1
Dear members, and friends of the LPS, Our final One Day Seminar for the year will be held on 14th December, with the title ‘Everything Formation Testing’. We have a remarkable agenda lined up for next Thursday (see page 2), so this is definitely not one to miss! Registration forms have already been distributed, and are also available on our website. Following this Seminar will be our annual ‘President’s Evening’ at the King’s Head, kindly sponsored by Gaia, Schlumberger, and Baker Hughes. This is a free event with drinks and finger food provided, and partners are most welcome to join us for the Christmas cheer. See the official invitation on page 3. This month’s technical article is ‘Rock Typing in Carbonate Reservoirs’, authored by Jonathan Hall who has previously held the office of VP Technology in LPS (twice). It is an informative and authoritative work, starting on page 7. Thankyou to all who attended our Annual General Meeting on 21st November, and also to those who had mailed in their postal ballot to successfully update Article 13 in our Constitution. As we presented, our income from both One Day Seminars & Sponsorship has fallen significantly. So we have introduced a range of measures to stabilize our financial situation, among these are cancellation of the free New Technology seminar in January, and relocation of Evening meetings to the smaller ‘Council Room’ in the Geological Society. In addition I anticipate that income from the 2018 SPWLA Annual Symposium will replenish the coffers. I would like to thank out-going Executive Committee members Carole Reynaud and Negah Arjmandpour for their efforts. Next year we introduce Shyam Ramaswami as Officer of Sponsorship, and welcome back incoming President Mike Millar. Mike first joined the LPS in 2005, and was President in 2012/13, so I am confident of leaving the leadership of our Society in good hands. Thankyou for the journey over the last two years, and I wish you the best in our fascinating pursuit of both the scientific and technical aspects of formation evaluation. Best Regards,
Michael O’Keefe
Michael O’Keefe - LPS President
London Petrophysical Society: Newsletter 2017-12 1 www.lps.org.uk
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Thursday 14th
Dec 2017
9:00 am –5:00pm
Tuesday 6th Feb
2018
6:30pm-730pm
Holger Thern,
Baker Hughes
Everything
Formation Testing
Thursday 14th December 2017
The Geological Society, Burlington House,
London
£150 for delegates (Speakers exempt)
(LPS is not VAT registered) Students can register for free
Includes lunch and post-seminar wine and savouries. Doors open at 9am.
For more info or to register for this event please visit www.lps.org.uk/events/
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The London Petrophysical Society
Cordially invites you to our annual
“Presidents Evening”
Thurs 14th December 5:30pm
Members & Guests are welcome!
The Kings Head
10 Stafford Street, Mayfair, W1S 4RX
(5 mins walk from the Geological Society)
Please note that we have reserved the
room downstairs exclusively for us.
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Thursday 14th Dec
2017
9:00 am –5:00pm
Tuesday 6th Feb
2018
6:30pm-730pm
Holger Thern, Baker
Hughes
“Integrated Gas and Oil Zone Evaluation using
NMR, Conventional, and Mud Gas Logging Data – A Norwegian Logging-While-Drilling Case
History”
Presented by
Holger Thern, Baker Hughes
Tues 6th February 2018 6:30pm—730pm
The Geological Society, Burlington House, Piccadilly
Refreshments will be available from 6pm.
Wine & Savouries will be provided after the presentation,
which we would be delighted for you to join us for.
- Free Entry -
Full Abstract and bio available online at
http://lps.org.uk/events/integrated-gas-and-oil-
zone-evaluation-using-nmr-conventional-and-
mud-gas-logging-data-a-norwegian-logging-while-
drilling-case-history/
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The LPS would like to extend a big thankyou to our departing President
Michael O’Keefe, and to the departing committee members Carole Reynaud & Negah Arjmandpour.
In 2018 we welcome Mike Millar and Shyam Ramaswami to the committee.
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Tuesday 21st Nov
2017
6:30pm-730pm
”
Prof Ruth Morgan
UCL
Thursday 14th
Dec 2017
9:00 am –5:00pm
The benefits of participating in the industry’s largest
gathering of Petrophysicists and Formation Evaluation
Specialists include:
• Exposure to a large local, national and international
audience of decision makers
• Opportunities to raise your company’s profile
amongst a valuable target audience
• Recognition of your organization’s demonstrated
involvement, commitment and support of the
industry
• Opportunities for your staff to exchange ideas and
discuss constantly evolving technologies with their
professional peers
• Valuable insights, information and exposure to the
latest technical and marketing developments, in the
presentations and posters, and in the Exhibits Hall
Check out our website for a full list of Symposium sponsorship opportunities or contact;
Dr. Kate Hatfield, Sponsorship Committee Chair
www.SPWLA2018.com
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Introduction
Petrophysical analysis by simultaneous
solution of logging response equations was
introduced over 30 years ago (Mayer and Sibbit). The logging response equations
embedded within the solution computation
follow similar forms to those previously
used in stepwise, so-called ‘deterministic’
workflows; viz. solving simple linear mixing
laws, for the most part, for ease of inversion.
where, Lbulk = tool measurement response to bulk rock and
fluids LMINi = tool measurement response to 100% ith mineral
LFLUIDj= tool measurement response to 100% jth fluid fMINi = the fractional volume of mineral i fFLUIDj = the fractional volume of fluid j
However, we observe that some
measurement-porosity relationships follow
a non-linear path in carbonate pore types. In the case of elastic moduli, measured or
derived from acoustic logs, the moduli-
porosity relationship, lies between the
Reuss and the modified Voigt boundary (see
below), influenced by the presence of
specific microstructures. Other more
rigorous bounds, such as Hashin-Shtrikman narrow these and a modified
upper Voigt bound may be necessary for
porous media above the Nur critical
porosity, fc, above which the composite
stops being a framework and becomes a suspension.
The implication of this is, that for a given
modulus measurement, porosity cannot be
accurately determined, using conventional
linear response equations, without knowledge of the microstructure of the
composite; its rock type, in effect.
Porosity could, however, be inferred to lie
between these or other rigorous bounds. However, if an accurate mixing law is
developed and rock type identified, then
porosity can be determined, or, conversely,
if effective porosity is, independently,
known then the rock fabric may be
inferred. For a single measurement this argument may become circular, but with
the addition of multiple logging tool
measurements, each with their own mixing
laws established, unique indications of rock type, could be extracted directly from bulk
log measurements. Corroboration provided
from visual observation on core, cuttings or
image logs provides additional constraint.
Current and future research and software development for characterisation of
carbonates will, likely, exploit simultaneous
non-linear global inversion of multiple
logging measurements, using more
advanced mixing laws, bounds and cross-correlations constrained by observations in
core, cuttings and image logs. We may have
to employ machine learning applications for
initial microstructure selection prior to
model testing.
The parameters this will yield, will go far
beyond volume fraction information: matrix
and fluid elements, and could yield much
more important insights about rock fabric
and pore structure: storage capacity and related flow capacity. Porosity evolution
and diagenesis products, that describe rock
fabric within a stratigraphic framework
could be unlocked.
Rock Typing in Carbonates: Traditional Approaches
Rock typing schemes for carbonates have been developed for over half a century and
were initially based upon description in
hand or thin section of grain size (Archie,
Dunham), observed pore size (various) and
linkage to permeability (Lucia, Lonoy). Ed Clerke looked at the importance of pore
throat size. Some rock typing schema
recognise post deposition diagenetic
changes to original fabric.
Some carbonate rock typing schemes commonly cited.
i j
FLUIDFLUIDjMINMINbulk iiiff
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Jonathan Hall ([email protected])
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Tuesday 21st Nov
2017
6:30pm-730pm
”
Prof Ruth Morgan
UCL
Thursday 14th
Dec 2017
9:00 am –5:00pm
Yet for all this, the standard static model
build for a carbonate reservoir follows a
conventional workflow based upon observation and description of recovered
core/drill cuttings or outcrop analogues, or
to a lesser degree image logs, to establish
depositional or diagenetic facies and facies associations. Subsequent to this,
multivariate statistical techniques and log
measurements are used proxy to infer the presence of a particular prior-observed rock
type. Thereafter, or indeed as part of the
rock type recognition process, petrophysical
properties, in particular, seismic and
geomechanical properties, storage and flow capacity are calculated; these being the
important determinants of a successful
exploration or field development project.
The purpose of rock typing, then, is to use
log measurements as proxies to direct observation and has two elements;
• To fill in the gaps, intra-well, between
textures and reservoir quality indicators
observed in cored intervals to un-cored
intervals, using log signatures, and to
establish vertical baffles and barriers to
flow/migration based upon stratigraphic and structural
observations and inferences;
• To infer inter-well, spatial and temporal
distribution of reservoir storage
capacity, baffles and barriers to flow,
and seals using geostatistical or, more
recently, deterministic models.
Poor Correlation Between
Mineralogy and Rock Type
The first difficulty that carbonates present
in achieving this, is that important
differences in rock texture that give rise to
variability in storage capacity and deliverability do not necessarily correspond
to observed variations in mineralogy.
Indeed, the mineralogy of a mud dominated
limestone, when compared to that of a
grain dominated limestone, using the Dunham (1962) classification, in a
carbonate platform depositional setting,
may exhibit negligible mineral variation.
Here, there is little marine influenced clay
content or wind blown fine grained clastic, allochthonous (externally derived),
material. In this context, the main observed
components are:
• carbonate grains comprising aragonite, high- or low Mg calcite);
• lime mud/micrite;
• calcite spar cement or , fibrous calcite.
As a consequence of this poor mineral
contrast, successful differentiation between
rock types, may be a problematic exercise, particularly when using legacy density,
neutron and gamma ray log signatures.
Gamma Ray log amplitude variation may be
slight and density and neutron processing
historically yielded a total porosity and little
more in this setting. I will address acoustic logs and resistivity logs in the context of
pore connectivity and transport
phenomena, shortly.
This lack of mineral contrast obfuscating rock texture is not confined to limestone
carbonate platform settings. In 2010, Hall
et al showed that two distinct generations
of dolomite formation had occurred with
vey distinct storage and flow capacity
characteristics.
The Triassic Kurrachine Dolomite
Formation at the Ash Shaer Field,
comprises repeated sequences of
mudrocks, dolomitised carbonate mudstone and wackestone, peritidal
limestones, subaqueous anhydrite and
halite. These were deposited in a restricted
basin that was intermittently connected to
the Neo-Tethys Ocean.
Repeated sequences of mudrocks, dolomitised carbonate mudstone and wackestone, peritidal limestones, subaqueous anhydrite and halite in the
Kurrachine, Ash Shaer Field.
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Almost all of the observed porosity in the
Kurrachine Dolomite is secondary porosity.
Early dolomitisation processes occurred at shallow depth by seepage of saline brines
associated with evaporite deposition. Burial
dolomitisation processes, such as
displacive dolomite veining, created
euhedral crystal-lined porous and
permeable 'zebra structures’ and dolomite breccias. Results of fluid inclusion studies
suggested that the timing of reservoir
hydrocarbons’ charge was after the late-
stage burial dolomitisation and involves
high temperature hydrothermal fluids.
Zebra fabric ‘rhythmites’ in Middle Kurrachine cored interval.
More textural information may be obtained
from borehole image logs, vertical
interference pressure testing, chemical
tracers and an interesting cased hole log application log, spectral noise logging,
yielding information about connectivity at
hydraulic unit scale and higher; being well-
suited to static and dynamic model builds.
Nuclear magnetic resonance logs, in continuous mode acquisition, may yield a
pore size distribution and, if T2 distribution
can be reliably set, and significant a priori knowledge is available, an irreducible water
saturation, Swir, value may be determined.
Both of these parameters may be useful
indicators in determining storage capacity,
but may yield ambiguous interpretation as
to connectivity or flow capacity unless, they can be independently, calibrated. NMR
offers pore size distribution functions to be
developed.
Pore size distribution modelling from an Aptian platform limestone, Abu Dhabi, SPE165150 2013
Other microstructure correlation functions
can be developed for n-dimensional two phase isotropic media and include: • n-point probability functions
• surface correlation functions • lineal-path function • chord-length density function • pore-size distribution functions • percolation and cluster functions
The Influence of Carbonate Microstructures Many carbonates exhibit random
heterogeneous structure, yet at microscopic
scale may demonstrate some isotropic
repeating structures. The field of study that
unifies, rigorously, both microstructures
and their macroscopic properties has been studied for many natural; biological,
geological and synthetic porous
heterogeneous materials (Torquato 2002).
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Jonathan Hall ([email protected])
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”
Prof Ruth Morgan
UCL
Thursday 14th
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9:00 am –5:00pm
Some examples of specific microstructures
with repeating fabric can be found within
the rock type schema suggested above and include:
• intra crystal microfractures
• micrite
• ‘non-touching’ vugs
• ‘touching’ vugs
• fenestral porosity
• ooids and peloids
Four carbonate microstructures: Top, microfractures (Kuwait), 2nd, ooids (Arenque
Mexico), 3rd, non-touching vugs and touching
vugs (both Kuwait), 30X magnification.
Whilst acoustic logging was introduced, in
part, to serve the needs for velocity versus
depth for seismic calibration and for
interpretation of stratigraphy in geophysical
studies, in petrophysics it was seen as
another porosity tool. The inadequacy of the Wyllie-time average model at higher
porosities became evident and the Raymer-
Hunt transform introduced a term to
account for consolidation of the sediments.
The poverty of the Wyllie Time-average equation. The representation of the porous medium
in the Wyllie transform treats the solid and
fluid phases as separate and any
interactions between them are ignored. The
rock is represented as having no pores, so
that concepts of acoustic tortuosity, permeability of pores giving rise to “squirt”
and fluid viscosity are not incorporated.
In 1971, Nur demonstrated the effects of
stress on velocity in porous rock with cracks. Anselmetti and Eberli (1993, 1999,
2012) demonstrated how carbonate
microstructures affect compressional
velocity and that for many carbonate
fabrics the Wyllie time-average equation
underestimate velocity. Baechle et al (SPWLA 2008) suggest that understanding
of this may allow inversion of acoustic or
seismic data to reveal the specific
microstructure giving rise to it.
Pore shape affects acoustic velocity, Modified after Anselmetti and Eberli, 1993,1997.
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Wang and Nur (1992) note the Wyllie
should not be used in the following
settings:
• Low velocity fluids (gas);
• Fractured rocks: where Vp is lower than
Wyllie predicts
• Rocks with isolated (non-connected
pores): vugular, moldic or fenestral
pores as Vp is higher than Wyllie
predicts;
• Soft and Unconsolidated rocks
Hall and Alvarez (2010) introduced a mixing law based upon an observed trend
between the derived value of the Biot poro-
elastic term, designated a here, and
porosity for a range of carbonate rocks,
principally from France (Bouteca et al 1991
& Laurent et al 1993). In their work they demonstrated that the mixing law
adequately captured variations in bulk
modulus resulting from clastic sorting,
which modifies critical porosity, (Nur et al
1995), which is expressed in the mixing law. It also adequately captures variations
in matrix and fluid bulk modulus arising
from variable mineral matrix and fluid
saturations but no attempt was made, at
the time, to characterise particular
microstructures. The use of this Biot related term and the expression of a further
fitting term, “a”, in their formulation would
allow fitting of data to measurements with
characteristic microstructures. The authors
have found that critical porosity has a maximum of about 43% for clastic (rhombic
packing) but for carbonates which
consolidate from chemical precipitates,
higher critical porosities in the region 50-
58% are necessary. With these fitting terms
the authors have been able to test whether it is possible to identify micro-textural type
and thereby, in context microfacies from
elastic and acoustic measurements.
Meff, is the effective compressional elastic
moduli (K, l or M) and MVoigt and MReuss are,
Voigt and Reuss averages of the elastic
moduli computed all minerals and fluids
and the value of the empirical constant, where:
“a” is generally around 4 for granular rock (erratum, and not 0.25 as originally
suggested in the 2010 publication due to a
late reformulation error). This is now
reformulated as follows as this makes for a
more theoretical justification that will be published early next year, rather than, at
most, a heuristic one, which was
demonstrated in their 2014 SPWLA paper.
In the cross plot bulk modulus-porosity
carbonate examples above, data sets of
formation factor, permeability, porosity and
acoustic velocity and CEC, are published
for micritic microporosity limestone from Regnet et al, 2015, and porous limestones
and dolomites displaying interparticle and
skeletal grainstone, floatstone, oolites often
displaying vuggy and moldic porosity from
Maria-Sube, PhD Thesis, 2007. Note that
the microporous rocks are best fitted with a lower, Alvarez-Hall, ’a’, value for the mixing
term, than for the higher Bulk Modulus
dominantly dissolution micro-structures in
the Maria-Sube data set. This shows that
their model can formalise the observations of Anselmetti and Eberli and be used to
rock type certain carbonate
microstructures.
12
Jonathan Hall ([email protected])
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2017
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”
Prof Ruth Morgan
UCL
Thursday 14th
Dec 2017
9:00 am –5:00pm
Macroscopic Effective Properties: Tortuosity Again
An illustration of the realities of these
physical bounds comes from work
published by Herrick and Kennedy (1996).
These authors measured resistivity index
on two composite core plugs comprising, in
one case, a parallel arrangement of three isotropic materials and, in the other case, a
series arrangement. The figure below
reflects their measurements. In electrical
transport property terms we used the
characteristic length concept, tortuosity, to
define the conductivity path of 100% brine saturated composite medium through the
Archie ‘m” term and another modifier,
Archie ‘n’ term desaturated (drainage) or
resaturated (imbibition) cycles.
Results of resistivity index measurements made by
Herrick and Kennedy, 1996, on series and parallel arrangements of matrix material with different formation factor values
Four classes of steady-state effective media problems, modified after Torquato, (2002) and pers. comm. (2017).
Tortuosity as a term used by
petrophysicists, reservoir engineers or
geologists is often used to describe transport processes in a composite porous
material. Values for electrical, diffusional
and hydraulic tortuosity differ. Electrical
tortuosity is defined in terms of
conductivity whereas hydraulic tortuosity is
usually defined geometrically, and diffusional tortuosity is derived from
temporal changes in concentration.
Tortuosity might be better defined in terms
of the underlying flux of material or
electrical current with respect to the forces, which drive this flow.
Torquato, (2002) recognizes 4 classes of
steady state effective media problems,
where and we recognise that most are commonly study in certain oilfield
applications.
In the figure above, modified after Torquato, 2002. Left: L and l represent the macroscopic and
microscopic length scales. Right When L is bigger than l, the heterogeneous material can be treated as a homogeneous material with effective property, Ke •
It is this characteristic length that defines tortuosity, which underpins the rigorous
relationships between transport processes
in rocks. In this way, for carbonates, the
macroscopic measurement of various
effective properties can be related specific microstructures, and thereby to rock type
Impact on some macroscopic transport
properties of certain microstructures.
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Cross Property Correlations
M. Kachanov et al (2000) posed an
intriguing fundamental, as well as
practical, question concerning anisotropic
porous materials. Can different effective properties be explicitly linked to one
another? Such cross-property correlations
become especially important for applications if one property, say, electric
conductivity, is more easily measured than
another property, such as a full set of
anisotropic elastic constants, or vice versa.
The effective property in one domain, with a
specific set of governing equations as
indicated in the modified Torquato table
above, can be either rigorously linked to
one another, or, as in the case suggested
above, defined by a specific fabric, the effective properties of another domain
might be discerned. If this is not exact then
the bounds of one effective property might
be applied to another effective property
For reader reference, other sources for
cross property correlation work, in the
published literature, include the following:
Milton (1984) describes an arbitrary d-
dimensional isotropic two-phase media,
wherein, if the phase bulk moduli, K, equal
the phase conductivities, se, then the effective Bulk Modulus, Ke, is bounded
above by the effective conductivity, se.
Torquato generalised this and showed that:
where neither of the isotropic media has negative
Poisson’s Ratio and Ke/K1 and e/1 are dimensionless effective bulk modulus and effective dimensionless conductivity, respectively
Torquato (1992) relates the dimensionless
effective shear modulus Ge/K1 to an effective
dimensionless conductivity, respectively, again where neither phase has non-
negative Poisson’s ratio, :
An interesting example of the practical
application of such cross property correlations in the petrophysics craft is the
prediction of the macroscopic property: the
Archie cementation exponent, ‘m’, as a
continuous or discrete variable, from elastic
properties measured on logs.
The practical difficulties in establishing this
property through an inversion of Archie’s second law are that the objective of the
study water saturation, Sw, must be known,
a priori, or assumed; and this necessitates
some knowledge of another drainage/
imbibition phase dependent variable: the
Archie’s saturation exponent, ‘n’.
Identification of specific microstructures using Lame parameters which can be manipulated using the Torquato cross property correlations
Downton, Dewer et al (2000) established
relationships between the Lame parameters
and lithology to predict porosity from
seismic, P and S wave. From the same
crossplots in log domain, regions of fractures and framework porosity types
were defined above. Connected vug porosity
types are seen to fall between these regions
as observed in image logs, core and thin
section.
The approach adopted, in this illustration,
is to use Lame parameters to identify zones
of similar elastic compliance: vugs,
fractures, interparticle porosity, calculate
14
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”
Prof Ruth Morgan
UCL
Thursday 14th
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fracture, vuggy or moldic porosity and
apply the triple porosity model for a
carbonate developed by Ali Ghamdi of Saudi Aramco, Prof. Roberto Aguilera
(University of Calgary), SPE-132879-PA,
and their collaborators. Their model relates
connected matrix porosity to fractures, and
non-connected porosity types: vugs,
intragranular, moldic, or fenestral porosity, and via the volumetric fractions of each, to
establish the electrical tortuosity,
equivalent to the macroscopic petrophysical
Archie parameter, the cementation
exponent.
The inputs required are:
• fracture porosity, which still requires
some further work to establish a truly
effective aperture width from which we
determine accurate fracture porosity
from images;
• the proportion of so-called “secondary
porosity”; an inadequate term used in
the petrophysics craft, to indicate both
fracture and non-connected porosity
fractions but in this model to establish
the non-connected fraction of the total
porosity;
• and the remaining inter-granular/
intra-granular fractions.
In the future this could be solved by an
inversion rather than this stepwise
approach.
Dr. Mohammed Watfa (1987) describes, a
macro-scopic solution, through “tube
bundles”, whereby, the number of tubes
(porosity), brine salinity and the combined
length of the ‘tube bundles’ define the macroscopic property, ‘m’ in a
combinatorial manner. His work describes
a thought experiment of a single tube and
the electrical conductivity of adding a
parallel equivalent tube of equal porosity and an equivalent extra porous
contributions from a vug placed wholly
within the original ‘tube’. This was based in
part upon studies described by Focke and
Munn on moldic limestones in Qatar
(SPE13735) which indicated cementation values of m>5.0.
Concluding Remarks
Rock typing of carbonates is an inadequate
predictive tool in subsurface geo-modelling
and flow simulation; suffering, still from a
traditional ‘bias’ towards depositional facies description and that this is enough to
represent the distribution of reservoir
properties (Skalinski and Kenter 2014).
The number of carbonate microstructures now studied is growing and their impact on
certain logging tool combinations being
understood. As a corollary, we can now
identify and quantify petrophysical
properties and rock fabric beyond just the
volumes of their constituents directly from their response on specific individual log
responses.
Current and future research and software
development for characterisation of carbonate reservoirs will, likely, exploit
simultaneous non-linear global inversion of
multiple logging measurements using more
advanced and calibrated mixing laws,
constrained by observations in core,
cuttings and image logs and employ machine learning applications for
microstructure selection. The parameters
this will yield will go far volume fraction
information: matrix and fluid elements, and
could yield much more important insights about rock fabric and pore structure:
storage capacity and related flow capacity,
porosity evolution and diagenesis products,
as well as describing juxtaposition of rock
fabrics within a stratigraphic framework.
Recent personal communication with
Professor Salvatore Torquato of Princeton
University confirms that many of the
microstructures can be described,
mathematically, and that 3-D printing techniques could be used to test effective
properties of these and initiate machine
learning techniques.
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Acknowledgements
I am grateful for the previous collaborations
that have brought me to the observations
above. In particular: Dr. Pete Gutteridge, Dr. Benoit Vincent, both of Cambridge
Carbonates Limited, Dr. Erick Alvarez, now
of Shell, Norway and Raghu Ramamoorthy
of Schlumberger for many interesting
collaborations in Abu Dhabi.
The Author
Jonathan Hall is an independent
petrophysicist and was for five years
Petrophysics Expert at the Abu Dhabi
Company for Onshore Oil Operations,
ADCO. Jonathan has worked as staff and consultant petrophysicist in/to British
Petroleum, British Gas, Agip International,
Pemex, Schlumberger, Qatar Petroleum,
Suncor (formerly Petro-Canada) and Dong
Energy E&P. He has also held the position of Head of Petrophysics for Scott Pickford
(then a Core Laboratories company) and
Senergy. Jonathan graduated in Geology
from the University of London, Kings
College and studied Mineral Exploration at
the Royal School of Mines, Imperial College.
16
The LPS wish to extend our sincere appreciation to the
generous companies who continue to be our Sponsors.
Sponsor Corporate links (in alphabetical order) are:
• Baker Hughes www.bhge.com
• BP www.bp.com
• Gaia Earth Sciences www.gaia-earth.co.uk
• GE Oil and Gas www.geoilandgas.com
• Halliburton www.halliburton.com
• Nexen www.nexencnoocltd.com
• Oilfield Production Consultants (OPC) www.opc.co.uk
• Schlumberger www.slb.com
• Shell www.shell.com
• Tullow Oil PLC www.tullowoil.com
• Weatherford Laboratories www.labs.weatherford.com
17 London Petrophysical Society: Newsletter 2017-12 www.lps.org.uk
Thursday 14th
Dec 2017
9:00 am –5:00pm
Tuesday 6th Feb
2018
6:30pm-730pm
Holger Thern,
Baker Hughes