E. Porosity - some vuggy, poor intercrystalline
F. Cement - SO-40% fibrous and coarse pore fill cement
G. Pore Fill r minor Halite
Slide - A920
Depth - 611.28 m.
A. Fossils - abundant crinoid ossicles, arm plates, ostracodes, bryazoans
B. Allochems - i) Pellets - weak but present
ii) Spar - mosaic - 50 -100 micrometer, 95%
iii) Micrite - 5% patchy
C. Stylolites/clay seams - numerous thin horsetail and jagged low
amplitude stylolites
D. Dolomitization - SO-60% Patchy, some 200 micrometer rhombs well
formed
E. Porosity - minor vuggy, coarse intercrystalline in dolomitized areas
F. Cement - 40% radiating fibrous calcite cement
G. Pore Fill - scattered trace anhydrite laths
86
Slide A916 - G
Depth - 611.43 m
A. Fossils - Bryazoans and tabulate coral fragments
B. Allochems - i) Pellets - absent
ii) Spar - mosaic coarse , 90-95%
iii) Micrite - remnant, S-10%
C. Stylolites/ Clay seams - nil
D. Dolomitization - 40-50 % patchy, some 50 micrometer laths in
calcite, 50 -300 micrometer size well formed
E. Porosity - mostly vuggy, partially filled, minor intercrystalline
F. Cement - 25-30% coarse fibrous calcite infill
G. Pore Fill - nil
Slide - A91? - H
Depth - 611.43 m
A. Fossils - large tabulate coral fragment, crinoid and bryazoans
B. Allochems - i) Pellets - nil
ii) Spar - mod - coarse mosaic, 90-95%
iii) Micrite - remnant ?? less than 10JE, Patchy in vugs
C. Stylolites/Clay Seams - very fine, thin horsetail or microstylolite
D. Dolomitization - 75-80% patchy - pervasive, 200-300 micrometer
well formed rhombs
E. Porosity - high intercrystalline porosity (due to plucking when
section cut???)
F. Cement - nil
G. Pore Fill - nil
87
Slide - A918-I
Depth - 611.86 m
A. Fossils - abundant crinoids
B. Allochems - i) Pellets -nil
ii) Spar - mosaic coarse crystalline, 95%
iii) Micrite less than 5% intergranular
C. S^ylolites/Clay seams - very fine h'orsetail, not abundant
D. Dolomitization - 25-3(^ very patchy, scattered rhombs well
formed 50-200 micrometers
E. Porosity - some vuggy, poor to moderate intercrystalline
F. Cement - less than 20JK, coarse and fibrous calcite
G. Pore Fill nil
Slide - A919-J
Depth - 611.89 m
A. Fossils - crinoids, large tabulate coral fragments
B. Allochems - i) Pellets - nil
ii) Spar - 90-95% mostly replaced by rhombs
iii) Micrite - less than 10%
C. Stylolites/Clay seams - nil
D. Dolomitization - 60-70 % patchy - pervasive, large rhombs 50-
200 micrometers
E. Porosity - some vuggy, mod to good intercrystalline
F. Cement - less than 20% coarse fibrous calcite
G. Pore Fill - nil
88
89
PLATE l THINS SECTIONS - DIFFERENT STYLOLITE TYPES - Fletcher Reef
The field of view in all of the photomicrographs in the next 3 plates
is approximately l cm.
A. TS 1197A 427.38 m., A-l Algal Stromatolite Unit, Consumers' 33408a
Typical flat stylolites of the argillaceous A-l Carbonate, Salina Fm.
The stylolites in this unit are difficult to discern from the algal(A)
stromatolites, but can be identified in thin section where they have
more of a concentration of insoluble residue and appear darker (st).
B. TS 3, 427.36 m. Eroded Reef Top /Lagoonal Facies,(stromatoporoid
floatstone), Guelph Fm., Consumers 1 33407
Transitional form of stylolite at the top of the Guelph Fm. Note the
jagged form (st) beginning to appear indicating that the amount of
argillaceous material is deminishing (Wanless,1984).
C. TS 10, 435.27 m., Reef Core Facies, Guelph Fm., Consumers' 33407
Jagged form of stylolite typical of the reef core facies of the
Fletcher Reef (st). This type of stylolite represents the argill
aceous poor end member of the classification by Wanless (1984).
Plate l
B
PLATE 2 THIN SECTIONS - AREAS WHERE CLAYS ARE CONCENTRATED
A. TS 911A 570.28 m., Bioturbated Algal Facies, Wilkesport Pinnacle
Some clay is found in the upper facies of the Wilkesport pinnacle
reef. This is tied up in the flat and anastomosing styldlites (st)
and in the matrix cements.
B. TS 913A 590.07 m., Pelletal Algal Facies, Wilkesport Pinnacle
Clays are also found further down in the reef, concentrated in stylol-
lites (st) as is shown here. The radiating crystals in this picture
are altered aragonitic marine cement.
C. TS 912A 580.77 m., Algal Stromatolite/Vadose Facies, Wilkesport
Pinnacle
The vadose silt seam and fracture fills of this facies appear to
contain small amounts of clays plus other detrital material (quartz?).
In some cases some of these fractures contain "dripstone" a cement
caused by subaerial exposure and dissolution of the carbonate.
92
f' Plate 2
B
93
PLATE 3 THIN SECTIONS - GREEN SHALE BED AT THE GUELPH FM. - A-l
CARBONATE CONTACT
A. TS 1201A 412.10 m., Consumers 1 33409 , Fletcher Reef
The green shale beds are often seen to merge with stylolites(M)
This is believed to represent a later stage diagenetic event.
B. TS 1201A 412.10 m., Consumers 33A09, Fletcher Reef
Thicker green shale bed showing relationship with stylolites as
described above.
c - TS 1393A 417.08 m., Consumers* 33408a, Fletcher Reef
Green shale bed showing some of the detrital material contained
within it (S). This could be wind bown silt and may represent a
period of subaerial exposure during which time the beds were
formed.
Plate 3
B
PLATE 4 CORE PHOTOGRAPHS OF THE FLETCHER REEF FACIES
1. A-l Carbonate-algal stromatolite, 415.68 m.,Consumers* 33407
Typical algal stromatolites (AL) found in the A-l Carbonate unit
of the Salina Fm.. The jagged form of the stylolites seen in this
core photo (st) is not typical of those found in this unit. They
are generally flat and difficult to discern from the algal material.
2. A-l Carbonate Pelletal Grainstone, 415.68 m.,Consumers' 33407
Typical pelletal grainstone of the A-l Carbonate unit, Salina Fm..
Pellets (P) in some cases appear graded. St is an example of the
most common stylolite form found in this unit.
3. Green Shale/Stylolite, 419.76 m.. Consumers' 33407
This subverticle green shale bed (GS) is bounded by a stylolite (st)
and is one of a series of beds which forms the contact between the
Guelph Fm. (below) and the A-l Carbonate (above). This bed is atypical
and may owe its origin to infill of cavernous porosity.
4. A-l Carbonate- Guelph Fm. Transitional Unit. 420.15 m.. Consumers* 33407
Bioturbated carbonate in the transition zone between true A-l Carbonate
rocks and the Guelph Fm.. The burrows (B) are seen as light,patchy
dolomite, which in some cases is seen to cut across previous sedimentary
features. Flat stylolites (st), typical of this unit, can also be seen.
96
Plate 4
97
PLATE 5 CORE PHOTOGRAPHS OF THE FLETCHER REEF FACIES
1. Lagoonal Facies (wackestone), Guelph Fm., 424.51 m.,Consumers'4000l
Large gastropod (G) in a dark brown dolomitized micrite (M).
2. Lagoonal Facies (wackestone), Guelph Fm., 425.28 m.,Consumers'4000l
Gastropods (G) and brachiopods (Br) in a dark brown dolomitized rnicr-*-
ite.
3. Lagoonal Facies (wackestone), Guelph Fm., 421.40 m.,Consumers'4000l
Possible marine cement (MG),as observed in the Wilkesport Reef,preser
ved in the upper part of the Lagoonal Facies, Guelph Fm..
4. Eroded Reef Top7Lagoonal Facies (stromatoporoid floatstone), Guelph
Fm., 431.29 m., Consumers* 40003.
Stromatoporoid fragments (s) are found with other reef-like debris.
The matrix of this debris is a dark brown, dolomitized micrite (H) .
Stylolites (st) in this unit are more jagged in form than those in the
overlying lagoonal facies.
98
Plate 5
99
PLATE 6 CORE PHOTOGRAPHS OF THE FLETCHER REEF FACIES
1. Eroded Reef Top/Lagoonal Facies (stromatoporoid floatstone), Guelph
Fm., 435.41 m.,Consumers' 33A07
Large stromatoporoid (s) fragments showing some evidence of erosion (E)
and partial dissolution and fracturing (F). '
2. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
431.40 m..^Consumers' 40001
Large tabulate coral (T) appears to be in growth position. Much of the
adjacent channel (Ch) and the intraparticle porosity in the coral is
infilled by white gypsum-anhydrite. Note also the gypsum-anhydrite
filled fractures (F) in the upper left of the photograph.
3. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
431.12 m.,Consumers 1 40001
Rugose solitary coral (r) in growth position
4. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
431.20 m., Consumers 1 40001.
Hemispherical stromatoporoid (s) in growth position. Note the vuggy
intraparticle porosity and jagged stylolites (st).
100
Plate 6
101
PLATE 7 CORE PHOTOGRAPHS OF THE FLETCHER REEF FACIES
1. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
445.12 m., Consumers' 33407
Large globular stromatoporoid (s) with minor rugose corals. Note the
jagged stylolite (st) at the top of the photograph. These are typical
of the form found in this unit.
2. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
444.00 m., Consumers* 33407
Reef coer debris consisting of cladopora (CI) corals and"Stromatoporoid
(s) fragments
3. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
435.50 m., Consumers* 40000
Heavily fractured (F) and vuggy (v) reef core rubble zone, with some
possible internal sediment (IS).
4. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
441.35 m., Consumers* 33407
Typical interframe-builder debris (in this case cladopora corals,CI)
giving the core a mottled appearance, which is diagnostic of this unit.
102
Plate 7
103
PLATE 8 CORE PHOTOGRAPHS OF THE FLETCHER REEF FACIES
1. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
441.15 m., Consumers* 33A07
Typical reef core debris (D) in between frame-builders,such as the
hemispherical stromatoporoid seen here (s). Note the vuggy porosity
(V) present throughout the facies.
2. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
432.98 m., Consumers* 33323
Internal sediment (IS) infilling some of the vuggy porosity (V) in
this sample (sample AOF).
3. Reef Core Facies (stromatoporoid-coral framestone), Guelph Fm.,
434.33 m., Consumers* A0001
Massive hemispherical stromatoporoid (s).
104
Plate 8
105
PLATE 9 CORE PHOTOGRAPHS OF THE WILKESPORT PINNACLE REEF FACIES
I.O.E Sombra 4-14-XIII
1. A-2 Anhydrite, Salina Fm., 556.87 m.
The A-2 Anhydrite consists of gyp sum-anhydrite (Gyp) and argillaceous
stringers (A) has what has been called a "chicken wire texture"
2. A-2 Anhydrite, Salina Fm., 557.33 m.
Large caliche? - Algal stromatolite beds disrupted by the growth
of gypsum-anhydrite (Gyp).
3. Fenestral Algal , A-l Carbonate, Salina Fm., 564.79 m.
Possible fenestral porosity (FEN) in dolomitized algal strom
atolite beds.
Plate 9
107
PLATE 10 CORE PHOTOGRAPHS OF THE WILKESPORT PINNACLE REEF FACIES
I.O.E Sombra 4-14-XIII
1. Algal-Vadose Facies, A-l Carbonate - Guelph Fm. f 557.75 m.
Typical vadose pisolite- caliche (P) of this facies. Note it is cut
by an infilled subverticle fracture and by a relatively flat stylolite
(st). Photo 3 in plate 2 contains a photomicrograph of this core piece
2. Algal-Vadose Facies, A-l Carbonate-Guelph Fm., 579.73 m.
Flat pebble conglomerate (F) indicating a disruption of the caliche-
algal bedding (C). This could represent an intertidal or tidal flat
environment.
3. Algal Stromatolite Facies, A-l Carbonate-Cuelph Fm., 577,49 m.
Typical encrusting and LLH type algal stromatolites (A) .
A. Algal-Vadose Facies, A-l Carbonate-Guelph Fm., 578.51 m.
Typical encrusting algal stromatolites (A) and jagged stylolites (st)
108
Plate 10
109
PLATE 11 CORE PHOTOGRAPHS OF THE WILKESPQRT PINNACLE REEF FACIES
I.O.E Sombra A-14-XIII
1. Pelletal Mgal Facies, A-l Carbonate-CueIph Fm., 588.26 m.
Dark brown algal mudstone with abundant marine cement (MG) giving
the core a mottled appearance
2. Amphipora Facies, Guelph Fm. 599.62 m.
Amphipora Sp. (A) stromatoporoids dominate two levels of this reef
3. Encrusting Stromatoporoid/Debris Facies, Guelph Fm., 619.81 m.
The only stromatoporoids found in this reef were tabular or encrusting
forms (Ts), contributing very little to the overall reef fauna. Note
the interframe-builder debris (D).
4. Tabulate Coral Facies, Guelph Fm., 623.93 m.
This Favosites Sp. (T) coral is the dominant tabulate coral found in
the reef. The intraparticle porosity is almost entirely plugged with
halite.
110
Plate H
PLATE 12 CORE PHOTOGRAPHS OF THE WILKESPORT PINNACLE REEF FACIES
I.Q.E Sombra 4-14-XIII
1. Coral Floatstone Facies, Guelph Fm., 614.48 m.
Tabulate coral fragments (T) in debris (D).
2. Grainstone (calcarenite) Facies, Guelph Fm., 627.28 m.
This is believed to represent the shoal on which the reef grew.
Very few fossils are visable, and it appears to be made up of
a dolomitized sand.
3. Basal Debris/Packestone Facies, Guelph Fm., 630.02 m.
Abundant brachiopod and crinoid debris make up this facies, which
is part of the biohermal stage of reef growth. Rugose corals (r)
and some vuggy porosity (v) can be seen in this photo.
112
Plate 12
113
PLATE 13 CORE PHOTOGRAPHS OF THE WILKESPORT PINNACLE REEF FACIES
I.O.E. Sombra 4-14-XIII
1. Contact Between The Guelph Fm. and the Goat Island Fm., 643.89 m.
The contact, marked by the white dashed line, separates the brachio
pod/ crinoid packestone facies of the Guelph Fm. (GU) from the more
argillaceous unit of the Goat Island Fm. (GI).
2. Goat Island Formation, 644.00 m.
Typical argillaceous (Ar), nodular, Goat Island Fm. with abundant cri
noidal debris (Cr).
114
Plate 13
115
Appendix C
APPENDIX C - REPRESENTATIVE CORE PHOTOGRAPHS
116
APPENDIX C REPRESENTATIVE PHOTOGRAPHS OF THE WILKESPORT
AND FLETCHER REEF DRILL CORES STUDIED
This appendix contains representative core photographs of each of the
major facies in both reefs. The black bar at the bottom of each plate
represents 2 cm. All core pieces are oriented with the top direction
to the top of the page.
117
Appendix D
APPENDIX D - DETAILS OF THE METHOD USED FOR REMOVALOF CARBONATE
118
APPENDIX D DETAILS OF METHOD USED FOR REMOVAL OF CARBONATE
Sample Preparation
1) Samples were cut from core using a water based cutting wheel
2) They were then cleaned to remove surface contamination using acetone
and distilled water, and then left to air dry.
3) The samples were crushed so that their size fraction ranged from 60
mesh to greater than 120 mesh. This was accomplished by stepwise
crushing and seiving. The crusher used was a shatterbox system,
which was run in 10 - 15 second bursts to limit possible dehydration
effects that friction heating may have on the clay assemblage. Although
the effects of the crushing technique are not precisely known to the
author it is assumed that the grain size fraction used in the acid
digestion process was coarse enough to limit any deleterious effects.
4) Samples were then solvent extracted using a soxhlet extractor. Chloro
form was used to remove the oils and bitumen, which could possibly
hinder the acid attack and cause problems with the x-ray diffraction.
Samples were extracted until the liquid was clear in the soxhlet tube
(approx. 4 hours).
Acid Digestion of Carbonate
1) Sodium acetate buffer solutions were made up to be mixed with the con
centrated acid. To obtain a buffer solution for a pH of 4.5 dissolve
205 g of sodium acetate in 2.5 liters of deionized water. Add either
acetic or hydrochloric*acid (the effect is essentially the same) until
the pH drops to 4.5. The pH of the stock solutions was tested using a
pH meter. Subsequent tests for pH during the digestion process were
conducted using pH paper.
* Hydrochloric acid dissociates in the buffer solution to form the equi
valent of a buffered acetic acid solution plus sodium chloride.
119
2) The samples were allowed to digest in this buffered acid solution for
up to 4 weeks before they were brought to neutral pH by washing with
deionized water. The majority of the carbonate (95Z or greater) had
been removed leaving an insoluble residue consisting of organics
(kerogen), sulphides, and clays. This was saved for the clay mounts.
It was found that the pH rose as the digestion process continued due
to the added buffering effect of the carbonate dissolution. To counter
this rise, drops of concentrated acid had to be added on a daily basis.
In addition to this, limestone samples being dissolved frequently allowed
for the precipitation of calcium acetate, a white crystalline solid.
This was prevented from occurring by changing the acid solution once
every three days. Dissolution of this precipitate can be accomplished
by washing the sample with deionized water.
Separation of Clay Size Fraction **
Two methods exist to separate the clay size fraction from the silt size
fraction. The first employs Stoke*s Law of settling. The second involves
the use of a centrifuge. Both methods require the sample to be dispersed
in a solution of sodium hexametaphosphate (50 g/liter), and sodium carb
onate (7 g/liter). For simplicity the latter method was chosen.
1) Samples were centrifuged at 600-700 RPM for 6 minutes to allow for the
clay-silt separation. The supernatent liquid containing the clay size
fraction (less than 2 micrometers) was then centrifuged to remove the
clays from suspension, and allowed to dry.
2) This clay size fraction (usually weighing between 15 and 80 mg) was then
divided and carefully weighed out on a Sartorius analytical balance. Two
sub-samples are required for the clay mounts.
3) One of the sub-samples was saturated with 10 ml of MgC^ (0.5 M), the
other with 10 ml of KC1 (1,0 M.). The samples were t sr centrifuged
and washed with deionized water to remove excess salts. Wash at least
two times. This saturation process is done as a treatment to aid in
the clay mineral identification process.
4) Each of the treated sub-samples was then pipetted onto a glass slide
and allowed to air dry. This creates an oriented clay mount on which
120
to conduct qualitative x-ray diffraction work.
** This method is that used in the Soil Science Department at the
University of Guelph. It is outlined in more detail in a handout
provided to the author by Mr. Glen Wilson.
121
Appendix E
APPENDIX E - SELECTION AND TESTING OF THE CLAY SEPARATION TECHNIQUE USED
22
1. APPENDIX E SELECTION AND TESTING OF THE CLAY SEPARATION TECHNIQUE USED
1.1 Problems With The Selection of an Extraction Method
To meet the objectives of the thesis an extraction method had to be selected
that would allow for the rapid dissolution of both limestone and dolomite without
damaging the clays. Unfortunately, many chemical extraction methods either take
considerable amounts of time to complete, or they dissolve the clays. The selec
tion of a technique had to take into account these factors.
Ostrom (1961) outlined the factors effecting the dissolution of clay minerals in
general. These included the nature of the acid used, its concentration, the acid-to-
clay ratio, temperature, duration of treatment particle size, relative solubility, and
clay mineral crystallinity. These points are valid but the effect of structural varia
tions within and between clay families may exert more of a control on the solubili
ties or reactivity of various clays in various acids.
It is well known that each clay mineral family reacts differently to acid treat
ments, based on differences in their structure (Ray et al., 1957; Nutting, 1941). For
example the smectite family of clay minerals is more soluble in acid than any oth
er group (Ray et al., 1957;Nutting, 1941). Likewise iron chlorites are also susceptible
to acid attack (Ross, 1969). On the other hand members of the kaolinite and illite
families are relatively insoluble in dilute acids. The low solubility of illite in the
acid used in this study is a good example of its behavior. Almon and Davies (1981)
noted that kaolinites were extremely insoluble in acids compared to other groups
of clay minerals.
Variances in relative acid solubility exist between members of the same clay
mineral family, which may be partially due to crystallinity, but are more likely due
to differences in composition and structure (Jackson et al., 1952). Dioctahedral
clays are likely to be affected to a lesser degree than trioctahedral clays of the
same family when subjected to acid treatments (Jackson et al., 1952). The evi-
123
dence for this hypothesis lies in the observation of the natural weathering pro
cesses involving clays. This represents a slow reaction rate analogy of the acid
digestion process, involving weaker acids.
An example of this involves observations made on the weathering of biotite
(trioctahedral) and illite (usually dioctahedral), by Jackson et al. (1952). They ob
served that biotite usually weathers to illite, which then weathers to kaolinite and
finally to gibbsite as the dissolution and cation stripping process continues.
A method proposed by Rabenhorst and Wilding (1984) was chosen for use in
the study, even though it was believed at first that it had to be modified and
thoroughly tested to be reasonably sure that acid sensitive clays were not being
significantly damaged or removed.
Initial modifications to the method involved the substitution of HCI for acetic
acid in the buffered solution. However, the assumption that the HCI created an
improvement on the acetic acid buffer solution was later proved to be invalid. The
HCI simply dissociated to acetic acid and sodium chloride in the presence of the
acetate buffer making the solution no more effective than that of the one proposed
by Rabenhorst and Wilding (1984). On this basis the method used can be said to
be that of Rabenhorst and Wilding (1984).
Unfortunately, this was not discovered until late in the thesis, after the x-ray
diffraction work had been completed. Nevertheless a clay mineral fraction was
successfully removed from the samples for the analyses.
The only modifications made on the method proposed by Rabenhorst and
Wilding (1984) were essentially the use of agitation and a reduction in the sample
size. This appeared to cause a marked improvement in the dissolution rate of the
dolomite.
184
1.2 Testing of the Method Used
Testing of the Rabenhorst and Wilding (1984) method was conducted to deter
mine, on a preliminary basis, if biasing was occurring due to the removal of one or
more clay mineral phases by the acid treatment. Possible biasing in the results
was suspected when illite was the only clay mineral found in the samples from the
two Silurian reservoirs. Previous studies had indicated that samples from similar
reefs, and from the shales above and below the reefs in southwestern Ontario
contain small amount of kaolinite and chlorite in addition to the illite (Egbogah and
King, 1985; Guillet, 1977; Miles et al., 1985).
Various clay samples were obtained from the University of Guelph to be used
in the experiment. These consisted predominantly of trioctahedral members from
the smectite (hectorite) and chlorite (Fe rich chlorite) families. Testing was also
conducted on various other clays all of which are listed in table 1.
Hectorite is a trioctahedral, lithium rich member of the smectite family, which
has been shown in previous studies to be the most acid sensitive of all of the
smectites (Ostrom, 1961;Nutting, 1941). The hectorite chosen for use in the experi
ment was Hectorite #34, from Hector, California.
Various treatments were conducted. Two samples of powdered hectorite
weighing 50 mg each were added directly to the buffered acid solution. A 2 mi
crometer size separation was plausible due to the swelling properties inherant in
this clay. Two other samples, also weighing 50 mg, were mixed with 5 grams of
dolomite from the Fletcher field and then subjected to the acid treatment. These
treatments were conducted to determine two things. Firstly, the experiment was
designed to delineate what effect, if any, the dolomite might have on prevention of
clay dissolution. Secondly, by making up simulated one weight percent samples it
was hoped that a lower detection limit for the acid digestion method could be de
termined.
125
TABLE l List of Clay Samples Used In The Acid Digestion
Experiment
Sample Location
Chlorite Unknown
Prochlorite Chester,
Vermont
Whole Rock
Geochemistry
Aqueous XRD Traces
Geochemistry
none none A,C**
Fe, Mg,K,Ca,Al Fe,Mg,K,Ca, B,C
Al,Si
Haldimand TillChlorite- illite
Nanticoke,
Ontario
none none E,F,G
Hectorite Hector,
*34 Calf.
Rectorite unknown #3
Fe,Mg,K,Ca
Al,Li
none
Fe,Mg,K,Ca, A,B,C,D
Al,Si,Li
none A,B,C**
Montmoril- Upton,Ionite #25 TTWyoming
none none A,B,C
*A - dolomite plus sample, treated with acid
B - sample treated with acid alone
C - sample not treated with acid - control
D - sample glycol solvated
E - Haldimand Chlorite physical separate, not treated with acid
F - Haldimand Chlorite physical separate, treated with acid
G - Haldimand Till, Bulk sample treated with acid
** X-ray diffraction traces found in the rear of this appendix along
with glycol solvated traces from hectorite # 34.
126
Ross (1969) demonstrated that iron rich chlorites dissolve more readily in acid
than magnesium rich varieties, therefore, two iron rich chlorites were used in this
experiment. The first consisted of a prochlorite sample, which has been previously
identified as being trioctahedral (Carroll, 1970). A sample of the less than 2 mi
crometer fraction of this sample was mounted on a glass slide and an x-ray dif
fraction trace was obtained to ensure that the clay was in fact iron rich. The rela
tive ratio of the 7 and 14 angstrom peaks were used to determine this after a
method described by Brindley and Brown (1980). The prochlorite proved to be iron
rich because the intensity of the 7 angstrom peak was greater than that of the 14.
This observation was confirmed by the results of whole rock geochemistry con
ducted on this sample. (The results of these analyses and those of the other clay
samples can be found in table 2 in the next section.)
The second chlorite sample used was extracted from the Haldimand Till of
southern Ontario. This sample (1-5) was supplied to the writer by Mr. Andre Vo-
rauer, a graduate student at the University of Waterloo. The presence of iron rich
chlorite in the sample was determined by x-ray diffraction alone, for whole rock
geochemical analyses could not be performed on this sample due to the presence
of other minerals and contaminants in the less than 2 micrometer fraction. Mr. Vo-
rauer conducted heat treatments on a physical separate of this till using a method
outlined by Quigley et al.(1973) and determined the clay mineralogy to consist of
illite and iron rich chlorite. This sample was chosen over others because it was
believed to possibly contain a similar chlorite to that found in the Silurian rocks
being studied. Both bulk and and less than 2 micrometer fraction samples were
used in the experiment. The effect of weathering on this clay was not taken into
account in this study. This sample may have been altered due to weathering be
cause it was collected from a near surface location.
127
The samples and sample-dolomite mixes were placed in an buffered acid solu
tion for a period of 20 days. They were stirred daily and the pH was checked and
adjusted once every three days using a calibrated pH meter
Supernatent solutions of all the samples except the Haldimand Till were col
lected and analyzed for Fe, Mg, Al, Si, K, and Li. The results are compiled in table 3
in the next section. These values were compared with those obtained from the
whole rock geochemical analysis of the samples themselves and a measure of the
degree of dissolution was calculated in terms of each major element. (The whole
rock geochemical data was obtained from digesting the samples using a method
modified after that of Pruden and King, 1969, and then analysing the liquids using
atomic absorbtion.) A similar experiment had been conducted earlier but samples
of the supernatent liquid at the end of the digestion process were not collected for
analysis. These samples of hectorite were subjected only to x-ray diffraction anal
ysis.
1.3 Results of Testing of the Method Used
The results of the geochemical study can be found in tables 1, 2, 3 and 3B,
and 4. Table 1 consists of a list of the samples used in the study and table 2
containsthe whole rock analysis of these samples. Table 3 and 36 contain the
geochemical data derived from the supernatent liquids obtained from the acid di
gestion experiment, and table 4 summarises the calculations made with regard to
the degree of dissolution of the clay in terms of major elements. This was done
by comparing the amount of any given element in the supernatent liquid with the
original amount of the element in the clay sample.
The entire experimental procedure used to obtain this geochemical data had
an indeterminant amount of error. Calculation of the precision involved in the
128
TABLE 2 Whole Rock Geochemical Data - Clay Samples Used
Sample K20 Fe203* Fe0* Ca0 MS0 A1203 Si02 Li20
Hectorite 0.04 , 0.03 20.51 10.45 *C0.45 ——— 0.48 34-1
Hectorite 0.05 0.08 17.87 12.03 < 0.45 ——— 0.54 34-2
Hectorite 0.06 0.09 16.64 16.47 < 0.47 ——— 0.85 34-3
Hectorite 0.09 0.06 17.74 16.32 0.99 ——— 0.83 34-4
Average - 0.06 0.07 18.19 13.82 ^.47 ——— 0.68 Hectorite
Additional Hectorite analyses from the literature (Grim, 1968;Weaver, 1973)
Hectorite 0.23 0.03 0.16 25.89 0.14 53.95 1.22 Hector, Calf . (Grim, 1968)
Hectorite 0.08 0.12 0.90 24.51 0.33 55.17 1.44 Hector, Calf . (Weaver, l 973)
Prochlor- 0.01 7.64 0.02 10.31 7.48 ——— ——— ite-1
Prochlor- 0.02 13.36 0.43 18.02 13.07 ——— ——— ite - 2
Average OB Io755 5723 TOT lOl ^^ IZI:::Prochlor ite S
Additional analysis from the literature (Grim, 1968)
Prochlor- ——— 26.52 3.32 17.60 21.26 23.69 ite
* Iron species not identified during analysis (ie: is total Fe)129
TABLE 3 Corrected Major Element Concentrations In Supernatent Liquid From the Acid Digestion Experiment
Sample K O Fe^* FeO* CaO MgO Al^ Si02 Li O
Hectorite 0.04 ** 18.65 8.64 <0.14 15.67 0.24 34-1
Hectorite 0.04 ** 18.32 7.10 ^.14 13.54 0.2134-2_________________^______________________Average 0.04 18.49 7.87 -C 0.14 14.61 0.225
Hectorite ** ** 14.20 nil -C0.56 1.80 ^0.02 S dolomite -l Hectorite Sdolomite - 2__ . ._________**_____14.20 nil * 0.54 1.53 ^.02Avera8e 14.20 n/a -C 0.55 1.67 ^; 02
Prochlor- 0.06 0.53 0.10 1.41 0.84 1.48 ite - l
Prochlor- 0.06 0.53 0.31 1.66 0.81 1.63 ite - 2^-—^^—^^——-——-——-———————————,——Average 0.06 0.53 0.21 1.54 0.825 1.56
The values used to make the corrections on this data are contained in table 3B. See sample calculation in table 3B.
* Iron species not identified during analysis (ie: is total Fe)** Too small to determine accurately given the magnitude of the
corrections required and the fact that operator working close to detection limit.
130
TABLE 3B Corrections For Aqueous Geochemical Data In Table 3
The raw data obtained from the atomic absorbtion unit had to be corrected for the existance of various elements in the stock solutions and in the dolomite used to make up one weight percent clay samples. It is these corrections which introduce considerable error into the calculations making some of the data unusable. In some cases the stock and dolomite values for a specific element were in excess of the amount found in the sample solutions. This could be a dilution error. In other cases when working with very low numbers, close to the detection limit errors of this sort are more likely to occur. This data is expressed in mg/liter and the correction was applied to each element in table 3 before conversion to wt.% oxide.
Correction
Dolomite-1
Dolomite-2
Average
Dolomite
K
0.
0.
0.
014
008
012
Fe
0.
0.
0.
total
03
03
03
Ga
29
29
29
.44
.07
.26
Mg
21.
21.
21.
Al
28
08
18
Si
Na Acetate 0.257 0.25 ^.05 0.01 ^.04 1.2 Stock Buffer
eg. raw geochemical data (ppm) - average dolomite value (for each element)
Na acetate stock value (for each element) ~ corrected value listed in
table 3 when converted to percent oxide.
This correction was applied to the samples mixed with dolomite only.
Other samples were just corrected using the Na acetate stock numbers
in ppm, then they were converted to percent oxide to equal the values
found in table 3).
131
TABLE 4 Calculated Dissolution of the Clay Samples From The Acid Digestion Experiment Expressed as a Percentage
Sample K20 Fe203* Fe0 Ca0 Mg0 A1203 Si02 Li 20
Hectorite 66.70 0.00 100.00 62.52 ** 28.72 35.55 34-1
Hectorite 66.70 0.00 100.00 51.37 ** 24.82 31.11 34-2
Hectorite ** ** *** 0.00 ** 3.29 2.96ft dolomite-1
Hectorite ** ** ** 0.00 ** 2.80 2.96S dolomite-2
Prochlorite ** 5.04 43.10 9.95 8.17 6.25 ———1
Prochlorite** 5.04 ** 11.71 7.87 6.88———2
* Iron species not differentiated during analysis (ie: is total iron)** Too small to determine accurately given the magnitude of the corrections
required and the fact that the operator was working close to the detect ion limit of the instrument.
Values calculated using the following formula:
Wt% oxide from table 3oxide from table 2 X 100 * "Z, dissolution
18
method used are to be found in Tables 2 and 3 along with the data. This error in
stated as the standard deviation of the mean. The error was great enough in
some cases to make the final summary calculations in table 4 unusable, however,
general trends in the data can be seen.
The calculations in table 4, representing the percent dissolution in terms of in
dividual major elements, show that although dissolution of the acid sensitive clays
did occur this was mainly confined to samples which were placed directly into the
buffered acid bath. The hectorite sample mixed in with dolomite showed less than
5 percent dissolution in terms of the major elements analyzed.
X-ray diffraction traces of the acid sensitive clays used in the main part of the
experiment can be found in figures 1 to 4. Traces of the other clays tested in pre
vious experimentation may be found in the rear of this appendix.
The x-ray diffraction traces of all of the clay samples used in the experiment
appear to indicate that no significant damage to the clay structure occurred which
would render the identification of the clay minerals impossible, however, crystallin
ity of the clay samples chosen may differ from those found in the reservoir rocks
being studied. It is beyond the scope of this thesis to delineate this further.
Traces of samples made up to one weight percent clay by the addition of reservoir
dolomite show no significant difference from those of the control not subjected to
the acid treatment.
X-ray diffraction analysis of a the less than 2 micrometer fraction, physically
separated from the vadose silt of the Fletcher reef does not indicate the presence
of any clay minerals other than illite in the reef. (See figure 5.) This supports the
hypothesis that biasing did not occur during acid digestion of the carbonates.
133
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Appendix F
APPENDIX F - SCANNING ELECTRON MICROSCOPE AND KEVEXEDS ANALYSIS DATA
146
APPENDIX F SCANNING ELECTRON MICROSCOPE AND KEVEX EDS
DATA
The scanning electron microscope, coupled with a KEVEX EDS analyzer
can be used to locate and tentatively identify clay minerals and other
fines in reservoir materials. It can also be used to study intergranular
porosity/permeability relationships, diagenetic materials, and pore
geometry.
Interpretation of the possible clay mineral assemblage is accomplished
using the observed form and habit of the particles as seen on the SEM, by
utilizing the particles location in relation to other grains and constit
uents (eg. in the pore space, matrix etc.), and by the crude elemental
analysis provided by the KEVEX. (The data obtained from the latter system
can only be used qualitatively in light of the sample preparation technique
used.)
This appendix contains representative SEM photomicrographs, which are
discussed in the main body of the thesis. The remainder of the SEM photo
micrographs can be found on file in the Earth Sciences Department. All the
KEVEX traces obtained during the course of the study are also included in
this appendix.
The KEVEX analyses were conducted on specific particles noted during the
SEM study,which could have been clays. The beam was focused on the particle
by increasing the magnification sometimes in excess of 40,000 x, thus limit
ing deleterious effects which may caused by adjacent p'articles. Where no
apparent clay particles were noted, or where there was little or no visable
porosity, the matrix was analysed to determine if clays were present.
47
The elements found on the KEVEX traces may be assigned to various mineral
families or species.
- Ga and Mg are associated with the dolomite and limestone
- Fe and S with sulphides
- Ga and S with sulphates
- Au with the conductive gold coating
- Al, Si, and K with the clay mineral illite or muscovite
It is the latter set of elements that is chiefly of interest in this study.
SEM photomicrographs contained in this appendix were acquired to show rep
resentative features of the sample and are not taken at the same magnification
as the KEVEX analysis was conducted. The area analyzed in each,therefore,may
be interpreted as being roughly the center of the photograph.
Each SEM photomicrograph is labelled as follows:
2002 25KV x2300 10 urn WD 39
Sample accelerating magnification scale working distance ID voltage bar from final lens
For purposes of identification the user is generally only concerned with
the magnification, scale bar, and sample identity.
148
Appendix F Samples For SEM/KEVEX Analyses
Sample ID Field/Well
1W2W3W4W5W6W7W8W9W10WHW12W13W14W15W16W17W1SW19W20W21W22W
Wilkesport 560,07564.87569,09569.62571.45575.54578.82582.32584.94590.70597.41608.56607.97611.84615.19619.66623.93626.08629.41629.97633.98644.96
Facies
Anhydrite Algal Bioturbated Algal
Algal/Vadose
Pelletal/Algal tt n
Algal Boundstone Crinoidal Algal Algal Boundstone Coral Floatstone Tabular Stromatoporoid Coral Framestone Basal Debris Calcarenite/Grainstone Basal Reef Debris Contact Goat Island Goat Island Formation
149
Samples For SEM/KEVEX Con't
Sample ID Field/Well
23F Fletcher 24F 33407
25F26F27F28F29 F30FSIF32F33F34F35F36F37F Fletcher 38F 40003
39 F40F Fletcher
33323
41F Fletcher 42F 40001
43F
Depth
415.33 418.62419.59420.28421.00425.72427.53431.55434.39435.06436.13438.29442.00444.39427.58 431.29436.57432.98
424.51 429.72432.28
Facies
A-l Carbonate H H
Guelph-A-1 Contact ? Bioturbated Guelph? "Green Shale" Eroded Reef Top
Reef Core (strom.-coral M framestone)
Eroded Reef TopM II
Reef Core (strom.-coral Vadose Silt? framestone)
Eroded Reef Top
Reef Core (strom.-coral framestone)
150
Samples for SEK/KEVEX Con'tSample
40-8823-1723-1801-4801-5001-5101-5501-6201-6601-7101-7201-8101-8501-8801-9501-10401-11201-11607-143
ID Field/Well
Fletcher 40000Fletcher 33323
II M
Fletcher 40001
Fletcher 33407
Depth (m)
434.50432.20432.68419.77420.13420.50421.88424.38425.28426.74427.11429.08429.99430.72432.28435.08437.42438.11444.55
Facies
Reef core( Strom^coral " " framestone)II M
Guelph Lagoonal/ (wackestone)
Eroded reef toP/ lagoonal
Reef core (strom.-coral M framestone)
For additional samples please see Meadows (1986). A B.Se. thesis on the Fletcher Patch/Barrier Reef Complex.
151
PLATE 14 SEM PHOTOMICROGRAPHS OF NON-POROUS DOLOMITES IN THEFLETCHER REEF
This plate consists of photomicrographs showing various samples with little
to no porosity. Extreme dolomitization has effectively removed any primary
porosity. Clays that were detected in the KEVEX and X-ray Diffraction
studies are believed to be hosted in the dolomite cement and are not likely
to come into contact with fluids introduced into the reservoir.
A. Sample 30F Consumers 1 33407, Eroded Reef Top/Lagoon (stromatoporoid
floatstone)Facies
Non-porous dolomite with no visable or detectable clays. Dolomite rhombs
interlock and occlude porosity.
B. Sample 31F, Consumers 1 33407, Eroded Reef Top/Lagoon (stromatoporoid
floatstone)Facies Interlocking dolomites with little or no clay (none
visable).
C. Sample 34F, Consumers f 33407, Reef Core (stromatoporoid-coral framestone)
Facies Typical non-porous dolomite of the reef core facies, no clays.
D. Sample 23-17, Consumers* 33323, Reef Core (stromatoporoid-coral
framestome) Facies non-porous dolomite, no clays detectable.
152
Plate 14
PLATE 15 SEM PHOTOMICROGRAPHS OF POROUS-CLAY-FREE DOLOMITES IN THE FLETCHER
REEF
This plate contains representative SEM photomicrographs of some of the more
porous zones in the samples from the Fletcher Reef. No clays were detected
in any of the samples shown below.
A. Sample 3IF,Consumers* 33407, Eroded Reef Top (stromatoporoid floatstone)
Facies Note one of many tetragonal pores (p) in this photo.
B. Sample 01-88, Consumers 1 40001, Eroded Reef Top (stromatoporoid floatstone)
Facies Tetragonal pores indicated by (p) are clay free.
C. Sample 23-17, Consumers* 33407, Reef Core (stromatoporoid-coral frame
stone) Facies Sample shows clean pores and the relationship between
pore-filling gypsum (G) and the dolomite (D).
D. Sample 34F, Consumers 1 A0001, Eroded Reef Top (stromatoporoid float
stone) Facies Abundant tetragonal pores in this sample (p) all of which
are clay free.
164
Plate 15
til
PLATE 16 SEM PHOTOMICROGRAPHS OF THE GREEN SHALE AND "VADOSE SILTS" OF
THE FLETCHER REEF
This plate contains representative SEM photomicrographs of some of the more
argillaceous/clay-rich units in the cores studied. The clay mineral present
in each of these photos is illite (as confirmed by x-ray diffraction and chem
ical analysis). Typical KEVEX traces for these type of samples can be seen in
plates 21 and 22.
A. Sample APF, Consumers 33323, Reef Core (stromatoporoid-coral framestone)
Facies "Vadose silt" from reef core.
B. Same as above
C. Sample 27F, Consumers* 33407, Green Shale Bed, Contact Between Guelph Fm.
and the A-l Carbonate of the Salina Fm. Abundant granular illite makes up
the majority of this sample
D. Sample Fletcher-1, Consumers' 33408a, Green Shale Bed, Guelph-A-1 Contact
Green shale bed made up of primarily illite and some other detrital material
which includes quartz. Note the residual dolomite rhomb (D) in this sample.
156
Plate 16
157
PLATE 17 SEM PHOTOMICROGRAPHS OF SAMPLES CONTAINING ABUNDANT CLAYS
WILKESPORT AND FLETCHER REEFS
This plate contains representative photomicrographs of occurrances of clays
in both reefs. Photos B and C (sample HW) represent the only time that clays
(illite) were found in the pore space. This occurrance may be associated with
a stylolite.
A. Sample 01-51, Consumers' 40001. Green Shale Bed Top of Guelph Fm.
Similar to that show in the previous plate. Clays consist of Illite.
B. Sample HW, Wilkesport Pinnacle Reef, I.O.E Sombra 4-14-XIII, Pelletal/
Algal Unit Abundant illite (I) as confirmed by KEVEX and X-ray Diffrac
tion work, is seen in the pore space between dolomite rhombs (D). The
habit although not clearly seen in this photo is granular.
C. Same as Above but at higher magnification
D. Sample Fletcher-8, Consumers 1 33A08a, Green Shale Bed, Top of Guelph
Fm. Green shale bed similar to that described in the previous plate.
158
Plate 17
159
PLATE 18 SEM PHOTOMICROGRAPHS OF THE A-l CARBONATE OF THE FLETCHER REEF AND
THE LIMESTONES OF THE WILKESPORT REEF- POROUS CARBONATE WITH NO
VISABLE CLAYS
This plate contains representative SEM photomicrographs of a sample from the
A-1 Carbonate of the Salina Formation and of samples of the limestone from
the Wilkesport Pinnacle Reef. No clays were noted in the pore space of any of
these samples.
A. Sample 23F, Consumers* 33407, A-1 Carbonate of the Salina Formation
Clay free pore space amoungst interlocking dolomite rhombs (D).
B. Sample 9W, Wilkesport Pinnacle Reef, I.O.E. Sombra 4-14-XIII, Algal/
Vadose Facies Pinpoint porosity in this facies is clay-free.
C. Sample 3W, Wilkesport Pinnacle Reef, Bioturbated Algal Facies
Clay-free pore space (p) in limestone of the Wilkesport Reef
D. Sample 7W, Wilkesport Pinnacle Reef, I.O.E Sombra 4-14-XIII, Algal/
Vadose Facies Small Vug appears clay free (V), surrounded by dogtooth
sparry calcite.
Plate 18
161
PLATE 19 SEM PHOTOMICROGRAPHS OF CLAY FREE PORE SPACE IN LIMESTONES OF
THE WILKESPORT PINNACLE REEF - I.O.E. Sombra 4-14-XIII
This plate contains photomicrographs of representative porous limestone
samples from the Wilkesport Pinnacle Reef. No clays were detected in these
samples.
A. Sample l5W, Coral Floatstone Facies
Abundant fine intergranular porosity with no visable clay mineralization.
B. Sample HW, Pelletal/Algal Facies
More of the typical limestone intergranular porosity with no detectable
clay fill.
C. Sample 3W, Bioturbated/Algal Facies
Porosity created by coarse dogtooth calcite (p) contained no detectable
clays. The radiating crystals to the left of the photo are recrystallized
aragonite cement.
D. Sample 21, Contactof the Guelph Fm. with the Goat Island Fm.
This moderately porous sample (pores indicated by p) contains no visable
clay mineralization.
Plate 19
PLATE 20 SEM PHOTOMICROGRAPHS OF CLAY-FREE PORE SPACE IN DOLOMITES FROM
THE WILKESPORT PINNACLE REEF - I.O.E. Sombra A-14-XIII
This plate contains photomicrographs of representative porous dolomites from
the Wilkesport Pinnacle Reef. Dolomitization of this kind creates the reserv
oir in this reef at the top and at the bottom. There was no detectable clays
in the pore space of these samples.
A. Sample 22W, Goat Island Formation
Nice intergranular porosity but no clays
B. Sample 9W,Algal/Vadose Facies
Clay free intergranular porosity (P) in coarsely dolomitized section of
this upper reef facies.
C. Sample 16W, Tabular Stromatoporoid Facies
Interlocking dolomites restrict porosity further (P). No clay minerals.
D. Sample HW, Pelletal/Algal Facies
Nice intergranular porosity (p) free of clay minerals.
164
165
PLATE 21 SEM AND KEVEX TRACE FOR SAMPLE 40F FROM THE FLETCHER REEF -
"VADOSE SILT"
The KEVEX trace and accompanying SEM photomicrograph indicate that this samp
le contains illite in its clay mineral assemblage. This is interpreted from
the relative peak ratios of the Al, Si, and K on the KEVEX and from the gran
ular form of the clay. The findings of the KEVEX and SEM results presented
here were confirmed by x-ray diffraction and by chemical analysis for K.
Plate 21
(T)
a w
•-l i O :CL:h-
W ::::•P ::::C ::::3 ::i:O ::::o j;i:
S) li i!CD ::::O ::::in : —
U
m
Lm(b
OmOJ
C3
iiQj O)c
sOJCO
•b
1C?
PLATE 22 SEM AND KEVEX TRACE FOR SAMPLE 27F FROM THE FLETCHER REEF -
GREEN SHALE BED AT THE TOP OF THE GUELPH FORMATION
The KEVEX trace and accompanying SEM photomicrograph shows the presence of
abundant detrital illite (I). This was interpreted again from the Al,Si, and
K peak ratios on the KEVEX and by the granular habit as observed on the SEM.
The findings of these studies were substantiated with X-ray Diffraction. The
presence of iron in this sample may be due to sulphides in this shale bed. The
Ga and Mg is associated with the dolomite.
168
Plate 22
CD TTa*-
CD ^t•a*
in
inCOen
T3 r — .V.":?.K
O O
CS) :-:|iQ J--, i(s ;coOJ :::r
: 3 :CC
Ei (Ti CO
CD.E)
*
o
I'M
169
PLATE 23 SEM AND KEVEX TRACE FOR SAMPLE FLETCHER-6 FROM THE FLETCHER REEF-
GREEN SHALE BED AT THE TOP OF THE GUELPH FORMATION.
The KEVEX trace and accompanying SEM photomicrograph shows the presence of
abundant illite in the green shale beds which mark the contact between the
Guelph Fm. and the A-l Carbonate of the Salina Fm.. The presence of the clay
mineral illite is indicated by the relative ration between the Al,Si, and K
peaks and by the granular form. The findings of this study were confirmed by
X-ray diffraction. Note the large residual dolomite rhomb, commonly found in
the shales of this unit (D). The illite (I) in some cases is smeared around
these rhombs.
170
Plate 23
•l'
n
; l
^!!:i:V s^ *
171
PLATE 24 SEM AND KEVEX TRACE FOR SAMPLE FLETCHER - 5 FROM THE FLETCHER REEF -
ILLITE IN THE PORE SPACE
This KEVEX~trace and its accompanying SEM photomicrograph shows the presence of
abundant detrital illite (I) situated in the pore space between dolomite rhombs
(D). The presence of illite is interpreted from the Al, Si, and K peak ratios,
by its form and habit, and by the x-ray diffraction results conducted on simil
ar samples. Illite being present in the pore space does pose some difficulty for
oil recovery, however, cases such as the one seen here are rare in the reservoir
studied. It was found that the majority of the pore space is virtually clay-free.
172
Plate 24
* * * .j*- * . V . . * . , .,~. . 4***' i.. W* r *.V *. j V*:*.^,. * ,- .,*:*,4F-*-^*-. P* .-tr* ** t.*..*.*-*i.i..--..^*fc..--*V*v-v*r'i-*-' ;
. .-* ... . ^. .. ... . . .**.^o...tt
..w* . .-.. . .. . .. ...,. ,,..,'.
173
6-Nov-1985 14:24:47
Vert= 10008 counts
!;iii;iii:'ii:ii.: :i;:.: .: i;if:'iiii::;;ii;i;i;ii;;;ii!i;ic
................................. . . . . . . . . . . . . . . . . . . .u
'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.".'.'.l'.'.'.'.' " " ".' "."" ' " " " ".' "*
::::::::::::::::::::::::-:flij:::::::::::::::::::i -:^:^:::ftpl*^|\S^^
4- 0.320 Range =
4^4P^eset= 100 sees
Disp= 1 Elapsed= 100 sees
,a::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:::::;:i:;:;::;i:::::::::SfiMPLEi : :lW:: ::: ii;:::::-^:: : -":""":""::":::":"""::"::"
::::::::::::::::::::::::: PHOTOS:::! 001 -2 ;:::::i::i:iiii":iiiiiliiiiili:'liiii'::::l::i:i:i
i........................................................................................................
vCa :::::::::::::::::::::::::::::::::::::::-:::::::.::::::.:::;::::::::::::;::::::::::: : ::-::::::::: : .-V:::::::::::::::::::::::::;:::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::::::::::::::a i...................................................................................................
^;;:;;::;;:;::;::;;::::;;:::^L:;^^^I:^10.230 keV 10.230 -f
Integral 0 z 250369
6-Nov-l
,/ert =
i; ii f
9
1
iu S i
85 14:*
0000 cc
i pi i!:| ^h—
10:46
)unts Disp= 1
Car
km
-C*/;
' ,4 '^-KT* 'in.. M. ...M
P r e s e t s E 1 apsed *
SAMPLE a- i PHOTOS Z001-C
100 sees 100 sees
-iftiV..M4- 0.480 Ra.nge= 19.230 keV 10.230 -f
Integral 0 = 230527
b-Nov-1985 14:57:37
Vert= 50138 counts ::::::::::::::::::::::::::::::::::::::::::::::::::(
..................................................g
Illl!*......!.!!I..!...!..!......r!..!!.I!...I.i..*
:::::::::::::::::::::::::ft u ::::::::::::::::::::
::::::::::::::::::::::::::-| *:::::::::::::::::::; ....................... .if 1 * . . . . . . . . . . . . . . . . . ^
4- 0.480 Range=
175Preset^ 100 se c E
D i s p s 1 E 1 a p s e d s 1 00 s e c sa:-- •••:---: :::::::::::-:--"--:;-----::::: -::::::::::::;:::::::::::::: ::::::::::::::::::::::::::::::
^::::::--:: ::::: '-SAMPLE::^w:::::--::: : ::;: : i;i: :: ;;:;;;;!;!:;;i:;;;:;;;;::i;;ii;;;!;!;ii:ii;i;:;;;:;;;;;:;:;;::PHOTO;:3002:;;:::::::::::::::::::::::::::::::: ':::: ::::::::::::::::::::::::
t.............................................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - . - - -
^Ca::::::::::::::::::::::::::::::::::::::::::::::':::::::::::::^:^:: --^ :':::::::::::::::::::::::..B. .......................................................•••.•••••••••••••••••' . . . . . . . . . . - . . . . . . . - - . - .
•:.'-::-::::::::::::::::;::::::::::::::-:::::: :::::::::::::::::::::::::::::::::: ::: .:::::::::::::::::::::;- ^::::::::::::::::::::::::::::::::::::::::.:::::::::::::-:::::::::::::::::::-::::::::ftu:::::::::::* *: : - : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : . : : : : : : : : : . : : : . : : : : : : : "rv : : : : : : : : : : : *****MVWM*'"HM*'''* M fv^\u*x M ** j t * r ii M m M ri fi* - ' - * * - - * ' - - ' r" '-^^." ** | m*t**; : : : : :
10.230 keV 10.230 -^ Integral 0 - 154934
b-Nov-1985 15:23:38
Verts 5000 counts D i sp*Preset* Elapsed
100 sees 100 sees
Au: Hu:
0.320 Ranges 10.230 keVI n t e g r a l 0
10.230 -f-
214651
b-no v- 1 ^aD i D : J J : 4U
Vert- 5000 counts
; ; — ; ; ; - - : - - - : ; - ; ; - ; ; - : ; - ; ; - ; - - - - - - - - - - - - - - - - - - - - - 1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .- . . . . . . . . . . . . . . . . .,
i;i.: ; ::::: !; :Mg;::;; : iii :Au : "" ::::::: " : " : :'i;;!:;!!;'::;;;* .fi S [1:1^^:^:1:^:1:1........ ....... " lt *|-ijj* i |V ••••••••••••••••m
4- 0.320 Range=
176 Preset* 100 sees
D i s p a 1 Elapsed* 1 00 s e c s
:::::::::::::::::::::::::::::SAMPt.f :: 5Wi:--:::::::::^::"--::::"--|----":"::"""::;i:;i;;
:aii:iii!iiiiiiii;iii;i:i;iPHOrO:ii50R2;i:iliiiiii:::iii:iiiii!ii;iii::':;i :.ii;;::':i;i!ii:::
*: ....................................................................................................'
t- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........................................................
-;Ca; : ;;:;:;;;;;;;;;;;;;:;i;;;;;i : ; : ;;i;;;;: : ;;;;;;; : ;; : ;; : ;; : ;;; : ;;;;; : ;:;::;; ::::: ;; : ;;;;; : ;;i;;;;;:aw:::.:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: :-;:::::::::::::::::::::* :::::^::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::-;:::::::::::::::::::: ,. ,....' m...^.......................................................................................
** '••f *-*\LLp. ——— HFf-trr^diMtfKMiii'rinirtKM.tinnnxwiu* ^^'irVj:::-
10.230 keV 10.230 -) Integral 0 = 160142
S-Nov-1985 15:59:53
Vert' 5000 counts
.....................................................m
.................................................... 9
;;;;;;;;;;:;;;;;;;;;;;;;;;;;ftu;;;;;;;;;;;;;;;;;;; ............................. v....................::::::::!::::Mg::ftu::^ ^::::::::::::::::::'. . . . . . . . . . . . . . .* i *-f jrm ^ "-Ttjjr^ttjjat^j^
4- 0.320 Range=
Preset' 1WW sees Disp- 1 E 1 apse d = 100 sees
r a ............ ; .. : ...... :; .......... ..... ;::: .. .... : . :::::: .. :;: . :::: ... : . : . ;::::: . : . ::::::::::::: .. :::
^::^^--^-SANPLE;-6N^- :: ; :: - :::: ;;; :: :;;;; :: ; ;: i; : ;:; : ;;;;;;; : ;;;;; : ; : ; : : :: ;;;;;;;;;;:;;;;:;:i-i;ii;:i:PHOTO:::6002:::::::::::::::::::::::::::::::::::::::::::::::::::-:::::::::::::::
j . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - .
Ga:::::::::::::::::::::::::::::::::::::::::::-::::::::::::::::::::::::::::::::::::::::::::::::::::: h* 'i::':: ::: ::::::: ::::::; :::: ::::::::::::::::: ::::::::: ::::: ::::::::::: ::: :: :: :::::::: ::::::::::::: :
^ x::::-::::::::::::::::-:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: Au:::::::::: •- . : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :^tVi : : : : : : : : : :
10.230 kev 10.230 -f Integral 0 = 201396
-Nov-1985 16:08:43i
rt= 10000 counts Di
iii;!i;;;!i;!ij;:ij^
::::::.: :::t::::::::::flui:::::i:::::::::::ij^i^-ii!* j Ufl u "^ *| '^-C i i^i^ir^
sp = 117
iiiSAMP :::pHOT
^7
IE Di
i
•i'* 6t
^Wi: "105
Pr El
e a
se ps
te fi"
100 sees 100 sees
IllllillillJill!-0.320 Range* 10.230 keV 10.230 -*
Integral 0 * 204683
8-NOV-1935 09:29:57
Vert- 5000 counts Disp- lPreset s Elapsed-
100 sees 100 sees
;Coi
SAMPLEPHOTO: 7001-
8.320 Range- 10.230 keV
Integral 010.230 -^
171877
S-Nov-1985
Vert = 50
:::::::::::::::::::::::::fi ~. 1 1 1 ; ; r ; '.'.'. '.'. ~. ~. ~. '.~. ~. i ~.~. ~. ~. ' ' ' '
::::::::::::::::::::::::::* iiiiiiiii-iiiiiiiiSiiiii
4- 0.440
09:56:47
30 counts ::::::::::::::::::::::C
. . .. ... .. .. ... . ...... , t
j.....................-, . . . . . . . . . . . . . . . . . . . .,. . . . . . . . . . . . . . . . . . .
a . . . . . . . . . . . . . . . . . . .:::::::::::::::::: -* j. . . . . . . . . . . . . . . . . . .
Range s
D i s p = 1
a:::-::::::::::::::::-:::::::::::::::::::::
*;!:;ii;i-::;;::;:i;pHOTO:ii800?
L-a::::::::::::::::::::::::::::::::::::: B * . : : : : : : : ; : : : : : : . . : . : . . : . : . . . . . . . . . . . . .
m M".'" "" ".'.".'.'.".'.'.' '.'.'.'.'.'.'.'.'.'.'.'.'.'.'.l'.
*. : : : . . : : : . : : . : : : . . : . : . . . . . . . . . . . . . . . . . . t ,......................... ............v \
10.230 keV I
Preset = Elapsed
100 sec 100 sec
Integra l 010.236 -f
208637
8-Nov-1985 10:07: 15
Vert= 10000 counts;:;;:;i;:;:;;iii;:i;;;;i:;;;;;iii;:; :: ; :: ;; :::::: ;c
...................................................m
..................................................B
:::::::::::::::::::::::::A U :::::::::::::::::::: :::::::::::::::-----:::::::T:::-----::---; ::::: :.:::::::::::::A1::::::* -::C1 :::::::::::; :::::::::::::::.....:;:^ ^..*.:::::::::::;
4- 0.440 Rarlge =
Preset= 100 sec;D i sp s 1 Elapsed= 100 sec:
3...................................................................................:.......:.:.:......:
j........................................................................................................
;;;;H;;:;; :::: ;;;;;; ; ! ::: SlHMPLE:::9W-"--"""-:-"":-::::::":::::::::::::::::::::::::::
:::::::::::.::::::::::::::PHOTO::9081--2:::::::::::::::::::::il:i::;il:li::iiii;:ii::ii:.:
i - - -- -- - -- . - - . -- -- -- - - - -- - - - -- - - -- - -- -- ••- .- -- --- . . .. ... .. . . . . . . . . ... . .. . . . . . .. .. . . . .. . . . . . . . . . ,. . . . .
1* m. .'. '. '. '. '. ' '. '. '. '. '. ' ". ~. , '.'. '. '. - - '- - . . "- - - - ' '. '. ". ' ' '. '. '. '.'. ' '. '. ' '. '.'. '. '. '. '. '.'. '. '. . '. I " '. '. '. '. '. '. '. '. ". '. '. '. ; 1 1 * i ; ; ; \ ; ; ; ; ; i ; ; ; ; ; ; ; ; ; ; ; ; ; ;. g......................................................................:.::::::.:::::::::::::::::;:::
1 0 . 230 k e V l ij . 230 -^ Integral 0 = 300876
~~22-Nov-~i9~85 i 3": 19:21""
Vert s* 2000 counts D i sp
:.. ..:...::::::::::::.::::::::::::::::::::.::::::::::.:::::..:.i ................................................... ...........j,
T.!!.'!'!"r!r!!r!!!!!iII"l!!!I!!l!'!IItI!!miI!l.'I.X.I....J*
4- 0.090 Range= 1C
179 Preset= 100 sees s 1 Elapsed* 100 sees
a ::::::::::: ::::::::s^MPLE:-:N-i0:;;;;;:;;i;; ; ;;:;;;:;;:i : ;-;i;;;;;;;;i;;;;;;: :::;:: :.::::::-::::::::PHOiO:::1001-2::::::::::::::::::::::::::::::::::::::::::
m . ........................................................... ..............................|:Ca::::::::::::::::.:::::::::::::::::::::::""":::::::":."":::----:"'"":""-::""" '* * . i '. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - . - . . . . . . . . . . . . . . . . . . . . . . . •. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
).230 keV 9.798 -f Integral 8 * 1264
8-Nov-1985 10:26:31
Vert* 10000 counts;;;;;;;;;;;;;:;;;;;;;;;;;; : ; ::: ;; : ; ::: ;;;;;;;;; :: ;c
...................................................a
.................................................. B
:::::::::::::::::::::::::Au:::::::::::::::::::? ::::::::::::::::::x-vr* V"."iV.*;r'^'V*
4- 0.440 Range=
P^eset= 100 sees
Disp=l Elapsed' lEiQsecs a--:::::::- : ------::------:--- •••••-••••-::- - ••:--:--::;:: ::.--: ••:::::::::-::;::::::;:-:-::-::-::--
;;;i;i;;;ii : i: : ;:i;i;i :.;sflMPLE;iiiw;i!i;!i;;:;;ii : i;;;!;i;i;:;i;;;;;!i;:;;;i;;;;iii;;ii;;: ::(:::::::::::::::::::::::PHOTOi::1101--2:::::::::.::i:::::::::::::::::::::::::::::::::::::::
.........................................................................................................;
ea::;::;;:;;;:;:;;::;;:::;:;;;;::;;;;;;;;;;;;;;;;;;;:;;;;;; 1 ;;;;:;;;;;;;;;;;;;:;;;;;;;;;;;;;;:;;;;;;;; *^::::;;;;;;ii!;:i;!:;;;;;;;;;;:;;;;i;;;i;i;;;;;;;;i;ii;i;;;;;;;;i;;i;;;;;;;i;;;;;;;;;;;;;;;;i;;:;;;; :: ^ p...................................................................................................
' : '. ' ~. ' '. ~. '.'. ~. '.'. i ~. 1 1 ~. 1 1 1 ' 1 1 '. ; : : ; i : 1 1 : i : : ; : : : : : : : : : : : : : : : : ; ; : ; . ; r r : : ; : : : : : : : : : : : : : : : : : " : " : : : : : : : : : : : : : : i : "i...................................................................................................
10.230 keV 10.230 ^ Integral 8 = 332460
C.C.-HO v-j. tio u:dJ:lc!
Ve r t = 500 counts Di s p
...............................................................(
:::::::::::::::::::::::::::::::::::::::*/:::::::::::::::::::: :::::::::::::::::::::::::::::::::::^ -t^.:::..:^:^:::^
4- 0.000 Range^ 16
•j H A Preset s 1U0 sees 3=1 Elapsed^ 100 se c s
: a .::::::::::::::SftMPLE :: W-12::::::::::::::::: ""-- : ""-- : " :::: :"" ::::::::::
:::;:;:;;;:::::::pHOTo;;:i20i-2:;::;;;i;;i;;;;;;:;; : :;: : ;i;; : ;;;;;;;:::;:!;:::
,..............................................................................................
m ..m :..............................................................,.........................
ir*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::* ^:i;;;;;i;i;:;ii;^H;;;;;;;i;i:;!ii;;;i;;;i;ii;;;;i;;;;:;;:;;:i;;;:;i;;;;:;:;;:;--;i
^^i^i*^***^rf*V**A*^IU*^"V'MMUV*^**^l*;** jy*ii*^***V^*^^ M^OM^ ; ;
1.230 kcV 9.790 -^ Integral 8 * 295
8-Nov-1985 10:43:01
Vert* 10000 counts: ; c
i ' -*
. . . . . . . . . . . . . .. . . . . . . . . - . . . . . . . . . . . . . . . . . - . . . . . . ,
::::::::::::::::::::::::: Au:::::::::::::::::::.''........................ -^ ^.......,...........
^- 0.440 Ranges
D i s p s 1
a : : - ::
:: : :: *.
i; \ iif *- - - . . .
( ..........................Ca:::::::::::::::::::::- * - ' ' ~ " - ' - ' - - - ' ' ' - - * ' ' ' '
i . . . . . . . . . . . . . . . . . . . . .
10.230 k t
Preset=
E lapsed
SfiMPLE PHOTC
13W 381
10U sees 100 sees
Integral 8l Ci. 230 -f
326313
1
S-Nov-1935 IE
Vert* 5000
mrnmrnm
):
c
59:23
ounts D i s p C a
B
.................... f*)g........py ....................
4- 0.000 Range*
z iji 3i
sF5
HMPLE HOTO 1
Pr El
14U 401
es ap
1 i— ^
et : secJ-
100
180
10.230 keV 10.070 Integral 0 * 202
sees sees
A us*
946
8-Nov-1985 11:17:46 " ' " "~ "
Preset= 100 seesVert* 10000 counts Disp* 1 Elapsed= 100 sees
:::::::::::i::::::i:::::::::::i:
::::::::::::i:::::::i
!"*iii."!ri""* *"***"*
!I!mi!IIIl!!!It!II
::::::::::::::::::..
i::::::::::::::::: 1. . . . . .j .^: : [^^
::i: : ::::: :
llll'. li ' . l".
ii::::::::::
•iiiiiiii:
::
•iu*
S'u?*""
l:::::::::::
: : :::i::i:i:
i:::::::::::
: ::::::::::i:
iilCl::::::: i: -^p^i^^^
:
B 1
B
' 2-3
m m - .
;:
j:
N ^i : i : i
4- 0 . 000 Range * 1 0 . 238 l
-.AM F•H 0'
;;;;;;;;
L'EJilSU0: 150
: -
: ". : u i , - - - -
eV 10.070 -)-Integral 0 = 34 329 2
tf-Nov-1985 1 1 : 34:46
Vert* 5000 counts Dlsp= l
182Preset^ E 1 a p s e d
100 see 1 00 s e c
:::::::::::::::::::PHO FO:: 1 60 1 -2:
4- 0.000 Range= 10.230 keVIntegral 8
10.070 -^ J 66766
8-Ncw-1985 11:49:58
Verts 10000 counts Di ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::C
::::::l:::::::::::::r . . .. . ... .. .. .. . .... . . t
...,,...............m"II^IHI*---- *"*
g:;:::!;;:!;
i f
^~**
4- 0.000
. . . . . . . . . . . . . . . . . . . .. M
j :::::::::::::::::::: p . . . . . . . . . . . . . . . . . . . . .
'•iCliiiiiiiiiiii'
spa
- 1
Range* 1C
s 1Preset* E 1 a p s e d
100 sees 1 00 sec s
PHOTO ::17U 1-2.
e **-" U s**-
10.238 keIntegral 0
10.070 -^ 483533
S-Nov-1985 12
Verts 5000
;i;;;:;.: ii:::::::;:i::::::i::.: ;i:ft
. . . . . . . . . . . . . . . . . . . . ^ . . . . . . . . . 4
:!:f::::;i:ii;i::::i' 'ii-jSi* r:::::::::::::::::::. ** i
4- 0.000
: 06 : 1 3
counts Di
......................m
t. . . . . . . . . . . . . . . . . . .
'a]-;-:;;;;;;;;' 1
Range s
183Presets 100 sees
sp=l Elapsed= 100 sees
:::::::::::::::::::::::::::SAMPLE :: 18N :::::::::::::::::::::::::::::: .::: i :::: :-:: :: : ::
V:::::::::::::::::::::::::PHOTO:::1801:::::::::::::::::::::::::::::::::::::::::::::::
| W *-~rjfJ*mm -wrn^f J V
10.230 keV 10.070 -^ Integral 0 = 307931
S-Nov-1985 12:21:20
Vert* 10000 counts::::::::::::::::::::
::::::i: ::::::::::i
iiliii; iililiililli*. . . . .'.'. '.'.'.'.'.'.'.'.'.'.'.'m
....... ...........—
siiilpi i
i ;; ; ;; ; ; ;^r*
::..::::: :::
fi.j '"l
4- 0.000
:: :::::: •^ji-i
W*' P"
Preset^ Disp=l El apse d =
C c
a
m
m
(
t t
\
^ -3 : : : . . . . .
B . . . . .
,. . . . .
•^••1
Sp
Ar:H C
PL Tf
li:
E; ii'i lyi9i 1
lir^
i i: i i-C": ;
IE IE
)0 50
sec-
sec
jiii''
ss
Range s 1 0 . 230 k e V l 0 . 070 -^ Integral 0 = 333026
29-Nov-
ART Vert'S
;;;;:;;:;.: ;;; :"Mc
t :::: ~::::::::::'fc
4- 0.
1985 14:53:47
2008 counts I :::::::::::.:::::::: :.: :.::::::::(-
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -B
.............................. . . . . m
J:::::::::::::::-:::::.:.: ::::::::..
;:::::::::::::::::::::::::::::::::-
160 Flange---
184Preset 100 sees
H sp s 1 E lap se d s 100 sees. a ................ . ............................. .............. .....................................
*............................. . . .. .................... .....................................
.:::::::::::::::::::::bAMPl.E:::c:lN::::::::::: ::::: :::::-:::::;:iiil:::i;;!;.;;;:::;;;:; :::::: :::::::::::::::pHOTO :: 2lMl-r' :--: ; :":: :':::"::::::::::::::::::::::::::::::
-i, a ..............:..... ...: . .......::::...:.....:: .....::::::::.::::.:::::::::::::::::::::::: ..• r .....:.:::......::.:::.:..:::::.::::.:..::::..:::::::::::-::::::::::::::::::::::::::::::::::::::
•. •••; - -- ............................ ................. ......................................
1 ; ; - ; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . - - - - - - - - . . - . . - . . - . . . . . . . . . . . . . . . . . . . . . . . . . .
10.230 keV 10. 230 -^Integral 0 = 95529
29-Nov-1985 IS:01:22
ART Vert 2000 counts D i sp* l
Preset = E l apsed =
100 sees 100 sees
;SAMPLE;;22W:PHOTO-2201-2
Mg;
•-c:. \i, a
HU:
'*ft*s
0.166 Range* 10.23U keVI n t e g r a l
10.230 -^ 160569
29-Nov-1985 15:18:11
ART Vert* 5888 counts Disp= l
P^eset= E lapse d
108 sees 188 sees
!Cai
PHOTO
0.160 Range* 18.238 keVIntegral 0
10.230 -f 15989S
185
^Z-Mov-iygb 14:23:41
Vert- 5888 counts Di
:::::::.::..:..::.:::::.:::::::::::::::::::::::::::::::::-.f
lliiliiililliii:
4- 0.000 Range*
T X KS- ^J \r
Preset * 180 sees sp s 1 E 1 apseds 188 sees
.a:::::::::::::::::::::::::::::::::::::::':::::::-'::-'-"':::::::::::":.'".'::-:."".':"-"-":""-'"
^;;;:li:j:!:i;;;i;ii;^
18.230 keV 10. 110 -f Integral 0 " 169509
22-Nov-1985 14:36: 18
Preset s Vert" 2888 counts Disp* 1 Elapsed*
.ii;iii;;.: ;.: :i!i;;:Mc
m
i :::::.
Ai
" * u .
*v
4- 0. 888
J ! :: "
': : :;
,. . . .... .
O- . .... . .. .... ,. .... . .. . . ......
: : ::: /SAMPLE
i :;;. :.:\ . PHOTO
. ". ' ' 11!
Ca: : :; : :: '
: :: : :: :
a m . . . . . . . . . . . . . .
^ri ;- M-*
188 sees 188 sees
i ; ;; ; ; ; ; ; :; ; Au*"~ ^"^~——— ——— *kP^^NT^^^^^^W^^
Range" 18.238 keV 10. 118 Integral 8 * 141
a
5"
*-*
74
187Preset- 10U sees
Verts 5080 counts O i sp- l Elapsec^ 100 sees;i;i;!;;i;i!iii;iiiii;i:isTii;;i;iii;ii:ii;!ii.:
WMM^ ^)MMMsbWPL^\25F
l ••••••••••-•••- - - - - -- ---
'.'.'.'.'.'.'.'.'.'.
:: :: ---;:.: -V
:Mg;
4- 0.000 Range= 10.238 keVF0.110 -^~
Integral 0 = 254429
22-Nov-1985 15:37:05"
P^eset= 100 sees
Vert* 5000 counts D i sp- l Elapsed= 100 sees
liiillliillll;;!;!;;!;^
'.".i'.::::::::::::::::::::::::::::::::::::::::::::::::::::*
S i":Pu '.::::: :::::::::::::
0.000 Range* 10.230 keV
Integral 0
10. 110 -l 119467
Verts 10008 counts Di
.................... .......... . . . . . . . . . . . . . . . . . i
4- 0. 080 Range*
188Presets IFnj sees
sp* 1 E lapsed s 100 sees
a..............................................................................................
10.230 keV 10. 110 -^Integral 0 s 280450
26-Nov-1985 09:14:53
5000 counts D i sp* lPreset* Elapsed-
100 sees 100 sees
s i
0.000 Ranges 10.230 keVIntegral Q
d b - M o v — l y b w- H y : ci J : 4 i
189P r e s e t z 100 sees
V ert= 5000 counts D i s p * 1 E 1 a p s e d s 1 00 s e c s :::::::::::::::::::::::::::::: :::::: ::::::::::::: ::::::(-a x.:::::::::::::-::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
mmm
i;:;;:;!;!;;;;!;;:*
:;;ii;:-^^^
J::::::::::::::::.:::::::::::.::::::
. . . . . . . . . . . r-4 . . . . . . . . . . . . . . . . . . . .
f4- 0.000
••••ri
....
l"
, 4 .. .................
B ' ' ' " ' - - - - - - - - - - -
::i!i;::!i;il^iirai:^
•w^iv ——————— i^^:^^^^^,^^::::::::::.:::^!^.::
Range= 10.230 keV 10.110 -fIntegral 0 ^ 339452
26-NOV-1985 09:37:56
Ve^t= 5000 counts Disp= lPreset= Elapsed
100 sec 100 sec
!SftMPLE-i30F
••Mg
0.000 Range= 10.230 keVIntegral 0
10. 110 -^. 351386
26-Nov-1985 "09:50:"!!'
V e r t = 58 00 c o u n t s D i s p *
190P r e s e t - Elapsed
l EI 0 sees 100 sees
;S AMPLE i 3 I
:Mq
iflu
4- 0.000 Range* 18.238 keVIntegral 0
10.110 -f261359
^b-nov-iyy
Vert= 5
:::::::::::::i:
:;;i::ii ;;i;;; rig• ..•••II 1 1 1 I 1 1 i
D 1U: k
000 C C
Aui '.
m *
J4
u
ii*
4- 0 . 000 Ra
Pre set = E lapsed
100 sees 100 sees
Ga
PHOTC 0
Pu-"Pe
Integral 010.110 -f
274033
c. o - 1 1 u v — o. y o O i U : 1 *4 l L D
191; Presets 100 sees
Verts 5000 counts Di sp *
' " * * " * * * * " " *
i!!!!!!!;!?!1 Illlllll II: ; : : ; ; : : ; ; ;
. . . . . . . . . .m
Ullllll 1
&J&
Ift 1•1
- 1 1 : :
J 1:
xiiii.. : ' t : "*
4- 0.320 Range =
Cal- 1
r - *
Calb
t ;
*"V-
1 E lapse d s 100 sees
'.'.~.
SAMFF HO T
LE;
oil:33
J30
i |
r**-6^
1 IIII IIII 1
F ;i ; i iiii i•2 iiii i
::^ '^"";;
••mr**
; ;
^i-l
"11 i I
1 1 . . fm. .
19.230 keV 10.230 -^
Integral 0 s 224680
26-Nov-1985 10:25:48
Verts 5000 counts
: : : : : : : : : : : : : ' *•••m^^f*r
i:::::::::::::::::::::::::::::::::::
llll :: .: lllfl
.... .... . .*
14- 0.320
y...................
a................... ...................a
Preset^ 1 00 sees
D i s p z 1 E 1 ap s e d s 1 00 s e c s•a-------:::----:::::----:-::::;-::::-::::::::::::::::::::::::::::::::::::: ••::;:::::::.::::::::::::::::
::::::-:::- ::-:::::: PHOT 0::34R 1-2::::::::::::::::::"::"::":"":":::-"""-::"":... ...... ........ . -.. - .......................... ... . . ..... .... ... .... ... .... .
C 3 :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: ; :; : :;;; : ;: ::: ; :.:::
' .Il : li; : lli;illlli;il : i;;:i : :i;illllllllllli;illlllli;illlllllllli;il:;ili:l: ::.::.Hu::ll:llll:
*V^J^*^ I-AIVT ——— -f~r *s v^^mf •••' ^ ^^ •iu^i^i atjiu, , ^ '•"* 1 "v*.i^ ; ; ; ;
Rang e s 10.230 k e V 10.230 -}- Integral 0 = 332435
26-Nov-1985 10:37:26
Vert= 5000 counts
:::::::::::::::j ':::::::::::::::::::::::::::::::::::................ ..................................m
,. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . '.'.'.'.'.'.'.".'.l'.:*,'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.
18SP^eset= 1W0 sees
0 i s p - 1 Elapse ci - 1 00 s e c s
S?:!;!i;!Jii;i!!;ii!i!ii;!!i;!!lhiiii!i;;!;ii;;iii^;;;;;;;;;;;;;;ii;:;;;;:i:;i;i;M^
4- 0.320 Range= 10.238 keV 10.230 -^ Integral 0 = 309616
26-Nov-1985 10:48:21
Vert* 5008 counts :::::::::::::::::::::::::::::::::::::::::::::::::::::i
:::::::::::::M g :::::::::::::::::::::::::::::::::::::::::::::::::: j
: r ' : " : : : " " "*
... . .. ..... . . . h
^iilii-iiiH
^^
4- 0.330
. . . . . . . . . . . . . . . . . . . . . *
ij ::::::::::::::::::: i. . . . . . . . . . . . . . . . . . . . *::::::::::::::::::,
™**r t*wt**vp
P^eset= 100 sees D i s p * 1 Elapsed= 100 se c s
.3......................................................................................................
l ........................................................................................................
:::::::::::::::::SflMPLE : ^^bF :: : ::::::: :; :: ;:: ::: :ii:"::i : """"-""-::" : :.: ;;:::i;;ii:
:::i::iii:i;;':;;;PHOTOii.:3601-2::::::::::::::::::::::::::::.:::::::i;:i:::::::::::::::::
g............................................:........................... .................,...........
Ca : : ;:;;;;;;;;:;;; ;;;;i;;;;;;;:;:;;:;;;;;;;i;;:;;;:;;; : ;;;:;;;;;;;;;; : ;;;:;;:;; : ;;;:;;;;;i;;;;;;;;g...................................................................................................
;*::::::::::::::::::::::::::::::::::::::::::::::::::::::::::.:::::::::::::::::::::::::::::::::::::::::
* *. .. .. ...,. ......,.... ... .... ... .. .. ....... . .. ....... .... . ............. ... .... ... ...................
. ;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::flu:::::::::: ' ————— v —— ^vt^ii^^^^^^^.^^----;--^;.;;^^^^^^^::::
Range= 10.230 keV 10.230 -^ Integral 0 = 284968
26-NOV-1985 10:58:13
!83Preset= 180 sec s
Vert- 5(
Mg
'
r
' V-*:m***t*M*~
300 counts D i sp 3C* '-
— i
J
flu 1•r "
mm 1
^ ^X-^^-^r-'
t ;
^
C a :
A i Ift
1 - -
1
3ftMFLPHOTO
mf*
E is?7
E 1 apsed =
VT01-2
100 sees
m-t - ,- j--,-^~n u UU.U14- 0.320 Range s 10.230 keV 10.230 -f
Integral 0 = 305462
26-Nov-1985 11:12:04
Vert= 5000 counts D i spPreset s E lapsed
100 sees 100 sees
0.320 Range s 10.230 keIntegral 0
10.230 -f 252012
iib-Nov-l
Vert =
935 11:25:23
5000 counts
. ..-. . .. . .. .. ... j
'.'.'.'.'.'.'.'.r.'.'.'.".*
••••••••••••••f
i-
•- -
i-*i4- 0.
::;::i;flui-:.: -::'iiiiii:':'i:i J^wT- l ^rf^^^ii
. . , u
' V
194Pre:5et= 100 sees
D i s p s 1 Elapsed- 1 00 s e c s
* . . . . .. . . . . .. . . . . . . . . . . . . . ,. . . . .. . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .. . . . . . . . . . . . .
. t~ 2 .................................... .............................. ............................
. m . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . .. . .. . . . . . . . . ...................................,................ ..... . .. .. .. . .. . . . . . .. . . . . . . . . .. . . .. . . . . . .. . . . , . .. . .. . .. ,. . . . . . . . . . . . . . . . . .. . . .. . . . .. ... .. . ... . ,
* *:::: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::'::::::: - ::-.:::::::::::::::::::::::: ' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - ia ... . . . -. .. .. . .. . . .. . .. . . . . . .. . .. . . .. . . .. . .. .. . . . . . . .. . .. . . .. . .. . . .. . . . . . . .. . . .. . . . . . .. . -. . . ...
320 Rar,ge= 10.230 keV . 10.230 -^ Integral 0 * 221900
26-Nov-19S
Ve^t= ! ::::::::::::::::::::S
.......,...........fl
;;;;;;;;;;;;;MC...............a . . . . . . . . . . . . . . m
"*
r
4- 0.
- k
*
i
35 11:33:49 |
Preset= 100 sees 5000 counts Disp* 1 Elapsed* 100 sees•••- :-:--:--:--::-:-:::: r---::::::-::-:--:-::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::-::::::::::::::::::::::::
]]]\\--]]\\\\\ : \\\r-^
•''•••••••••'''•'•'•••••••'•••^:;;;s;;;;;;;;;;;; : ;;r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .,iiAuiiCltiiiiii:::::::::::.-::::::::. . . .- . . . . . m .......m
•^ -;;;;;;;;- --"i - '
. . -*
* ' '
• B1
t . ...: ...................................................•.••.•..-•....•.•..•••••••••••••••••••••.•••••••
** V^^-V-- —— - ••••••••- •••- -- fc |r - ............................... ........................
320 Range= 10.230 keV 10.230 -^ Integral 0 = 305274
c.?- ri o v- i :
ART Verts
::::::::::::::::::Mc
....................a
5000 counts Di
:::::::::::::::::::::::::::::::::::
;ii!i!l!!:i.Tv:ii!!!!!il!!!;i!i!iI^WWA^^.
195Presets 100 sees
s p - 1 E 1 a p s e d s 1 00 s e e s
g... ................................ .......................,....... ..... ,. ..........................
•* i:::::::::::.:::::::::::::::::::::::::::::::::::::::::;:::::::::::::::::::::-::::::::::::::::.
4- 0.000 Ranges 10.230 keV 10.110 -f Integral 0 = 181790
29-Nov-1985 11:31:20
ART Presets 100 sees Verts 5000 counts D i sp * 1 E lapsed s 100 sees
::::::::::::::::::::::::::::::::::::::::::::-:::^
::::::::::::::::::fv)
....................,
i!i;!iji!i^: ;ili:i : i:;;::ii!:i:
":::^:::::-:: PHOTO- 420 i-z:";;;;;:;;;;:; ;: ;;;;;;;;;;;;i;;;;;;;:;i;;;;;;;;;;;;;;;
;^::;;:::i::::i;::i::::ii:::::::::ii::::::i!i:;;:ii:::::;:;::i:;::;ii;::i:Ji::;i^
4- 0.000 Range= 10.230 kev 10.110 -^Integral C? s 141521
29-Nov-1985 11:38: 10
ART Vert= 2000 counts Di
:-^jsn iiiii*"^1
S::::::::::::::::::i:: : ::: : ;;i;;i:i;
i.......................... ......
f::: i *.:::::::::: :: :::: t** V........... . ....
^^U^^^M^i** *w f*^f
196Presets 100 sees
sp=l Elapsed- 100 seesg ................ ............. ........ .........................................................
.. ....... .... ... .. .. ... ..... .. . . .. . .. . .. .. ..... .. .............. .. .. .. ....... .... . .. .. ....... ...
:::i::::::!:;;:i:;:i:;:::::S AMPLE ;i42F::::::i:iilliii:i:':':i':':':i":':':i;::;i :.i;ii;:;;;:i:
" ri . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
*^ " njj JL ' *-*-* : : L: : ' . : : : " . ' .::::: ' : - ::::. :: .::':::::.:::."::'-":'-""'":"::''::"::::-":::"*^-*^^^*XVrfW^^"^-^"g^. ..--^^^.^ •i^ft.ft^.^^^^^"^,. -
4- 0.000 Range^ 10.230 keV 10.110 -^Integral 0 * 132833
29-Nov-1985 11:46:49
ART
Verts 2000 counts Di ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::r
;;;;;;;;;;;;;;;;;;MC1:::::::::::::::::::::::::::::::::::
t...................................
ISllB
Presets 100 sees
sps 1 Elapseds 100 sees
.a:;:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::;:::::::::::::::::::::::::::::
i ......................-— f|1111 *— .. - ....................................................
Pi;ii:i!!liilii!i!iiillliiii4- 0.000 Ranges 10.230 keV 10.110 -f
Integral 0 = 111060
197Vert" 2080 counts Di sp* l
Pr e s e t *E l a p s e d
108 sees l 00 sees
;SAMF'LF.;;01-1iPHOTOi':ill21-2
Mg:iAui La:
:C i
0.080
^M
RangeIntegral -1
9950-) 0
6-Bec-1985 09: 13: 17
5 Preset 3 188 sees
Vert" 2088
Mg
••a"
4- 0.000
counts Disps !
a - -
Au i Lai. " * *. . . . mmf . . . . . . . . . . . . . . . . . . . -, ;
,
isp
H MF lC T''
E lapsed*
E 81 IT J18-U-2
-
Range* 18.230 kcV
1U8 sees
9.950 -*Integral 4 z 0
29-Nov-
ART Vert =
iiii iiiiiiiili
:: ::::::::::::
1985
50
g
* *m \ fmu
13: 1'
90 coi
Aullc
3:21
jn t s
L
i 111111
D
C
.
m
B
^- 0.160 Range*
i s
a
-
P
L d
nii:
::::::::::
Ills ijlr-
•ipAp
1
firH(
98
IP LI )TO
: :
ii
0
:::
40 86
pE
-8 1-
res 1 ap
8J 088
et:
sec
2 i!
i*
::::::::::
100 sec; 100 secj
10.230 keV 10.230 -\- Integral 0 = 141007
5
s
29-Nov-1985 13:38:54
ART Vert" 2000 counts D i sp* l
Preset = E lapsed *
100 sees 100 sees
Hi
Ca
jSAMPLE iPHOf J
3-131:: 1 —
0. 160 Range r 10.230 keV
I n t e g r a l 0.230 -fr.133322
29-Nov-1985 13:46:15"199
ART Vert* 2000 counts Disp= l
Preset = Elapsed
100 sees 100 sees
SAMPLEI:i:01-48:PHOTO;;
Mg:
•C liS i
0.160 Range- 10.230 keVIntegral 0
10.230 -f 149683
29-Nov-1985 13:57:24
ART Vert* 2000 counts Disp= l
Preset = E l a p s e d
100 sees 100 sees
S i
SflMPLEiii01--50:
PHoro;;i50i-2;
:Na:iAl Hu:
0.160 Range= 10.238 keVIntegral 0
10.230 -l 162077
14:12:56
Preset = 100 sees5000 counts Elapsed 100 sees
SftMPLE:: 01 -5 lPHOTO-1511 -2
f JW^R.=^nqe= 1W. 230 keV 10.230 -l
Integral 0
29-Nov-1985 14:20:4
Preset*El a p s e d5000 counts Disp
SAMPLE-01-55
0. Ib0 PangIntegra l 0
10.230 -f 147074
29-Nov-1985 14:28:22
201ART Vert = 2000 counts D i sp
ii;;i;;; ; ;;;; ; j ; ;i ; ;;i;;i;;;i;;;;ca;;;;;= i
Preset* E l a p s e ci
0.160 Range* 19.230 keVIntegral 0
100 sec 100 sec
::::;;::::::;::Mc . . . . . . . . . . . . . . . . . ^
... ....... ... .. .. b
; ; ; : i : r : ; : i : ; : i "*: :^iilVfc*i**rrf*
|::::::::::::: ••--•-- -H
•••••-•••••*
^^*
. . . . . . . . . . . . . . . . . . . . . .,
u :::::::::::::::::::*
p . . . . .. . . . . . . . . ,. . . . . . V : - : : :: ::::::::::::g...................
t .................U
VjiiiiiwiSii^-
*:::::::::::::::::::::SAMPLE:::01 '62:::: : :::: ::::::::::::::::::::::: ::::: :: :::: :: :::::::::::::::::::::: PHOTO : !1 62 l~2: i :: - : ' :::::::::: " :: " : -: : " ::::: " : ::;;: - i!
u. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
;Ca::::::::i: ;;i:i::::::: :i:::;:;i:i:::::: ::::::-.: :: ::::::-:::::!:: : :::::: ::::::::::::::::
:* ;:::.:::::::::::::::::::::::::::::::: :: ::::::::::::.:::::::;:::::::::::::::::::::::::: ::::::: t . . . .. . .. .. ... .. ..... .. . . .. . .. .. ... . . . . . . . .. . . .. ... . . .. . .. . ^ . . . . . .. .. . .. . . . . . . . . . . . . . . . . . . .. . . . .^:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::/^,:::::::
10.230 ~^- 10350b
29-Nov-1985 14:39:21
ART Ve^t = 5000 counts Disp= l
Preset = Elapsed
100 sees 100 sees
SHMPLEiieil-66iPHOTOi.iie.61-2
Mg:
ifiu; La-
0. 160 RangesI n t e g r a l 0
2J0 -f
146332
29-NOV-198S" i"5: 18:27
ART Vert- 2080 counts Disp* i
Preset = E l apsed
100 sees 100 sees
;SflMPLE : ;0i-7i;;:;;;::;;";: ::::::
Mg:
0.160 Range=
•ii-v
10.238 keVIntegral 0
29-Nov-1985 15:26:14
ART Vert= 2000 counts Disp= 1i;;;;::;::;;:-:::^^^
;;;:I:;;;!;;;;;;;;MC
i-iiiiiiiiiiiiiiiii^
: '- L,±?~"**i*mt
1:::::::::::::::::::::::::::::::::::
:::::::::::' i:::::::::::::::::::'
. . . . . . . r HC.-' 1 ' '- - - X O 1 1 '"" L. - - . .
a ...................................... m ....................................
4~ 0.000 'Range* 10.230 keV I n t e
Prese t = E l a p s e ci
It10 sees 100 sees
0
;^^;10.110 -^
143444
"29-Nov-1985 15:38:18"
ART Vert*
2035086 counts Disp* l
Preset* Elapsed
100 sees 1 00 s e c s
000 Range- 18.230 keVIntegral G
10. 110 -16721
6-Dec-1985 09:28: 12
Vert 2008 counts Disp* liiiiiCa;;;;;;;:
Preset* Elapsed*
100 sees 100 sees
0.0Q0 Range* 18.230 keV 9.958 -Integral'4 0
29-Nov-l*
ART Vert =
;i:;;;:;;;;;;;-:!;;Mc
. . . . . . . . . . . . . . . . . . . .,
. . . . . . ••••••^•j -j*?
. .wm ,^ JJJUX^™^
4- 0.C
335 15:48:43
2008 counts Di ::::::::..:. :::: ::::::::.::::.:.::: .f
J:::::::::.-:-:::::::::::.:::::::::: i................................... •••••••••••••••-•••••••••••••*
i:"ii!iii:Auiiiiii.: iiiiiiiii:':i . .. ... .. .. . . .. .. ... ..... .. . ...,- h
'•X^l ^^j^r11
J00 Range =
2(
sp= 1.0 •••- --•••••••• : --- : ;
:::::::::::::::::SAM
:::: :: ::.::::::pHO
, . . . . . . . . . . . . . . . . . . . . .
La::::::: :::::::::.n . . . . . . . . . . . . . . . . . .. * . . . . . . . . . . . . . . . . . . . k - - - . . - . . . . . - . . .
* i---------------;--:
1. ...................
* m:::::::::::::::".:V-'Vi^A***.*^*
10.230 keV
Preset = Elapsed
100 sees 100 sees
I n t e g r a l W
'•JWM^M'I MB*^ ^V*'
IcKiTe -f135386
29-Ncw-1985 15:55:57
ART2000 counts Disp= l:::::::::::::::::::::::::::::::::::js**;-:::::::::: "r:::::::::::::::::::::::::::::::::'-^ ::::::::::
Preset s Elapsed
100 sees 100 sees
;pHOTOi;;i88i-2 :::::
Ca
Fe:
0.000 Range= 10.230 keVI n t e 9 r- a l Q
10.110 -f 140933
29-Nov-1985 16:03:20
ART Vert- 2000 counts Di ::::::::::::::::^
:;!:!!::::::::::::MS
. -M. iMAliiW1^
1::::::::::::::::::::::::::::::::::
t::::::::::::::::::::::::::::::::::
:::::::::::; ;:::::::::::::::::::* ::::::::::* \::::::::::::::::::
205Preset- 100 sees
sp* 1 Elapsed- 100 seesr--:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
4- 0.000 Range- 10.230 keV 10. 110 -f Integral 0 - 124147
29-NOV-1985 13:31:43
ART Vert- 2000 counts Disp" l
Preset" E lapsed
11:10sees
:SAMPLE;;;23-17;;iPHOTOii3171-2:
Ca;
0.16Q Ranye* 10.238 keVI n t e g r a l 0
10.230 -f 105549
Appendix G
APPENDIX G - X-RAY DIFFRACTION DATA
206
APPENDIX G X-RAY DIFFRACTION DATA
This appendix contains the traces from the x-ray diffraction study.
A complete list indicating the sample depth and facies is also included.
Oriented clay size fraction (less than 2 micrometers) mounts were made
from the residue remaining after the acid digestion. These were analyzed
using the Rigaku D-Max-IIA automated horizontal x-ray diffractometer,
located at the University of Guelph, Land Resource Science Department.
The samples were scanned from 3 to 14 degrees 2 theta, at a rate of
2 degrees 2 theta per minute, and at a peak intensity of 800 CPS.
The numbers in the right hand column of each set of traces representl i
the sample number (eg. 2W) and the treatment used (eg. Mg , magnesium)i i
The majority of the sample traces shown were magnesium saturated (Mg ).
The potassium saturated traces provide no further information, hence
they were not included.
The ten angstrom peak found in many of the x-ray diffraction traces is
interpreted to represent the.clay^mineral'illite. No i other clay mineral
peaks were noted in any of the traces.
207
Appendix G Samples For X-ray Diffraction
Sample ID Field/Well Depth Cm) Facies
1W2W3W4W5W6W7W8W9W10WHW12W13W14W15W16W17W13W
19W20W21W22W
Wilkesport 560,07564.87569.09569.62571.45575.54578.82582.32584.94590.70597.41608.56607.97611.84615.19619.66623.93626.08629.41629.97633.98644.96
Anhydrite Algal Bioturbated Algal
Algal/Vadose a H
Pelletal/Algal M H
Algal Boundstone Crinoidal Algal Algal Boundstone Coral Floatstone Tabular Stromatoporoid Coral Framestone Basal Debris Calcarenite/Grainstone Basal Reef Debris Contact Goat Island Goat Island Formation
208
Samples For X-ray Diffraction con't
Sample ID Field/Well
23F Fletcher 24F 33407
25F26F27F28F29 F30F31F32F33F34F35F36F37F Fletcher 38F 40003
39F40F Fletcher
33323
41F Fletcher/i or 40001 42F43F
Depth (ra)
415.33 418.62419.59420.28421.00425.72427.53431.55434.39435.06436.13438.29442.00444.39427.58 431.29436.57432.98
424.51429.72432.28
Facies
A-l Carbonate M H
Guelph-A-1 Contact ? Bioturbated Guelph? "Green Shale" Eroded Reef Top
Reef Core (strom.-coral ,, framestone)
Eroded Reef Top
Reef Core (strom.-coralVadose Silt? framestone)
Eroded Reef Top
Reef Core (strom.-coral framestone)
209
X-RAY DIFFRACTION TRACES- WILKESPORT PINNACLE REEF
10 A0 ILLITE PEAK
14 12 1O 8 6
DEGREES 29
1W Mg •n-
2W Mg -n-
3W Mg
4W Mg
5W Mg
6W Mg
-h-h
•n-
7W Mg
8W Mg -n-
210
X-RAY DIFFRACTION TRACES- WILKESPORT PINNACLE REEF
10 A" ILLITE PEAK
9W Mg•n-
10W Mg
11 W Mg
12W K
911
X-RAY DIFFRACTION TRACES - W1LKESPORT PINNACLE REEF
10A0 ILLITE PEAK
1O 8
DEGREES 20
13 W
14W Mg*"1"
15W Mg -n-
16W Mg"1"1"
17W
18 W
19 W Mg/*"1"
2OW Mg •f-h
21W Mg
22W Mg-n-
212
X-RAY DIFFRACTION TRACES - FLETCHER PATCH/BARRIER REEF COMPLEX
10A0 ILLITE PEAK
l l
23 F Mg •n-
24 F MQ++
14 12 10 8
DEGREES 29 213
X-RAY DIFFRACTION TRACES-FLETCHER PATCH 7 BARRIER REEF COMPLEX
25 F Mg
26 F Mg
214
X-RAY DIFFRACTION TRACES-FLETCHER PATCH/BARRIER REEF COMPLEX
10 A0 ILLITE PEAK
27 F Mg •n-
1O 8
DEGREES 29 215
X-RAY DIFFRACTION TRACES- FLETCHER PATCH/BARRIER REEF COMPLEX
10A0 ILLITE PEAK l
1O 8 6
DEGREES 29
28 F Mg •n-
29F Mg-*"1"
30F
31 F Mg -n-
32 F Mg •n-
33 F
34F Mg-1"*-
35 F Mg
36 F Mg•4-4-
216
X-RAY DIFFRACTION TRACES — FLETCHER PATCH X BARRIER REEF COMPLEX
10A0 ILLITE PEAK
l l l l
37 F Mg
14 12 10 p 8
DEGREES 29 217
X-RAY DIFFRACTION TRACES - FLETCHER PATCH X BARRIER REEF COMPLEX
10A0 ILLITE PEAK
38 F Mg-n-
39 F Mg-n-
40F
41 F Mg -*"1-
42 F Mg -n-
43 F Mg •l--h
218
Appendix H
APPENDIX H - CALCULATION OF WEIGHT PERCENT INSOLUBLERESIDUE
^ * qr*. J. V
APPENDIX H CALCULATION OF WEIGHT PERCENT INSOLUBLE RESIDUE
The following table contains the results of the weight percent insoluble
residue calculations performed on the samples subjected to the acid dig
estion procedure. The residue weight represents the air-dried weight of
the less than 2 micrometer fraction obtained from centrifuging the material
remaining after the carbonate digestion was completed. This material is by
no means pure clay. It is likely to also be made up of sulphides, kerogen,
and possibly some less than two micrometer quartz and feldspar. Another
error which may be inherent in this determination may be clays and
insoluble material which were lost during centrifuging (dumped clays), or
those that were lost during the transfer to drying pots. These errors can not be quantified.
The bulk sample weights were measured using an open pan balance. The residue
weights were obtained using a Sartorius analytical balance.
220
CONVERSION FACTORS FOR MEASUREMENTS IN ONTARIO GEOLOGICAL SURVEY PUBLICATIONS
Conversion from SI to Imperial
57 Unit Multiplied by Gives
Conversion from Imperial to SI
Imperial Unit Multiplied by Gives
Ig/t
Ig/t
LENGTH1 mm1 cm1m1m1km
0.039 370.393 703.280840.049 709 70.621 371
inchesinchesfeetchainsmiles (statute)
1 inch1 inchIfoot1 chain1 mile (statute)
25.42.5403048
20.116 81.609 344
mmcmmm
km
AREA1 cm2 1m2 1km2 lha
0.155 0 10.763 9 0.386 10 2.471 054
square inches square feet square miles acres
1 square inch 1 square foot 1 square mile lacre
6.451 6 0.092 903 042.589 988 0.404 685 6
cm2 m2
km2 ha
VOLUME1 cm31m31m3
0.061 0235.314 7
1.308 0
cubic inchescubic feetcubic yards
1 cubic inch1 cubic foot1 cubic yard
16.387 0640.028 316 850.764 555
cm3m3m3
CAPACITYl L 1.759755 pints l pint l L 0.879 877 quarts l quart l L 0.219 969 gallons l gallon
MASSlglg1kg1kgIt1kgIt
0.035 273 960.032 150 752.204620.001 102 31.102 3110.000 984 210.984 206 5
ounces (avdp)ounces (troy)pounds (avdp)tons (short)
* tons (short)tons (long)tons (long)
1 ounce (avdp)1 ounce (troy)1 pound (avdp)1 ton (short)1 ton (short)1 ton (long)1 ton (long)
0.568 2611.136 5224.546 090
28.349 52331.103 476 8
0.453 592 37907.184 74
0.907 184 741016.046 908 8
1.016 046 908 8
CONCENTRATION0.029 166 6
0.583 333 33
ounce (troy)/ ton (short) pennyweights/ ton (short)
l ounce (troy)/ ton (short) l pennyweight/ ton (short)
34.285 714 2
1.714 285 7
OTHER USEFUL CONVERSION FACTORS
l ounce (troy) per ton (short) l pennyweight per ton (short)
Multiplied by 20.0 0.05
gg
kgkg
tkg
t
g't
pennyweights per ton (short) ounces (troy) per ton (short)
Note: Conversion factors which are in bold type are exact. The conversion factors have been taken from or have been derived from factors given in the Metric Practice Guide for the Canadian Mining and 'Metallurgical Indus tries, published by the Mining Association of Canada in co-operation with the Coal Association of Canada.
221
sKMfe3T-.
EP?
393
I .' -J "J 10 M HI'
l '7.
18V iir
jr.".' - y**.
"
it'
— :5V -Vk**.
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