Mesa Training Manual

7/21/2019 Mesa Training Manual

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This series of exercises will introduce you to many of theoptions that are available in MESA for the design and QC of3 surveys! "t is a good idea to refer to the MESA user#s

manual for more details about the features described in theseexercises!

• $rogram $urpose!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! %

• &M& atabase 'iles!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!%

• Steps in Survey esign!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!(

• )and 3 Seismic Survey Classifications!!!!!!!!!!!!!!!! !!*

• &eometry Examples!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!+

• Seismic ata $rocessing "ssues!!!!!!!!!!!!!!!!!!!!!!!!!!!!,3• "nformation &athering!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!,*

• E-uations .sed in Survey esign!!!!!!!!!!!!!!!!!!!!!!!!!!,+

• Survey Analysis and QC!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!%/

• Shooting Techni-ues Compared!!!!!!!!!!!!!!!!!!!!!!!!!! !!%0

• Ex 1,2 asic MESA .sage!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!%4

• Ex 1%2 )ine5ric6 )ayout 7ptions !!!!!!!!!!!!!!!!!!!!!!!!!(%

• Ex 132 .nit Template )ayout!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!0,

• Ex 1(2 The esign &uide!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!0*

• Ex 102 "mporting Survey 'iles!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!*3

• Ex 1*2 Marine esign!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*8

• Ex 1+2 .sing &M& "mage!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!+(

• Ex 182 Source and 9eceiver Editing!!!!!!!!!!!!!!!!!!!!!!++

• Ex 142 7ffset and 9ectangular Shooting!!!!!!!!!! !!!!!8%

• Ex 1,/2 Automatic Template Centering!!!!!!!!!!!!!! !!!8*

• Ex 1,,2 Salvo Shooting!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!4,

• Ex 1,%2 )abel Shooting!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!43

• Ex 1,32 Multi:Survey Capability!!!!!!!!!!!!!!!!!!!!!!!!!!!!!4+

• Ex 1,(2 .sing Advisor!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!,/3

• Ex 1,02 Attributes and 'iltering!!!!!!!!!!!!!!!!!!!!!!!!!!!!,/*

• Ex 1,*2 isplaying ata!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!,,*

MESA Training



Program Purpose

MESA provides a great deal of flexibility in 3 survey design and analysis; whether the survey is

a land; transitional area; ocean bottom cable; or marine design! "magery; contour information;

and cultural features <provided from !dxf files; for example= can be used as bac6grounds to aid in

the design of the survey! "n this way; permit and logistical problems can be anticipated at the

planning stage; reducing the time and cost of field ac-uisition!

esides flexibility in design methods; MESA provides flexibility in shooting methods and bin

attribute analysis! Additionally; a number of output file formats are supported; including SE&$:,;

.>77A; and S$S; in addition to shooting scripts for "nput57utput and A9AM ac-uisition systems!

The completion of a survey design in MESA generates a &reen Mountain &eophysics &eoScribe

geometry database; thereby completing a ma?or portion of the initial pre:stac6 processing wor6

while still in the field! These database files are transportable across various hardware platforms;

ma6ing MESA a practical tool for field and office environments!

GMG Files and the Database

The following set of files represents what &reen Mountain &eophysics refers to as the MESA or

&eoScribe database! These files are a combination of ASC"" and binary files and combine to

hold all of the information needed to define the geometry <and refraction statics= for any % or 3

survey! @ot all of these files will be found with every database! The !bin and !mid files are

re-uired only for bin attribute displays and can be deleted before archiving the database; if

necessary!

File Extension Format Description

!atr inary Attribute information for receivers

!ats inary Attribute information for sources

!bin inary in information; siBes

!bmp inary $icture for open database preview display

!cf, ASC"" Configuration file for the receiver spreadsheet

!cf% ASC"" Configuration file for the source spreadsheet

!def ASC"" efault values for MESA to use with this survey

!fbt inary ''" info and first brea6 pic6s

!hdr ASC"" eader information for S$S outputs

!idd inary "mage ray attribute information

!inr ASC"" "nstrument information for receivers

!ins ASC"" "nstrument information for sources

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!lbs ASC"" )abel shooting information

!mar inary Marine survey information

!mas ASC"" atabase parameters and status flags

!mdd inary Model attribute information

!mdl ASC"" Aperture model information

!mid inary Midpoint information; offsets; aBimuths

!mrl inary Streamer marine receiver locations

!mut ASC"" Mute function information

!ndd inary @ormal ray attribute information

!pat inary Source5receiver template relationships

!rdd inary 7ffset ray attribute information

!rfi ASC"" 'ilter settings for receivers

!rln ASC"" )ine names for receivers

!se- ASC"" &eneral shooting se-uence description

!sfi ASC"" 'ilter settings for sources

!sln ASC"" )ine names for sources

!sor inary Source numbers and coordinates

!sta inary 9eceiver numbers and coordinates

!tpl inary Source to receiver patch relationship

!unt ASC"" Configuration of the unit template

!xcl ASC"" Exclusion Bone type; siBe; and all coordinates

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Other GMG Files used or created in MESA

File Extension Format Description

!cfg ASC"" Configuration file used to import survey files

!csi ASC"" Color scale settings

!cyr inary &M& contour file

!lyr inary &M& image file

!nop ASC"" MESA midpoint exclusion output file

!ptn ASC"" MESA pattern output file

!scr either "nput57utput script file

!sts ASC"" MESA land statistics5cost output file

!tdf ASC"" Trace data format file used to import SE&D files

!vyr inary &M& vector file

4



Steps in Survey Design

Step 1 !uilding an "ideali#ed$ survey

MESA provides several methods for defining a survey!

1% Direct layout and shooting .sing the source and receiver layout dialogs; you can create

orthogonal <bric6 or straight line=; Big:Bag; slash; button patch; and radial surveys! The

surveys are created by specifying information such as inline and crossline spacings;

bearings; and survey siBe! Several shooting options are then available to define the source:

receiver template relationship!

&% 'nit (emplate Dou can create a unit template; a group of sources which are fired into a

common receiver template; in the .nit Template window in MESA! This unit template is then

repeated throughout the design area to simultaneously define and shoot the survey! The unit

template is good for creating bric6; orthogonal; button or swath surveys!

)% *mporting AS+** ,iles ASC"" files containing coordinates and source or receiver numbers

can be imported directly into MESA! Examples of these files are .>77A; SE&:$,; and S$S!

"f ASC"" relational files or ASC"" or binary shooting scripts are also available; they can be

imported; as well!

Step & +reating a "real -orld$ survey

7nce the initial design parameters have been set for the survey; aerial and satellite imagery;

scanned topographic maps; contour displays; and5or files containing cultural information <!dxf

files; for example= can be used to modify the design to ta6e into account physical and culturalobstacles!

Exclusion Bones which exclude sources; receivers; and5or midpoint information can be defined ascircular; linear; or polygonal Bones! These Bones can be defined graphically; by manually enteringcoordinates; or by importing coordinates from an ASC"" file! 7nce the exclusion Bones have beendefined; the survey can be designed around them!

Editing functions allow the user to selectively deactivate sources and receivers as well as relocatethem in groups or individually using the mouse or 6eyboard! The redesign a line function allows thesource or receiver lines to be re:drawn maintaining the inline group interval and thus preserving thestac6 response : extra receivers may then be re-uired to fill the gap! A snap to grid function mayalso be used to ensure that source and receiver moves maintain the group interval! Thus; the survey

is as close as possible to the real world conditions before any e-uipment is deployed; minimiBing thetime in the field for e-uipment and crew!

5



Step ) 'pdating -ith surveyed coordinates

The theoretical survey design can easily be updated with actual coordinates from the survey crew

on a shot by shot; swath by swath; or daily basis through the ASC"" file import option! The new

coordinate information may be provided as absolute values or shifts from the original position!

Analysis of the ongoing ac-uisition; via the bin attribute displays; allows for the repositioning

and5or addition of sources and receivers in order to compensate for any deficiencies which mayhave appeared in the desired fold; offset; or aBimuth distributions because of conditions in the

field!

6



.and )/D Seismic Survey +lassi,ications

Jim Musser, Director GMG Energy Services

(ype Applicable Areas Advantages Disadvantages

"n:)ine Swath 7pen Terrain @arrow aBimuth data can beprocessed and analyBed li6e %:seismic

$oor cross line statics; highS9C and 9CF line density;very sensitive to obstructions

7rthogonal All Terrains Gide aBimuth; good for 3: M7;can solve cross line statics;industry standard; economicoperations

Must use 3: algorithms;cannot use simple % ':>algorithms

ric6 7pen Terrain )i6e orthogonal; plus improvesnear offset and overall offset

distributions

iscontinuous source linesare difficult in ?ungle and in

some other terrains

Slant All Terrains "mproves overall offset coverage;better offsets for AF7

Surveying and line clearingon source lines are longerdue to diagonal lineorientation

utton $atch 7pen Terrains;'arm )and; Arctic;esert

Allows sparser source points;efficient use of large channelsystems

Complex to plan

Fariable )ineSpacing

All Terrains Modification of orthogonal; bric6; or slant design with similaradvantages to each; plusguarantees surface consistency

Complex to plan

Asymmetric Spread All Terrains Modification to orthogonal; bric6; or slant design with similaradvantages to each; plus longeroffset with less recordinge-uipment

Same as for orthogonal;bric6; and slant designs

9andom All Terrains Surface consistent; minimiBesac-uisition footprint

Complex to plan and operate

7



Geometry Examples

Any of the following geometries can be built in MESA by using the unit template option or by directlyplacing the sources and receivers before shooting! 'or each geometry; there is a view of the .nitTemplate window followed by a view of the esign window; as well as the main points for and against

each survey type!

8



*nline S-ath shooting / Marine li0e

$ros2 Simplest geometry for 'SF type recording systems!Cons2 $oor aBimuth distribution; poor coupling; high fold!

9



Orthogonal or straight line shooting

$ros2 Fery simple geometry to lay out in the field!Cons2 Comparatively expensive and yields largest Hmin! 9e-uires good access for

sources and receivers!

10



!ric0 shooting

$ros2 Smaller Hmin reasonable aBimuth and offset distribution with potential for statics coupling!

Cons2 9e-uires good access for both sources and receivers so not suited to areas withaccess problems! Excessive long offsets may result with whole survey; orreplanting of geophones!

!utton Patches

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$ros2 Efficient utiliBation of large channel systems with minimum source access and effort!Cons2 Can re-uire large numbers of sources! 9e-uires computeriBed planning! CM$

fold does not yield same offset5aBimuth distributions in ad?acent bins!

ig#ag <including mirrored; double; triple and shifted double BigBag=

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$ros2 Smaller Hmin with good offset and aBimuth distribution!Cons2 7nly good in conditions of open access such as deserts!

13



Seismic Data Processing *ssues 2elated to Geometry

Migration

Migration creates some profound re-uirements on survey design! iffracted events in the

subsurface impose the re-uirement to sample more time and wider areas; in order to capture

enough of the diffraction to collapse its energy! This almost always will re-uire the design

geophysicist to record seismic data over an area which is much larger than the actual prospect

area! The calculation of this Imigration apertureJ is described in the E-uations section!

2e,raction Statics

"f you are designing a survey in an area where significant weathering and statics problems may

exist; you will want to focus some energy on optimiBing your survey to solve these problems!

Several refraction statics algorithms exist! Most of these algorithms are primarily numerical

e-uation solvers; which are dependent on statistical redundancy for the best solutions! Statics

coupling does not play a large role with most refraction statics algorithms because the statics are

not measured in the midpoint domain; and there is no structural or 9@M7 term to solve in the

standard e-uation!

Therefore; anything which improves the -uality of the first brea6s will contribute to enhanced

refraction statics solutions! A single point dynamite source with no significant receiver field arrays

will produce the best results! &eometries with receiver lines which are not straight produce first

brea6s which can be very difficult to pic6!

Statistical algorithms will perform best if the statistics provided are consistent and well sampled!

This would re-uire the designer to balance source point fold and receiver point fold! Dour finaldesign should produce source5receiver fold of * or more!

Split spread type shooting creates surveys which have reciprocal travel paths! Many types of

algorithms depend on reciprocal paths to build stable solutions! 7ff:end shooting schemes

should be considered as a last resort!

Shallow refractors will re-uire narrow receiver line spacing or they will not be well sampled!

2e,lection Statics

"t is our experience that most regular 3 designs will decouple in the traditional sense without

editing! Ghat saves the designer in most cases is the fact that sources and receivers are shifted

around in the field; providing a pseudo:randomiBed version of the original plan! Ghile this

randomiBation tends to have a coupling effect on the survey; it does not however guarantee that

the survey couples! The noise plot in MESA demonstrates the degree of coupling which a survey

design possesses!

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"f you understand any potential statics problems which may exist in the survey area; you can

consider the way in which your design will sample the statics problem! Extremely long

wavelength statics or large 6nown statics may affect the sampling decision made by the designer;

relating to crossline length or receiver template siBe!

3elocity

Many of the best 3 velocity algorithms are currently using aBimuth as well as other information

to build plots and aid in the determination of stac6ing velocities! These types of algorithms

re-uire that bins sample offsets and aBimuths with enough statistics so the data can be analyBed!

Felocity analysis is usually performed on a super bin; so users should be aware of how the bin:to:

bin relationships of offsets and aBimuths will complement each other! )arge gaps in offset

distributions or absence of near traces on shallow reflectors can contribute to problems in the

analysis!

Deconvolution

Surface consistent deconvolution presents the same re-uirements that reflection statics does!

Evenly sampled data in both the source and receiver domain will contribute to better solutions! At

far offsets; the data often becomes distorted by incidence angle and emergent effects; ma6ing far

offsets unusable for the derivation of the deconvolution operator! This imposes additional

re-uirements that the near traces need to be well sampled to provide the information re-uired by

the deconvolution algorithm!

DMO 4Dip Moveout5

M7 will function best if a survey is sampled at all offsets and all aBimuths! 7bviously; this is not

possible! Modern processing techni-ues can ma6e up for the lac6 of sampling re-uired; but a

well:sampled survey in both offsets and aBimuths will produce better solutions!

M7 is 6nown to create amplitude artifacts in 3 surveys! This amplitude effect is called

geometry imprinting; artifacts; or geometry Ifoot print!J The imprinting effect is reduced if a broad

range of aBimuths is collected! As has been demonstrated; this effect becomes more pronounced

for steeper dips and shallower targets <small reflection times=!

+oherent 6oise Attenuation

Much research has been done in recent years relating to attenuation of coherent noise with

ac-uisition geometry! The Ibleed throughJ effects of source:generated noise differ depending on

the ac-uisition design! Certain geometries will attenuate noise better than others will! )oo6ing at

this issue in a post:stac6 or post:migration environment is the current wor6 of researchers at

several ma?or companies! @oise plots and Array Analysis from the Advisor menu can be used to

perform source and5or receiver array noise analysis!

15



2elative Amplitude 4A3O7 A3A5

AF7 <amplitude versus offset= and AFA <amplitude versus aBimuth= analyses could be a part of

the processing flow in some data areas! &ood offset and aBimuth sampling within the useful

range of analysis is a strict re-uirement for either analysis!

Try to gain an understanding of the useful offset range to observe AF7 effects in the survey area!etails li6e this can help ma6e tough decisions about tradeoffs easier! The tough decisions refer

to compromises between the desired source or receiver sampling and the economic limits that

exist!

16



*n,ormation Gathering

ere are some issues to consider during survey design! This list is not exhaustive!

Exploration Ob8ectives

Type of feature <anticline; fault; reef; etc!=; Exploration method <structural; stratigraphic=; Stri6e;

ip; )ithology of target; and )ithology of overburden

(arget Description

epth; Arrival time; Average velocity to target; "nterval velocity at target; ip <expected;

maximum=; ed thic6ness; 9e-uired vertical resolution; esired reflection fre-uencies; ExpectedhoriBontal resolution; and Shallowest reflection

Operational +onsiderations

Expected noise <ambient; source:generated; non:random=; $ermitting5$ositioning; Timing

limitations 5 weather limitations; Access problems; igital maps or imagery available; and ata

processing

17



E9uations 'sed in Survey Design

!in Si#e

To avoid spatial aliasing in the data2

in siBe at subsurface Kα sin4 f

V i

where Fi L interval velocity at target

f L maximum expected fre-uency from target

α L dip angle

6ear O,,set 2ange

Hnear Fshallow x Tshallow

where / to Hnear is the offset range over which 3 fold or more is needed tostac6 the shallowest re-uire horiBon

Fshallow L Mute velocity in the shallowest section <often ,8// to%/// m5s=

Tshallow L Two way travel time to the shallowest re-uired horiBon

.ong O,,sets

Hlong L Fnmo t t t ∆+∆ *)0(*22

where Nt L t<x=nmo O t</= <use Nt /!% to /!3 seconds to estimate ade-uatemoveout for velocity analysis=

18



Spatial 2esolution

Minimum 3ertical 2esolution L Fi 5 < (!/ <Max 're- O Min 're-= =Maximum 3ertical 2esolution L Fi 5 < %!/ <Max 're- O Min 're-= =

where Fi L the interval velocity at the target

.ateral 2esolution L <3 x Fertical 9esolution= 5 sin <3/°=

Maximum dip is usually a value which is no less than 3/°! "f structural dips are

less than this; it is a conservative practice to use 3/°!

Fold +overage

"f previous % data exists for an area with good signal to noise ratio; a Irule ofthumbJ for 3 fold is to use between one:half to two:thirds of the % fold!

Source Density 4sources per s9uare 0ilometer5

Source ensity <@S= L P% <'old x ,/*= 5 <9 x x x y=

where 9 is the number of recorded channels

x is the inline bin dimension

y is the crossline bin dimension

6ote this e9uation re9uires that bin dimensions be in meters%

Source .ine Spacing

Source )ine Spacing L ,/* 5 <@S x min=

where min is the smallest bin dimension

@S is source density <sources per s-uare 6ilometer=

6ote this e9uation is true only i, the layout geometry is split spread%

19







"n the above example the labeling and internal numbering are consistent! "n this example thelabeling# is the user:defined */,8# and is an editable -uantity! The internal numbering for thisreceiver is the combination of the non:editable line index and the position in line! "t is important torecogniBe this when considering receiver5source deletion as this will have an effect on the shape andposition of the template! 7ften it is more convenient to turn off# <de:activate= a number of receiversrather than deleting# them <remove from the database= as turning them off will maintain the internalnumbering and thus will maintain the template shape!

After shooting is finished; a template can be viewed by either selecting Edit Templates from the.tilities menu or by holding down the Shift 6ey and )eft:Clic6ing on a source! The active receiversfor the template will be displayed with the I"n TemplateJ color!

'urther information on receivers and sources is accessed and edited through the appropriate editmodes or spreadsheets!

7ffset and 9ectangular shooting are the easiest methods for shooting a survey! "n either case; theonly thing that must be done is setting the offset ranges! All of the receivers that are within the offsetranges for a source are added to the template for that source! These methods of shooting are useful

in areas with irregular receiver geometry!

To use the other methods of shooting; a template must first be created! The template is defined byspecifying the number of receiver lines; number of receivers per line; and a starting receiver! Morecomplex templates can be created by using the Edit Templates option available in the Shootingdialog!

Automatic Template Centering is the most commonly used shooting method in MESA! 'or thismethod; the closest receiver to a source point is located and used as a centering point for the

22



entire template! "t is also possible to s6ew the template from the center by using the TemplateS6ewing ialog! S6ewing can be used to perform off:end shooting geometries!

Salvo Shooting handles scenarios of multi:source salvos that span receiver lines andsalvos that re-uire restricting the inline template roll! Salvo shooting is very well suited for slant geometries and bottom:cable designs! "n our terminology; a salvo is a set of source points <in a single source line= that is locatedbetween two receiver lines! 7ne source point or twenty source points can represent a salvo::itdepends on the layout of the survey! The screen capture below shows source lines in a variableline spacing receiver grid! The salvos are represented in 3 and ( source point groups!

)abel ased Shooting shoots surveys using the labeling numbers; not the internal numbering! "tis convenient for shooting geometries which have a large number of sources shooting into areceiver patch <bottom cable surveys; for example=! $rior to entering )abel ased Shooting; you need to examine the labeling scheme in your survey!"n the diagram below; the first receiver point is labeled ,/,0/,! The receiver inline increment isone <,/,0/%; ,/,0/3; etc=! Moving to the first point on the second receiver line; ,/00/,; the lineincrement is (///! The label of the first source point is 0/,,/,! The source inline increment isalso one! The label number of the first source on the second line is 0/+,/,; so the crosslinelabeling increment is *///! )abel Shooting operates on these point and line increments; so it isimportant to 6now these values!

23



oth the Swath and &eneral Se-uence shooting functions are largely archaic! Most surveys canbe shot more easily using another techni-ue in the program! owever; the methods are left in theprogram in case some unusual circumstance warrants their usage! These methods will only wor6if your survey design is orthogonal and very; very regular!

Swath Shooting can be used for very simple shooting situations2 only two roll instructions from theinitial template and source positions are allowed! To use Swath Shooting; the rolls within eachswath must be consistent; and the roll from swath to swath must be consistent; therefore it is notpossible to shoot a bric6 survey in a single pass via Swath ShootingU 7ne instruction is used tospecify how to move the template along the swathV The other instruction specifies how to movefrom swath to swath!

&eneral Se-uence Shooting is used for more complicated shooting situations; such as bric6s! "n&eneral shooting; there can be an unlimited number of shooting instructions! Each instructioncan move the receiver template inline and5or crossline; and each instruction can move inlineand5or crossline to the next source! The goal of &eneral shooting is to generate a set ofinstructions which can be repeated to shoot all or a portion of the survey! There are two types of instructions in &eneral shooting; W"nner MovesW and W7uter Moves!W "nnerMoves can be thought of as instructions which get repeated until the edge of the survey is hit;much li6e the Wfirst move directionW instruction in the Swath shooting methodology! 7uter Movescan be thought of as instructions which get carried out when an "nner Move instruction cant becarried out <i!e! : the edge of the survey has been hit=; much li6e the Wsecond move directionWinstruction in the Swath shooting methodology!

Manual Shooting is used to manually position a defined template and then fire the desired sourcesinto that template! The template can then be shifted to a new position to fire the next source or groupof sources!

All of these shooting techni-ues can be limited by specifying ranges of sources and5or receivers or by using attributes and filtering options! )imiting allows you to change the siBe; shape; andorientation of templates across the survey!

9oll:on can be activated or the patch can be held stationary at the edge of the survey! Templateswithin the survey can be selectively unshot# for single sources or groups within the Edit Sources

24



mode! "f sources are moved after firing; the midpoints will also be shown moving! This is a usefuldiagnostic when trying to increase the fold in an exclusion Bone either by moving existing sources;firing into new templates; or adding compensation sources!

There are several 6eyboard shortcuts that can be used to -c or speed up shooting2

;ey Action T Toggles on5off the template while shootingV Source colors continue to update! S Toggles on5off real time updating of the display while shooting! The display updates after a

group of 0// sources has been fired! $ $ause the shooting! The current template is displayed! @ $ause the shooting and step to the next source while paused! C 9esume shooting after pausing 'ully unBooms the esign GindowEsc Cancels shooting

25



Shooting techni9ues compared

Shooting (ype *n,ormation

Automatic TemplateCentering

.ses Surveys with fairly uniform receiver lines; surveys with regular or irregular source lines

)imitations Template siBe is static

Salvo Shooting .ses Slant surveys; source patterns that span receiver lines

)imitations Templates may not position correctly at survey edges; alwaysuses all sources between receiver lines

7ffset Shooting .ses Surveys with highly irregular receiver positions; surveys withregular or irregular source locations; limited offset range shooting

)imitations Creates a lot of templates; slower shooting method; only createsa circular patch

9ectangular Shooting .ses Surveys with highly irregular receiver locations <especially for imported surveys=; surveys with regular or irregular sourcelocations; surveys where template siBe can vary

)imitations May not 6eep all sources in a salvo together in the same patch

)abel ased Shooting .ses Creating complex templates; creating large source patches

)imitations Survey labeling must be regular and consistent

Swath Se-uenceShooting

.ses Surveys with regular source and receiver lines

)imitations Method is extremely sensitive to survey irregularities; difficult to

use; other shooting options produce the same answer

&eneral Se-uenceShooting

.ses Surveys which are difficult to shoot with Swath Shooting in onepass

)imitations Method extremely sensitive to survey irregularities; most difficultmethod to use; other shooting options produce the same answer

Manual Shooting .ses &ood for shooting individual sources that have been added; goodfor lassoing large groups; possible to shoot individual sourceswhich cannot be fired in any other way

)imitations Fery labor intensive; Edit Templates feature offers better methodof manual shooting

.nit Template Shooting .ses Shooting complicated geometries e!g! button patch; slash <ig or ag= and variable spacing; use with a pre:defined surface or sub:surface polygon fill!

)imitations .nwanted receivers may be generated; survey layout coincideswith shooting so not applicable to surveys which are already laidout!

26



!inning

The default bin siBe is half the source and receiver interval! The bin grid will default to the minimumand maximum receiver bounds rather than the edge of the midpoint coverage!

The siBe; orientation and relative positioning of the grid are set by the mouse or 6eyboard and can be

changed for the analysis of various processing parameters! "t is also possible to use place:holders or 6ey:positions to align the grid and thus maintain a consistent grid between design and processingstages!

"t is possible to save and review binned attributes by naming the calculation and then later selectingit! The 'old Selection option in the in Analysis menu is used to select the named calculation to use!The 'old Compare option is used to compare two named fold calculations! "t creates a folddifference plot!

@2 "f you redefine the bin grid or reshoot the survey after calculating attributes; you will need torecalculate to view the effect!

Attribute +alculationMESA allows for several types of bin attribute calculation2

'old only a -uic6 loo6 techni-ue for analyBing fold

'575A create all fold; offset and aBimuth attributes for the whole survey

C9$ binning used in combination with 3Aims this function provides for binning on asubsurface structure thus producing C9$ rather than CM$ cover

Multi:Falued lets you examine fold for particular instrument component combinations

'lex inning set a flex radius to include midpoints from surrounding bins in each bin

Partial survey

The Calculation Extents options can be used to calculate the desired information for alimited geographical region of interest! The region can be defined either manually byentering a range of grids to use or by graphically selecting the grid range with the mouse!

7nce the bin attributes have been calculated a series of QC plots become available in the esignGindow and under the in Analysis menu!

$lease be aware that the bin and midpoint files can be very large for large surveys and thereforecalculation and display may ta6e some time!

27



(he !in Attribute Plot

This information can be accessed through either the esign Gindow or the in Attribute Gindow!These windows provide access to the main survey QC screens! Ghen the in Attribute Gindow isopened; the bin grid is displayed! After the Mouse "dentification mode has been set to ins; holddown the Shift 6ey and )eft:Clic6 on a bin to display the bin information dialog!

'old can be shown as a color:fill plot or numerically! The colors in the display may be changed byusing the interactive color scale! The entire fold can be displayed; or ?ust the fold for limited offset or aBimuth ranges! "t is also possible to set a Mute 'unction <offset or first brea6= in the in Analysismenu and then apply one or both of these mutes to the fold! e aware that setting the mute functionon for the fold will also apply the mute to the offset and aBimuth displays!

The default offset plot is a blac6 and white stic6 histogram in each bin with each line representingone midpoint! The x:axis of the histogram corresponds to the inline bin direction! The scaleranges from Bero offset on the left edge of the bin to survey max offset on the right edge of thebin! The y:axis is scaled exactly the same way; so the longer histogram lines represent traceswith longer offsets! &aps in the histogram reflect a discontinuous offset distribution! This plotmay be changed to a color histogram where the midpoints are summed according to offset range

and color coded by redundancy! Set the number of histogram lines in the 1 istograms edit box!The survey maximum offset distance is divided by 1 istograms to establish a series of offsetranges! Midpoints are summed for each offset range! A histogram leg is plotted at the center of each offset range; and is color coded by the number of midpoints in the range! M7 andmigration will move trace energy across surrounding bins so it is more important to consider thecontents of a neighborhood of bins; than to consider individual bins! The window can also be used toshow color:fill plots for selective offset ranges; the @ear 7ffset plot is especially useful whenanalyBing the effect of exclusion Bones; and the 'ar 7ffset for ensuring that the depth of target will bereached!

ABimuths are plotted as a spider in each bin where the length of the leg is proportional to the offsetfor that midpoint; and the direction of the leg denotes the aBimuth! Color spiders <color denotesoffset=; ball plots; circle plots; and trace aBimuth plots can also be shown!

Combination plots can be created by displaying fold; offset and5or aBimuth plots simultaneously!Mega:Spider plots can also be displayed on any plots! Ghen Mouse "dentification is set to ins; holddown the Ctrl 6ey and )eft:Clic6 on a bin to display the Mega:Spider for that bin!

(he !in Attribute Graph

This plot provides a mechanism for viewing all the information along a bin line in either the inline or crossline direction! The in &raph 7ptions dialog allows the user to select the active parameter for the y:axis and for the color; both to be plotted against bin number on the x:axis! Thus each verticalcolumn is the CM$ bin containing cells# of offset usually chosen as the group interval! The default isto plot offsets on the y:axis and aBimuths by color as this is the most useful for viewing the effect of exclusion Bones! This plot appears as a series of F# shapes in which all of the possible offsets aredefined for use in velocity analysis! The Show Cross Section in esign Gindow option plots a line toshow the currently displayed bin line in the esign Gindow!

(he !in Statistics <indo-

The in Statistics Gindow offers a statistical summary of all midpoint information in the survey!The H and D axes change depending on the type of graph you select! The axes can representpercentages; actual numbers; fold; offset; etc! Dou have the option of displaying a fold graph; anoffset graph; an aBimuth graph; a rose diagram; or an offset fold chart! A statistical window fordisplaying a textual summary of bin attribute information is also available!

28



E=E2+*SE >1 // !asic MESA 'sage

This exercise shows the basic se-uence of steps for creating a survey in MESA! Dou will belaying out sources and receivers; translating the survey; shooting the survey; defining a bin grid;calculating diagnostics; and outputting the survey to SE&:$, files!

ifferent types of geometries can be created in MESA! )ayout types such as slant; Big:Bag;radial; button; random; etc! can all be created! This exercise will focus on a simple; straight lineorthogonal layout!

1%5 'rom the .ayout menu; select the 2eceivers option! This will open a submenu of receiverlayout options! 'or this exercise choose the .ines?!ric0s option! This will open theI)ine5ric6 )ayoutJ dialog!

The I)ine5ric6 )ayoutJ dialog is used to define the parameters for the receivers in asurvey! )aying out sources uses a very similar dialog! Dou need to specify the inline andcrossline spacings; line bearings; starting coordinates; and survey siBe! Survey siBe can beset in several different ways in MESA2 first by declaring the number of lines and thenumber of receivers to be included in each of those lines; second by declaring the inline

and crossline siBes; or third by filling in a previously defined area; either an exclusion Boneor source lines! )ater exercises will show how to use these fill options for determiningsurvey siBe! The bric6 options are used to create bric6 surveys instead of orthogonal!"nstrument types and numbering can also be defined in this dialog!

'ill in the receiver I)ine5ric6 )ayoutJ dialog as shown on the next page!

29



Clic6 on the 6umbering button to specify the survey numbering you wish to use! Anynumbering that you set in this dialog will be used for any sources or receivers you lay outafterwards! 'or this example; use MESA#s default numbering system!

Also note that you can specify receiver and source line prefixes and suffixes; which can bealphanumeric!

30



Clic6 on the *nstrument button to enable the following dialog; in which you can definevarious instrument types2

Again simply use the default value! Close the Iefine "nstrumentJ dialog and press the O; button in the I)ine5ric6 )ayoutJ dialog to lay out the receivers!

&%5 @ow lay out the sources! Select Sources /@ .ines?!ric0s from the .ayout menu! Thiswill open the I)ine5ric6 )ayoutJ dialog for sources! Dou will need to fill in the dialog as itappears below! "t wor6s exactly li6e the receiver dialog! After you parameteriBe yoursource layout and press O;; the sources will be displayed and your esign Gindow shouldloo6 li6e the picture on the next page!

31



)%5 Dou can set the units for the measurement system at any time! Select the 'nits optionfrom the .ayout menu and toggle on the desired system of units2

%5 @otice that the header line on the esign Gindow reads IKuntitledXJ! This indicates thatthe database has not been saved! Save the design by opening the File menu and

selecting Save Database! Enter the name Iexercise/,J at the File 6ame prompt andpress Save! IKuntitledXJ is now replaced by Iexercise/,J in the esign Gindow title bar!

Dour design is a <+4%/# x +4%/#= %!%0 s-uare mile 3: survey! 9eceiver interval is ,,/#;receiver line interval is ((/#; source interval is ,,/# and source line interval is 88/#! Thereceiver line aBimuth is 4/ degrees from true north and the source line aBimuth is truenorth! The initial source and receiver positions have each been offset from </; /= by 00# intheir inline directions!

32



B%5 Select (ranslation from the 'tilities menu! The ITranslation59otationJ dialog is used tochange the coordinates and the aBimuths of the survey! Changing both the coordinatesand the aBimuths is a two step process! 'irst do the Coordinate Translation! This can bedone graphically or by specifying actual figuresV fill it in as below and press O;%

@ext open the ITranslation59otationJ dialog again and do the Coordinate 9otationV this can bedone graphically or by specifying figuresV again fill it in as below and press O;%

33



$ress the Full 'n#oom button on the oom toolbar in the esign Gindow and you will see thatthe survey has been translated to the new location and rotated to the specified angle!

34



C%5 The esign Gindow should now loo6 as it does above! The oom toolbar; shown below; isused to ad?ust the display and contains the 2ange?!earing tool! Dou can Boom in on thesurvey with the right mouse button! $ress and hold the right mouse button to draw a Boomrectangle! Ghen you release the right mouse button; the display will update to show you

?ust that region! Dou can perform the Boom function multiple times! To Boom out one stepfrom the current Boom level; press the oom Out 1 .evel button; the magnifying glass withthe O signV if you are already at the full Boom level pressing the oom Out 1 .evel buttonBooms you out by another 0/R! To Boom to ,//R of the full view; press the oom Out1 button; the magnifying glass with the letter '! The Aspect 2atio button has the xLyon it! As long as this button is down; the survey is always displayed at a fixed ration! "f thebutton is not depressed; then the survey will be displayed at the ratio defined by the siBe ofthe esign Gindow!

%5 7pen the Find 2ecord or !in button submenu and verify that the mouse is set to identify

2eceivers and Sources! old down the Shift 6ey and )eft Clic6 on a source in the esign

Gindow! The following dialog will appear2

35



Change any of the editable fields and press Apply to edit the information for this source!$ress the Spreadsheet button to go to the spreadsheet entry for this source! $ress the*nstrument button to modify the instrument settings for this source! @otice that the livereceiver template for this source is highlighted in the esign Gindow if you have shot yoursurvey! olding Shift and )eft Clic6ing on a receiver will open the same dialog with theinformation for the receiver!

7nce you are in the spreadsheet <you can also access the source and receiverspreadsheets by selecting 2eceiver Spreadsheet or Source Spreadsheet under the.ayout menu=; you can 9ight Clic6 with the mouse in any cell to bring up a menu of editingfunctions!

Dou can also change the source or receiver information with the Edit toolbars! Select theEdit option from the 2eceiver Display?Options or Source Display?Options buttonsubmenu! A later exercise will go into more detail about the Edit toolbars!

36



%5 @ow you can create a template and shoot your survey! $ress the Shoot button to open theIShootJ dialog! Many different methods of establishing source and receiver relationshipsare available in MESA! As the shooting process progresses; source points will changecolor in the esign Gindow and their associated receiver patterns will be highlighted!Selecting the appropriate shooting algorithm will depend upon the geometric relationshipbetween your source and receiver points! Dou will be using Automatic (emplate+entering in this exercise! )ater exercises will demonstrate how to use some of the othershooting methods!

7nce you have opened the IShootJ dialog; press the +reate (emplate button and definean 8 line by (8 receiver shooting patch! This template will be displayed in the Select(emplate list in the Template 7ptions section! Select the template and press the Shoot button! The dialog will close and MESA will begin to simulate shooting the survey in theesign Gindow! 7nce it is finished shooting; all of the sources will be displayed in red;meaning they have been fired! Select Edit (emplates from the 'tilities menu to view theresults! )eft clic6 on a source to view the receiver patch for that source! &o bac6 into the'tilities menu and select Edit (emplates again to exit this mode!

37



H%5 The next step is to define the bin grid! Select !in Grid Settings from the Display !ins button submenu to open the Iin efinitionJ dialog! 'ill in the *nline and +rossline !inSi#e boxes as shown! Clic6 on the Auto Fit button to automatically fill in the remaining textboxes! Select O; and the bins will be defined! To view the bin grid; Boom into a small areain the middle of the survey and depress the Display !ins button!

38



1%5 @ow that you have shot the survey and defined a bin grid; you can calculate the fold andmidpoint attributes! Select Fold +alculation from the !in Analysis menu to open theI'old CalculationJ dialog! Choose the option to calculate the Fold7 O,,sets7 and A#imuths and press O;! After the calculations finish; the Fold Graph; O,,set Graph; A#imuthGraph; and 6oise Graph buttons; on the in Attributes toolbar; become active! oom intoan area of the survey and press these buttons to view the attributes!

11%5 After you are finished laying out and editing the survey; the survey information can bewritten to a variety of output files! 7ne very useful format that has industry:wideacceptance is the SE&:$, ASC"" survey format! Dou can export the survey information tothis format with the SEG/P1 option in the Output menu2

39



$ress the File button in the Source 'ile section and type IoutputYexer/,!srcJ at the I'ile@ameJ prompt; and select Save! $ress the File button under the 9eceiver 'ile section andtype IoutputYexer/,!rcvJ at the I'ile @ameJ prompt and select Save! These two files will beused in later exercises! $ress O; to create the files!

40



DO IT YOURSELF #1

'rom the File menu; select the 6e- Database option! Save your current database whenprompted to do so!

)ay out a survey using the following parameters2

9eceiver "nline Spacing2 0/ m9eceiver Crossline Spacing2 %// m9eceivers $er )ine2 (%@umber of )ines2 ,,9eceiver "nline earing2 4/ degrees9eceiver Crossline earing2 / degreesH:Coordinate of ,st 9eceiver /!/D:Coordinate of ,st 9eceiver /!/

Source "nline Spacing2 0/ mSource Crossline Spacing2 %// mSources $er )ine2 (/@umber of )ines2 ,,Source "nline earing / degreesSource Crossline earing 4/ degreesH:Coordinate of ,st Source %0!/D:Coordinate of ,st Source %0!/

Save the survey with the name IbasicJ!

41



E=E2+*SE >& // .ine?!ric0 .ayout Options

This exercise demonstrates some of the different layout options avaiable for line5bric6 layouts inMESA! Dou will be creating three surveys in this exercise! The first survey will be completelyuniform and will use se-uential numberingV the second survey will have variable receiver linespacing and will be numbered with the grid based methodV the third survey will use slanted

source lines!

,!= Start MESA; or select 6e- Database from the File menu if you have a survey already loadedin MESA! Dou will be creating a simple straight line orthogonal survey! Select 2eceivers I.ines?!ric0s from the .ayout menu! 'ill in the I)ine5ric6 )ayoutJ dialog as it appearsbelow! $ress the 6umbering button to open the I@umberingJ dialog!

%!= A uni-ue identifying number is usually created by combining a line number with a number forthe receiver or source! 'or example; if the first receiver line of a survey is called the ,/,line and the first receiver on that line is called 0/,; then the receiver point is called ,/,0/,!The next point on that line will be called ,/,0/%! "n the survey you are laying out; there willbe * sources per source line between each receiver line! ecause of this; the receiver linenumbering interval will increment by *; the ,/, line; the ,/+ line etcZ So the first receiver

on the second receiver line will be ,/+0/,! The sources will start with )ine 0/, and thesources will start numbering with ,/,; so the first source is 0/,,/,! Since there will be 8receivers per line between each source line; the source line will increment by 8; so the firstsource of the next line will be 0/4,/,!

Survey @umbering can be done during source or receiver layout or by using the2enumbering option in pull down menus from the source5receiver display buttons!@ormally numbering assumes a uniform spacing where you can supply a numberingsystem that will label every point in an ordered fashion! The numbering system can be

42



used to indicate spatial location; in addition to simply labeling the sources and receivers!Se-uential numbering wor6s fine as long as the survey is uniformly spaced! "f the surveyhas varying line spacing or point intervals; se-uential numbering will not wor6 properly!&rid based numbering was developed for non:uniform surveys!

'ill in the I@umberingJ dialog as it appears below! The First 2eceiver field contains the fulluni-ue identifying number for the first receiver! The 2eceiver *nc field contains theincrement for numbering the next receiver in line! The 2eceiver .ine *nc field contains theincrement for numbering the first receiver of the next line! MESA will determine whatportion of the number is a )ine @umber with this increment! Dou can also specify a )ine@ame $refix or Suffix in this dialog! The )ine @ame will be created by ta6ing the )ine@umber and adding any prefix or suffix that is specified! @otice that you can define thenumbering for both receivers and sources in this dialog! Dou only need to define thenumbering for each once! Any sources or receivers that you lay out after setting thenumbering will use the defined se-uential numbering scheme!

7nce you have filled in the I@umberingJ dialog; press O; in it and then press O; in theI)ine5ric6 )ayoutJ dialog to lay out the receivers! $ress the .abel Display?Options iconto display the receiver labels in the esign Gindow; as shown below!

43



3!= @ow lay out the sources! Select Sources I .ines?!ric0s from the .ayout menu! 'ill in theI)ine5ric6 )ayoutJ dialog as it appears below! Since you set the source numbering at thesame time as the receivers; you do not need to open the I@umberingJ dialog again!isplay the labels once the sources are laid out and the esign Gindow should appear thesame as below! Save the survey as Iexercise/%YregularJ!

44



(!= The se-uential numbering system will not wor6 as reliably for the next survey! Dou will belaying out new receiver lines with variable spacing! 7pen the I)ine5ric6 )ayoutJ dialog forthe receivers! 'ill out the dialog as it appears below! @otice that when you chec6 the 'se3ar% +rossline Spacing option; the 3ariable button becomes active! $ress the button toopen the IFariable Crossline SpacingsJ dialog! 'ill it in as shown and press O;! $ress theO; button in the I)ine5ric6 )ayoutJ dialog to lay out the receivers! Select 2emove whenprompted to remove the existing receivers!

The survey will now have receiver line intervals of 3//; %//; and ,// instead of the uniform

3// and should appear as below! The line numbering won#t be able to increment by aneven * as it did before since between any % ad?acent receiver lines there are either %; (; or* source points on any one given source line! "deally the goal would be to have line one be,/,; line two be ,/+; line three be ,,,; line ( be ,,3; and line 0 be ,,4! This is not ase-uential se-uence!

45



0!= Gith the new receiver lines displayed; select 2enumbering : Grid !ased from the 2eceiverDisplay?Options button sub menu! &rid based numbering renumbers the survey byplacing a user:defined grid on the survey and numbering that grid se-uentially! Anytime areceiver line or point occupies a part of the grid with a number associated with it; the pointwill get that number! The grid is given a reference number similar to the starting number inthe uniform survey; ,/,0/,! The grid is defined so that it will occupy every possiblelocation of a receiver line or point! "n this example the grid spacing is 0/ in both the inlineand crossline direction since 0/ is the source spacing and we want to reflect the number ofsources between each pair of receiver lines! The grid is defined to increment by , in theinline direction and by ,/// in the crossline direction!

$ress Auto Fit to automatically fill in the &rid 9eference fields! 'ill in 0/ for both the *nlineand +rossline Grid Spacings after you have performed the Auto Fit calculation! $ressO; after filling out the I&rid ased 9enumberingJ dialog as shown! MESA has nownumbered a variable line spaced survey in the same reliable manner as that of a uniformlyspaced survey!

Select Save As 6e- Database from the File menu to save this survey under a new name!Save the survey as Iexercise/%YvariableJ!

46



*!= 'inally we will use the Slant option to create a survey with a slanted source layout! Select6e- Database from the File menu! 'rom the .ayout menu; select 2eceivers; and then the.ines?!ric0s option! 'ill in the I)ine5ric6 )ayoutJ dialog as shown and clic6 on O;2

47



+!= @ext; use the .ines?!ric0s option to lay out the sources! 'ill in the dialog as follows! Ghenyou chec6 the 'se Slant Parameters option; the Slant button is activated! $ress thebutton to open the ISlant )ayout $arametersJ dialog! Set = Moveup to ,,/; J Moveup to%%/; and .ine Spacing to ,3%/! $ress O; in both dialogs to lay out the sources!

48



8!= Save the survey as Iexercise/%YslantJ! Dour survey should loo6 li6e this2

49



DO IT YOURSELF #2


esign a survey with the following dimensions! The receiver and source numbering shouldmatch as in the exercise/%Yregular and variable surveys! .se ,/,0/, for the first receiver and0/,,/, for the first source!

Survey SiBe2 0mi x 0mi; <%*(//# x %*(//#=

9eceiver "nterval2 %%/#9eceiver )ine "nterval2 ,,//#9eceiver )ine "nline earing 4/ degrees9eceiver )ine Crossline earing / degreesH:Coordinate of ,st 9eceiver */048(!//D:Coordinate of ,st 9eceiver ,*004+(!//

Source "nterval2 %%/#Source )ine "nterval2 88/#

Source )ine "nline earing / degreesSource )ine Crossline earing 4/ degreesH:Coordinate of ,st Source */08+(!//D:Coordinate of ,st Source ,*0*/8(!//ric6 $attern 0 sources5bric6; %:line repeat

in SiBe ,,/# x ,,/#Shooting Template ,% x +%

SAFE AS multi,

50



E=E2+*SE >) // 'nit (emplate .ayout

This exercise demonstrates how to use the 'nit (emplate option for laying out a 3: seismicsurvey! Dou will be creating a 3: survey in this exercise by filling a survey boundary! The surveywill be a bric6 pattern that will be used later in the course!

,!= Start MESA; or select 6e- Database from the File menu if you have a survey alreadyloaded in MESA! Choose Edit Exclusions from the Exclusion Display?Options buttonsubmenu! This will open the Edit Exclusions toolbar2

%!= Chec6 that the +reate Exclusion icon is selected! Choose the Survey !oundary iconfrom the possible exclusion types! Dou can 6eep the default @ame; if desired; but youmust specify a )ayer for the exclusion! Select K@ew )ayerX in the layer list and create alayer called IoundariesJ!

3!= @ext; clic6 on the De,ine Exclusion icon! The following dialog will appear2

@ote that you can specify the color; the infill pattern; and what will be excluded for theexclusion Bone in this dialog! Since you will be filling this boundary with sources and

receivers; toggle off all of the options in the Exclude box!

(!= $ress Exclusion De,K; and enter the following H;D coordinates to define the surveyboundary! 9emember to press the Add button after typing in each H;D coordinate pair!

<*%%(8(; ,*+(*+(=; <*%%(8(; ,*4/0,(=; <*33/((; ,*4/0,(=; <*33/((; ,*80%3(=;<*383%(; ,*80%3(=; and <*383%(; ,*+(*+(=

Exit the exclusion editing mode by selecting Edit Exclusions from the ExclusionDisplay?Options button submenu again!

51



0!= Select 'nit (emplate from the .ayout menu! This will open the .nit Template window!$ress the .ayout (emplate icon to create your unit template! "t will as6 you to first set thegrid siBe for use in laying out the template! Set the grid siBe to ,,/! After you set the gridsiBe; the ITemplate )ayoutJ dialog is displayed! Enter the numbers as they appear in thedialog below! The template is a ,/ x *( patch; receiver interval %%/#; and receiver lineinterval 88/#! $ress Apply to layout the receivers! The sources need to be centered in themiddle of the receivers! There is one line of ( sources that will be fired into each set of ,/ x*( receivers; and the sources have a %%/# interval! The starting coordinate centers thesources! $ress Apply under the Source )ayout section to add the sources to the template!Dou could continue to add or replace receivers or sources to create more complextemplates! Select Exit to finish laying out the template!

52



*!= 7nce you have finished laying out the template; there are editing options available in the.nit Template toolbar! Dou can add; move; or delete any of the sources or receivers! Doucan also add; copy; move; or delete entire templates! 'or this example the desired sourcepattern is a ,3%/# source line interval bric6ed at **/#! The template needs to be copied onetime from its current location to a location 88/# in the vertical direction and **/# in thehoriBontal direction! Select the Ma0e?+opy (emplate icon to open the ICopy [ Move7ptionsJ dialog! Choose +opy (emplate and set = to **/ and J to 88/! $ress O; todisplay the updated template!

+!= At this point the template can be repeated to lay out and shoot the survey! Select the

Shoot Options icon from the .nit Template toolbar to open the I.nit Template 9epeatJdialog! Enter the values as shown on the next page!

Dou will be setting the siBe of the survey by filling the exclusion Bone that you defined at thebeginning of this exercise! The Clipping section sets how the survey siBe area is filled!Clipping the 9eceivers5Sources means that the receivers and sources fill ?ust the definedarea! Clipping the fold means that enough sources and receivers are added to provide fullfold in the defined area! "n this example; you want to have sources and receivers in thedefined area only; so select +lip 2eceivers?Sources to !ounds! Supply ,3%/ for the*nline and ,+*/ for the +rossline spacings at which to repeat the unit template! TheTemplate 9eference $oint defines where to start the template layout! Dou want to start thetemplate from the corner of the survey boundary! $ress the Select Point button tographically set the starting point for laying out the templates! ighlight the receiver at

<**//; 30%/= as the starting point and select the Shoot Options icon again! $ress O;7 and the survey will be laid out and shot in the boundary!

53



The esign Gindow should now have a survey similar to the one below! This survey has areceiver interval of %%/# and a receiver line interval of 88/#! The source interval is %%/#; andthe source line interval is ,3%/# bric6ed at **/#; shot with a ,/x*( template! Since the bingrid is placed automatically with this layout method; you can go immediately to the !inAnalysis menu and select the Fold +alculation option to calculate the fold and midpointattributes!

Save this survey as Imulti%J! Dou will be using it again in a later exercise!

54



DO IT YOURSELF #3


Select Edit Exclusions from the Exclusion Display?Options button submenu! $ress the 2eadExclusion File button and load the exclusion file called multi%!xcl! This loads the exclusion Bonefrom the multi% survey into the new survey! Exit the edit mode by selecting Edit Exclusions again!

@ow use the .nit Template Gindow to lay out the survey! Create a template with the sameparameters you used in Exercise 13! Dou will be creating an orthogonal survey this time; so youdo not need to copy the template! "nstead choose Move (emplate4s5 and shift the H Coordinateby ,,/!

"n the I.nit Template 9epeatJ dialog; choose Fill Polygon; +lip Fold to !ounds; set *nline and+rossline Spacings to 88/; Auto/+alculate 2e,erence; and set Speci,y .ine !earing to 4/!o not chec6 the option to 'se Full (emplates! This will layout a survey that has ?ust enoughreceivers and sources to generate full fold in the exclusion Bone! Select Fold +alculation fromthe !in Analysis menu to loo6 at the fold coverage!

After you loo6 at the fold coverage; go bac6 to the .nit Template Gindow and re:open the J.nitTemplate 9epeatJ dialog! .se the same settings; but this time chec6 the option to 'se Full(emplates! Also ma6e sure that you chec6 2emove Existing Survey! This will remove thesurvey and then lay out a new survey! The new survey will still have full fold in the exclusionBone; but now it has all of the receivers necessary for each source to have a full template!

7utput the survey information into SE&:$, files called IoutputYexer/3!srcJ andIoutputYexer/3!rcvJ!

55



E=E2+*SE > I (he Design Guide

This exercise demonstrates the use of the esign &uide to aid in the layout of your survey! Douwill be defining an exclusion Bone and filling it with sources and receivers! Dou will use theesign &uide to determine the source and receiver spacings; bin grid siBe; and template siBeneeded for your desired target parameters!

1%5 Start MESA or select 6e- Database from the File menu if MESA is already running!Create a new survey boundary exclusion Bone! .se the layer name IoundariesJ for thisexclusion and give it the following coordinates2

<:0/; /=; <%(//; /=; <3%*/; ,04/=; <3/4/; %(+/=; <%(3/; %80/=; <,/0/; %4//=; and <:0/; ,0//=

After you have finished laying out the exclusion Bone; save the database as Iexercise/(J!"t should loo6 li6e this2

56



&%5 .nder the .ayout menu; select the Design Guide option! 'ill in the interval velocity attarget; the dips; and the horiBon time for the Bone of interest; as shown in the followingdialog2

@otice that the edit boxes in the (arget Parameters group box are tied to the fields in the

!in Si#e group box; so changing information in one area automatically updates informationin the other area! Max bin siBes are calculated for both inline and crossline dips! Changethe bin siBe to %0 m in each dimension and the Max 9ecoverable 're- increases to ,/0!3!The following e-uation is used to 6eep the values in the (arget Parameters group boxconsistent with the values in the !in Si#e group box2

!in Si#e

!in Si#e L "nt Felocity at Target 5 <(!/ Max 9ecoverable 're-uency sin <ip Angle==

)%5 @ext; change the source and receiver intervals to be twice the bin siBe; or 0/ m! Dou canexperiment with various line spacings; but choose %// m for both source and receiver linespacings!

3ertical 2esolution Estimate

Fertical resolution is based upon the interval velocity at the target and the bandwidth of therecoverable fre-uencies!

Minimum 3ertical 2esolution L "nt Felocity at Target 5 < (!/ <Max 're- O Min 're-= =Maximum 3ertical 2esolution L "nt Felocity at Target 5 < %!/ <Max 're- O Min 're-= =

57



.ateral 2esolution Estimate

.ateral 2esolution L 3!/ Minimum Fertical 9esolution 5 sin <Maximum ip Angle=

6O(E The factor of 3!/ comes from an estimate that it ta6es 3 seismic traces to identify ageologic feature!

6ominal Fold +alculation

6ominal Desired Fold L <@umber of Channels Min in SiBe= 5 < %!/ )ine Spacing=

6O(E )ine Spacing is the smaller value of source line spacing and receiver line spacing! Any change to the template siBe; bin siBes; or line spacings will regenerate the nominal foldvalue shown in the esign &uide!

%5 Clic6 the 3elocity Function button to open the IStretch Mute Time5Felocity $airsJ dialog!This dialog is used for entering time:velocity pairs and calculating a stretch mute!

Change the Stretch Mute Percent to /!%0 and then enter the following time:velocity pairs;remembering to press Add after typing in each pair2

<*//; ,8//=; <,///; %(//=; <%///; 3///=; and <3///; 3*//=

"f you need to remove a time:velocity pair; select the pair in the list and then clic6 on theDelete button! "f you need to edit a pair; select the pair in the list; ma6e the appropriatechanges in the Time or Felocity edits; and then select a different pair in the list to apply thechanges! Clic6 on O; to save the changes to the stretch mute! The mute will be drawn inthe Mute 'unctions window! This mute can be applied in the .imits options of any of thebin attribute displays!

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B%5 @ext; press the +alc Mute O,,set button to bring up the following dialog2

The effects of the mute function can be seen for offsets in increments of ,// units! "naddition; the mute offset at the target is listed; along with the maximum minimum offset forthe survey!

Max Minimum O,,set ≅ < 22 SL RL + = : SA

Ghere 9) is 9eceiver )ine Spacing; S) is Source )ine Spacing; and SA is the salvo

ad?ustment! The salvo ad?ustment corrects the offset for sources not being concurrent with

receivers! The ad?ustment is <int<9)5SS= /!0 O /!0= SS; where SS is the Source

Spacing!

Clic6 on O; to exit this dialog!

C%5 @ext; clic6 on +alc (emplate Si#e%

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@otice that spacings are given for the fold; and the max minimum offset is listed as well! "fyou change the source line spacing; the receiver line spacing; or the number of channels;press +ompute (able to recalculate the data in the list box! Specify 38( as the 6umber o, +hannels; and clic6 on +ompute (able!

ased upon the e-uation for 6ominal Desired Fold; the suggested line spacings forachieving this fold value <as well as the maximum minimum offset value= are displayed inthis dialog!

efore exiting the dialog; you should select the desired template from the list box!Changes made in this dialog will be reflected in the main esign &uide dialog!

"n this case; select 8 lines with (8 channels per line and clic6 on O;! Clic6 on Done in theIesign &uideJ dialog when you are finished! Dou will then be as6ed if you wish to proceedto either the 'nit (emplate .ayout or the .ine?!ric0 .ayout! Select .ine .ayout and theparameters from the esign &uide will be transferred to that layout mode!

%5 'irst; for the receivers2

'ill the polygon that you defined at the beginning of this exercise by selecting the Fill one option!

Clic6 on O; to lay out the receivers!

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%5 And; for the sources2

Again; choose the Fill one option to fill the exclusion Bone you defined!

.nder Shi,t o, First Source; specify %0 for both the H and D values! This will offset thefirst source a distance of one:half a group interval from the starting receiver!

.nder !ric0 Options; toggle on the !ric0 Pattern and enter ( Sources Per Group with a

.ine 2epeat *nterval of %! Clic6 on O; to lay out the sources!

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Save the survey! "t should loo6 li6e this2

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E=E2+*SE >B // *mporting Survey Files

This exercise shows how to import coordinate ASC"" files to layout a survey in MESA!

The ASC"" files to be imported are the source and receiver SE&:$, files created from theIexercise/,J survey in Exercise 1,! MESA can import data from any columnar ASC"" file type!

,!= Dou will import the survey from the SE&:$, files! 'irst you will import the receivers!Select 2eceivers I File *mport from the .ayout menu! This opens the I9eceiver "mportSetupJ dialog! "f you are importing a standard file type; you can select the type from the listto automatically load the configuration file for it! Dou can also load your own configurationfile if you have created one for the file you want to import! Dou can then use the OpenData File button to specify the file to load! The configuration file will then be used to importthe data from that file! "n this case; you do not have a configuration file so you will have tomanually define the data to import from our file!

%!= $ress the *mport <indo- button! The "mport Gindow is used to manually define the datato import from a file! Dou can save configuration files in the "mport Gindow! Theconfiguration files ma6e it much easier to import multiple files that have the same format!Select the Open Data File icon and choose the ASC"" receiver file IoutputYexer/,!rcvJ thatwas created in Exercise 1,! That file will then be loaded in the "mport Gindow as shown onthe next page! Dou are now ready to define the variables!

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3!= The list box contains the variables to define from the data in the ASC"" file! Ghen you areinitially importing points; you must specify at least )ine @umber or )ine @ame; 9eceiver orSource; H Coordinate; and D Coordinate! After you have the survey in MESA; you canupdate points by simply specifying 9eceiver or Source and the information that you wish toupdate! 'or this exercise you will be defining the )ine @umber; 9eceiver; H Coordinate;and D Coordinate! As )ine @umber appears first in the list box; begin by defining thecolumns that represent the )ine @umber! .se the mouse to highlight the range of columnsfor that parameter in the file! After the information is highlighted; press the De,ine (ypeicon! "n the I'ormat efinition ialogJ; you specify the format of the variable and thedecimal location and press O;%

(!= After you have finished in the I'ormat efinition ialogJ; the information area of the"mport Gindow toolbar turns green and displays the information that you ?ust set! @ow is a

good time to set the first line to import as well! Gith the )ine @umber columns stillhighlighted; press the Set First .ine icon! This opens a dialog where you tell MESA whatthe first line with data in the file is! The dialog opens with a default value of the line that ishighlighted! "f you have highlighted something on the first data line; you can ?ust press O;to set that as the first line to import! 7therwise; you can type in the first line that you wantto import and press O;!

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0!= @ow that you have set the )ine @umber and the first line to import; select 9eceiver in thelist! ighlight the last four digits of the receiver number <///,=! $ress the De,ine (ype icon! "t should be "@TE&E9 by default; so simply press O;% Dou will be using thecombination options later to combine the 9eceiver and )ine @umbers! "n this case; youcould ?ust highlight the whole number and a few extra columns to the left for the 9eceivervalue! "f you highlight the whole number; you can turn off the combination options!

*!= The final things to set are the H and D Coordinates! 'or the H Coordinate; highlight%(+%/80/! The SE&:$, format has an implied decimal that must be added bac6 during theimport into MESA! "n the I'ormat efinition ialogJ; change the type to ')7AT <7.)E=!"n the ecimal $oint section; press the LL button to move the decimal point one place tothe left; ma6ing the H Coordinate %(+%/80!/! $ress O;! Choose D Coordinate; highlight*0%3+3//; and again change it to ')7AT <7.)E= and move the decimal point one placeleft!

+!= Dou can review what you have set by pressing the 2evie- +on,iguration icon! >eeppressing it to cycle through all of the items that you have defined! Dou can save thesesettings to a configuration file with the Save +on,iguration File icon! "f you have savedconfiguration files; you can load them with the .oad +on,iguration File icon! "f you did notwant to import the entire file; you can use the Set .ast .ine icon to set the last line of datato import! The last line to import is the end of the file by default!

8!= 7nce you are ready to import the file; press the Exit icon! MESA will as6 if you are readyto import the data! $ress Jes to continue with the importV $ress 6o to close the "mportGindow without importing anythingV $ress +ancel to return to the "mport Gindow! Ghenyou continue the import; the I"mport 7ptionsJ dialog opens! This dialog lets you remove orupdate existing records when you import! $ress the +ombination Options button! Since

you defined a separate )ine @umber and 9eceiver; you must combine them to create theuni-ue 9eceiver number in MESA! e sure that +ombine .ine 6umber and 2eceiver6umbers is chec6ed and that 2eceiver 6umber Digits is set to (! $ress O; here; andthen press O; in the I"mport 7ptionsJ dialog! The receivers should now be imported anddisplayed in the esign Gindow!

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4!= Select Sources I File *mport from the .ayout menu and repeat the previous stepsusing the source file <outputYexer/,!src= from Exercise 1,! Ghen you are finished; youshould see the survey displayed as shown! Save the survey as Iexercise/0J!

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DO IT YOURSELF #5

'rom the File menu; select the 6e- Database option! Save your current database as whenprompted to do so!

)oad the SE&:$, files you created in o "t Dourself 13! Save the survey as IfullfoldJ! Dou will bedoing more with this survey in a later exercise!

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E=E2+*SE >C // Marine Design

This exercise demonstrates the marine design capabilities of MESA! esigning marine surveysuses many of the same options as designing land surveys; including defining bins and calculatingattributes! "t is possible to generate sail lines in the esign Gindow and view any of the fold;offset; and aBimuth attribute displays available in MESA!

"n this exercise; you will create a marine sail polygon and a marine survey to fill the polygon!

,!= The first thing to do is define a marine sail polygon exclusion Bone! efine the exclusionBone ?ust as you did in Exercise 13; except use the !loc0 Polygon icon instead of theSurvey !oundary icon! ere are the coordinates for the polygon2

$oint 1,2 <,////; /=$oint 1%2 <%////; /=$oint 132 <%////; ,////=$oint 1(2 <,////; %////=$oint 102 </; ,////=

Ghen you are finished; the exclusion Bone should be displayed in the esign Gindow as itappears below! This exclusion Bone will be the boundary for your marine survey!

%!= 7nce you have created the exclusion Bone to fill; select Marine Design <indo- from the.ayout menu! This opens the Marine Gindow; and since this is the first time you haveopened the Marine Gindow for this database it also automatically opens the IEdit oatConfigurationJ dialog! This dialog is used to create or edit any of the boats in your marinesurvey! Most of the edit fields are self:explanatory! The oat Coordinate is only used for

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multi:boat configurations! "f you only have one boat; leave it at </; /=! 'ill in the IEdit oatConfigurationJ dialog as it appears below and select O;! The Marine Gindow will updatewith the boat you defined and should loo6 as it does below! At this point you can addanother boat; delete the boat; or edit the boat! The Edit Grid button can be used toredefine the grid for laying out or editing the sources or streamers!

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3!= 7nce you have finished setting up the boat configuration; select the 'nit +ell !inning iconto define the binning parameters! The I.nit Cell inningJ dialog is used to defineparameters for binning a unit cell! The unit cell is a repeatable unit containing the binattributes of the full fold area! The number of bins generated is larger than the actual Iunitcell;J but a sufficient number of bins is provided to create a diagnostic display! 'ill in thedialog as shown below! Select O; and the Marine Gindow will fill in accordingly! Thecurrent configuration and sail spacings will yield an ,8 fold survey!

(!= @ow you will use this boat configuration to generate a marine survey that fills the exclusionBone you defined! Select the Sail .ines icon to open the ISail )ines 7ptionsJ dialog! 'ill inthe dialog as it appears below! Dou are filling the exclusion Bone in this exercise; but it is

70



also possible to ?ust fill a rectangular area! The )ine earing defaults to the longestdistance across the defined area! Generate O,,lap extends the sail lines so that the areato fill is full fold! "f you do not generate offlap; the survey ends at the fill area boundary!Generate Sail .ines actually displays the marine survey in the main esign Gindow! "t isnot necessary to generate the sail lines to perform unit cell bin analysis in the Marineesign Gindow! Select O; after filling in the dialog! The main esign Gindow will updatewith the marine survey inside the defined polygon! Dour window should appear as on thenext page! oom into the northern most corner and hold down the Shift 6ey and )eft Clic6on a source! The ISource "nformationJ dialog will be displayed! "f you loo6 in the esignGindow; the source will be highlighted and the streamer positions for that source will bedisplayed!

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0!= "n order to generate and view the diagnostics; you will now need to define a bin grid to fitthe marine survey! Select !in Grid Settings from the Display !ins button submenu andfill in the Iin efinitionJ window as shown!

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*!= Select the Fold +alculation option from the !in Analysis menu and calculate Fold7O,,sets7 and A#imuths! 7nce the calculations are finished you can view all of the attributeplots for the marine survey! The fold plot should appear as it does below; showing ,8 foldthroughout the area enclosed by the polygon! Toggle off the display of the source points toimprove the visibility of the fold plot!

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E=E2+*SE > // 'sing GMG *mage

This exercise explains how to use &M& "mage to prepare images for use in MESA! &M& "magecan be used to warp an image to fit a 6nown group of points; crop an image; and shift an image!"t can also merge together layer files to ma6e one image! "n this exercise; you will georeferencea file by converting it to &M&#s image format! Dou will also use the warp tool to ad?ust an image!

,!= Start &M&:"mage and select the (*FF option from the .oad submenu in the File menu!Select the Iimage!tifJ file and clic6 on Open! The ICoordinate EntryJ dialog allows you toposition the image! This dialog is displayed if there is no georeference file with the image!Enter the following scale and coordinates for the image2

The HD coordinates correspond to the upper left corner of the image! Ghen thecalculations are complete; the image will be displayed! 'eel free to Boom and pan toevaluate the -uality of the image! This image shows a variety of real world obstacles thatwill need to be accounted for in the survey design!

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%!= Select the File menu and choose the Save .ayer File option! &ive the output file aname and press Save! The !lyr file extension will be appended automatically! Thegeoreferencing information is now stored with the image so it will be correctly siBed andpositioned when the )D9 file is opened in MESA!

3!= Select .oad/@!itmap from the File menu! )oad the Imap!bmpJ file! .se the defaults inthe ICoordinate EntryJ dialog! This image needs to be warped so that the 6nown points are

at the correct location!

(!= $ress the Add <arp +ontrol Point button! Clic6 in the center of the A dot! This opensthe ICoordinate EntryJ dialog! Change the whole number portion of the coordinates to0////; 0(///; leaving any decimal portion unchanged! This is the correct location for the Adot! $ress O;! A red dot is drawn to show the initial location and a yellow x is drawn toshow the updated warp location! At least three points need to be specified to warp animage! Change the center of the A# dot to 03///; 0//// and change the center of the Cs-uare to 0////; 0////; again 6eeping the decimal portions of the coordinates!

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0!= After the three warp points are set; select *mage/@<arp *mage from the Display menuto perform the warp! &M& "mage updates the image so that the defined points arepositioned at the warp locations! Select Save .ayer File from the File menu and save thewarped image as Imap!lyrJ!

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E=E2+*SE > // Source and 2eceiver Editing

This exercise demonstrates some of the editing tools available in MESA to change your surveys!Dou will import an image to use as a bac6ground! 7nce the survey is set up with the image asthe bac6ground; the receiver and source editing tools can be used to move points2 singularly; lineby line; or as a group! Creation and editing of exclusion Bones can also be aided by the use of

images in the bac6ground!

,!= Start MESA! &o to the .ayer Display?Options button submenu and select the .oad IGMG .ayer option! )oad the Iimage!lyrJ file that was created in &M& "mage in theprevious exercise!

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%!= Select Open Database from the File menu and open Iexercise/0J! )oaded imagesremain loaded when you open or close surveys! Dou can unload images by selecting'nload from the .ayer Display?Options button submenu! )oo6 at the first receiver line!There is a road on the image that runs near the first receiver! The road is at a differentangle than the receiver line! )et#s assume that you actually wanted the survey to beparallel to that road! Dou can use the 9ange earing tool to determine the difference in theangles! Dou can then use the Translation59otation tool to move the survey to the newposition!

3!= $ress the 2ange !earing tool button! "f you clic6 and hold down the )eft Mouse button;you can draw range bearing lines! old down the Ctrl 6ey when you draw the lines to snapthe start and end points of the line to the nearest records! oom in on the road a bit; clic6near the center of the road by the first receiver; and then drag and release the button in thecenter of the road further along! Dou should see that the bearing is about ,3,!*! olddown the Ctrl 6ey and clic6 on the first receiver! rag and release the button on anotherreceiver in the line! Dou should see that that the receiver line bearing is about ,34!+! Thismeans you need to ad?ust the survey by :8!, degrees to have the receiver lines parallel tothat road! $ress the 2ange !earing tool button again to turn off the tool! Select +lear Allfrom the button submenu to remove the lines from the display!

(!= Select (ranslation from the 'tilities menu! Choose Speci,y !oth in the +oordinate2otation section! $ut :8!, in the 2otation Angle box! Ma6e sure that both 2eceivers andSources are chec6ed and press O;! The survey should be rotated so that the firstreceiver line is parallel to the road!

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0!= @ow you want to redefine the third source line so that it follows the road that is displayedbehind it! Select Edit Sources from the Source Display?Options button submenu!Choose .ine Selection Mode and 2ede,ine .ine! Clic6 on the road where you want theline to start; and then clic6 out several points along the road! ouble clic6 to finish addingpoints and the source line will be redefined to follow the points you chose! Select EditSources again to exit Source Editing mode!

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*!= 'inally; the last seven receivers on the first receiver line are too close to the housingdevelopment! Dou will use the esign &rid; the Move command; and the Snap commandto accurately reposition those receivers! Select Edit 2eceivers from the 2eceiverDisplay?Options button submenu! $ress the Design Grid button! $ress Auto,it! Changethe grid siBes to 00 by 00! Chec6 Display Design Grid and press O;! ide the imagefrom the display in order to more easily see the design grid!

+!= Choose Group Selection Mode and Move! raw a polygon around the seven receiversand move the polygon to the intersections ?ust above the first source! ouble clic6 to placethe seven receivers!

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8!= Dou can now use the Snap function to position the receivers precisely! Choose 2ecordSelection Mode and Snap! Dou may have to use the Move function to get the receiverscloser to the correct intersections! Dou could also set the Snap Options so that thereceivers automatically snap to the nearest intersection after each move! Select Save As6e- Database from the File menu and save the survey as Iexercise/8J!

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E=E2+*SE >H // O,,set 4+ircular5 and 2ectangular Shooting

This exercise demonstrates the 7ffset <Circular= and 9ectangular shooting methods! 7ffset<Circular= and 9ectangular shooting are the easiest methods for shooting a survey! "n either case;the only thing that must be done is setting the offset ranges! All of the receivers that are within theoffset ranges for a source are added to the template for that source! These methods of shooting are

useful in areas with irregular receiver geometry!

,!= Start MESA and select Open from the File menu! 7pen the survey Iexercise/0J! $ressthe Shoot button on the Edit toolbar to open the IShootJ dialog!

%!= O,,set Shooting uses absolute offsets to determine the live receiver patch for a source!$ress the O,,set Options button to set the offsets! "f a Minimum O,,set is specified; thetemplate is ring shaped instead of simply circular! 'ill in the dialog as shown and press theO; button! $ress the Shoot button to actually shoot the survey! The esign Gindow willupdate to show each source being fired along with the template being used! .se the6eyboard shortcuts from page %( to speed up or pause the shooting!

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3!= Ghen shooting is finished; the next step should always be examing the templates thatwere created! Select Edit (emplates from the 'tilities menu! Ghile in (emplateSelection mode; left clic6 on a source to display the receiver patch for that source! All ofthe sources that fired into that patch will be highlighted! .se the arrow 6eys on the6eyboard to step through all of the templates! Ghen you are finished loo6ing at thetemplates; select Edit (emplates from the 'tilities menu again to exit the edit mode!

(!= $ress the Shoot button again! The template list is now filled with the templates createdby the 7ffset Shooting! e careful about removing templates from this list! "f a template isremoved without unshooting the survey; all of the sources still loo6 li6e they have beenfired; but some of the sources will no longer have associated receiver patches! $ress the'nshoot Survey button to return the sources to their unfired state! @ow that the survey isunfired; it is safe to press the Delete All button and remove all of those templates!

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0!= Select 2ectangular Shooting and press the 2ect Options button! This will open theI9ectangular 7ptionsJ dialog! 9ectangular Shooting wor6s li6e 7ffset Shooting but it usesa rectangular region around the source instead of a circular template! The !earingDimension is the length of the rectangle along the specified bearing! The +ross/!earingDimension is the length of the rectangle perpendicular to the specified bearing! Therectangle is centered around each source and all of the receivers within this area areincluded in the receiver patch for that source! 'ill in the dialog as shown and press O;!$ress the Shoot button to shoot the survey again! )oo6 at the resulting templates with Edit(emplates!

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*!= 9eturn to the IShootJ dialog; unshoot the survey; and delete all of the templates again!Select O,,set Shooting once more; but this time unchec6 the Fire All Sources option!$ress the Shoot button! "nstead of beginning to shoot the survey; MESA prompts you toselect a starting source! Clic6 on the source at %(+(%3*!%/; *0%33,+!*/! This is the ,3th source on the 3rd source line! $ress the Shoot button on the Edit toolbar to open theIAuto:Shoot )imitsJ dialog!

+!= The IAuto:Shoot )imitsJ dialog is used to specify a subset of the survey area for shooting!"n this case; the limits will only affect the sources! The receivers portion is used to limit rollon5off with other shooting methods! The values in the edit boxes correspond to MESAslogical ordering of sources and receivers and not the point label numbering! 'ill in thesource limits as shown and push the Shoot button! Shooting will then commence for thespecified area! The survey should appear as shown!

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E=E2+*SE >1 // Automatic (emplate +entering

This exercise demonstrates the Automatic Template Centering shooting method! AutomaticTemplate Centering is the most commonly used shooting method in MESA! 'or this method; theclosest receiver to a source point is located and used as a centering point for the entire template!"t is also possible to s6ew the template from the center by using the Template S6ewing ialog!

S6ewing can be used to perform off:end shooting geometries!

,!= Start MESA; if necessary; and select Open from the File menu! 7pen the survey IbasicJ!$ress the Shoot button to open the Shoot dialog!

%!= A template must be defined to use Automatic Template Centering! $ress the +reate(emplate button! The template defines the siBe of the receiver patch that is active for

shooting! "n Automatic Template Centering; this template is centered around each source!'ill in the 6umber o, .ines and 2eceivers Per .ine values as shown and press O;! Thetemplate should be automatically selected in the template list and Automatic (emplate+entering should be the selected shooting method! Ferify that the (emplate 2oll On?O,,and Fire All Sources options are both chec6ed! $ress the Shoot button to shoot thesurvey!

3!= Select Edit (emplates from the 'tilities menu and loo6 at the shooting results! ecausethis survey is idealiBed and has the sources perpendicular to the receiver lines; all of thesources in a line between two receiver lines have the same centering position; so they areall fired into the same receiver patch! "f the sources did not line up; they would havedifferent receiver patches!

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(!= "t is also possible to s6ew the template so that the sources are not in the center of it! &obac6 into the Shoot dialog and unshoot the survey! $ress the Auto+enter Options button!The resulting dialog is used to specify the s6ew in terms of number of receivers andnumber of receiver lines! 'ill it in as shown; press O;; press Shoot; and then loo6 at theresults in the Edit (emplates mode!

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0!= "n both of the previous shooting cases; the receiver patch has rolled on and off the edgeof the survey! The amount of roll on5off can be changed if necessary! .nshoot the surveyand reset the s6ew parameters to / and /! .nchec6 the (emplate 2oll On?O,, option andpress Shoot! MESA brings up the Auto:Shoot )imits dialog! This dialog is used to set theranges where the receiver patch stops rolling! $ress the Survey Edges button to fill in thedialog with the full extents of the survey! This will cause the receiver patch to stop rollingwhen it reaches the edges of the survey! $ress the Shoot button to shoot the survey!

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*!= $ress the Open Database button and load the Iexercise/(J survey! .sing the templatefrom the Design Guide; shoot this survey with Automatic (emplate +entering; ma6ingsure to Fire All Sources and 2oll (emplate On?O,, ! )oo6 at the results in the Edit(emplates mode! The template loo6s good in the lower half of the survey; but it is notcorrect in the upper half! The problem is that the template is positioned by using theinternal se-uential numbering! Since the starting position of the receiver lines changes; these-uentially numbered receivers do not line up! There would be a similar problem if therewere gaps of missing receivers in the middle of the lines! The full number of receivers foreach line would still be in the template regardless of the gaps! The position of the lastreceiver on each receiver line will not affect the template positioning if the template is rollingoff the survey!

+!= The Shooting Grid option is used to correct the template positioning in surveys withirregular starting postions or gaps in the middle of receiver lines! 9eturn to the Shootdialog and unshoot the survey! Select Automatic (emplate +entering as the shootingmethod and toggle on the option to 'se Shooting Grid at the lower right! The ShootingGrid option will impose a grid on the receivers which will compensate for the irregularshape of the survey!

The shooting grid should automatically have default values that will wor6 well for the survey!"t is also possible to manually define the shooting grid for greater control! Clic6 on the Gridbutton to open the Shooting &rid dialog! $ress the Auto Fit button to set the values in thedialog as shown! $ress the O; button to close the dialog; and then press the Shoot buttonto shoot the survey! )oo6 at the results in Edit (emplates mode! The receiver templatesshould be the same throughout the entire survey area!

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90



E=E2+*SE >11 // Salvo Shooting

This exercise shows the Salvo shooting method! Salvo shooting handles scenarios of multi:source salvos that span receiver lines and salvos that re-uire restricting the inline template roll!Salvo shooting is very well suited for slant geometries and bottom:cable designs! "n ourterminology; a salvo is a set of source points <in a single source line= that is located between two

receiver lines! 7ne source point or twenty source points can represent a salvo; depending on thelayout of the survey!

,!= Start MESA; if necessary; and select Open from the File menu! 7pen the surveyIexercise/%YslantJ! $ress the Shoot button to open the IShootJ dialog!

%!= Create a ,/H+% template and use Salvo Shooting! $ress Shoot to set the salvos! Clic6on a source in the center of the survey area! Salvo shooting ta6es all of the sources onthat line between two receiver lines and shoots them into the same template! Dou canselect several salvos and the receiver template will automatically ad?ust to be centeredbetween all of the selected salvos! Clic6 on a salvo again to remove it from the template!Experiment for a bit with selecting salvos to see how the template changes! 'or thisexample; ?ust select one salvo for the template!

3!= The template is centered around the selected salvos by default! "t is also possible tos6ew the template so that it is no longer centered! $ress the arrow 6eys on the 6eyboard tomove the template around! The green instruction bar at the bottom of the esign Gindowwill update with the amount of s6ew in terms of receivers and lines! Try moving thetemplate around! 9eturn the template to the original; centered position when finished!

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(!= .nselect the Shoot icon to finish selecting salvos and to open the ISalvo 9ollJ dialog!The roll parameters are used to specify which sources are fired! A value of % for Source.ine 2oll would fire every other line of sources; starting with the selected sources! A valueof % for 2eceiver .ine 2oll would fire every other row of sources; again starting with theselected sources! The default values of , and , shoot the entire survey! The Auto:Shoot)imits wor6 the same as in the other shooting methods and can be used to further limit thesources and receivers used! 'or this example; use the defaults of , and , and do not setand Auto:Shoot )imits! $ress Shoot to shoot the survey!

0!= As always when shooting; examine the results with Edit (emplates from the 'tilities menu!

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E=E2+*SE >1& // .abel Shooting

This exercise demonstrates the )abel Shooting method! )abel Shooting shoots surveys usingthe labeling numbers; not the internal numbering! "t is convenient for shooting geometries whichhave a large number of sources shooting into a receiver patch <bottom cable surveys; forexample=!

,!= Start MESA; if necessary; and select Open from the File menu! 7pen the survey IbasicJ!efore using )abel Shooting; it is very important to 6now the numbering scheme of thesurvey and to 6now the numbers of the initial template location! "n this case; a template inthe bottom left corner of the survey area will be used for the initial setup! The template willuse sources (///0 to (///8 and receivers ,///% to ,//%0; %///% to %//%0; 3///% to3//%0; and (///% to (//%0!

%!= $ress the Shoot button on the Edit toolbar! .nshoot the survey and delete all of thetemplates; if necessary! $ress the +reate (emplate button and ma6e a template of ( linesby %( receivers per line! Select .abel Shooting and press the Shoot button! This willopen the I)abel @umber ShootingJ dialog!

3!= The J)abel @umber ShootingJ dialog has two parts! The spreadsheet is used to specify

the initial template and also to display the updated positions as the template rolls! The 2ollParameters section is used to control how the template rolls! 'ill in the templatespreadsheet with the values from step , for the initial template! As the 'rom and Tocolumns are filled; the esign Gindow updates to show the specified sources andreceivers! Ghen finished; the esign Gindow should appear as shown!

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(!= After the initial template is correctly entered into the spreadsheet; the 2oll Parameters are used to roll the template! The values in the 2oll Parameters fields are added orsubtracted; depending on the direction of movement; from the numbers in the spreadsheet!"f the new values correspond to numbers in the survey; those sources and receivers areused for the new template! "f the numbers do not correspond; the process is repeated!This occurs until the entire survey has been shot! The Previe- buttons are used to chec6the 2oll Parameters! $ress the 'p Arro- button and observe the results to thespreadsheet and in the esign Gindow!

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0!= 7bviously the default roll parameters are not going to wor6 in this case! The sources shiftby , location and the receivers shift by , line! 9ecall that the numbering scheme for thissurvey has the numbering increase by , in the inline direction for the sources and by *///in the crossline direction for the receivers! 'or this template; the roll should move thetemplate up to the next group of ( sources and ?ust , receiver line up! 7nly the originaltemplate can be edited; press the ome button to return to it and then change the SourcePoints to (! )eave the 2ec .ine 2oll as ,////; since this is correct! $ress the 'p Arro-button again to observe the change!

*!= $ress the ome button again to return to the first template position! @ow try pressing the2ight Arro- button! Again the default parameters are not correct! This time the templateneeds to move crossline with regards to the sources and inline with regards to thereceivers! The numbering for receivers increases by , inline and there are ( receiversbetween source lines! The number for sources increases by ,//// between source lines!"n this case; change the 2ec Points to ( and leave Source .ine 2oll as ,////! Thetemplate should now roll correctly when you press the 2ight Arro- button! "t is a goodidea to roll the template several times in the different directions to chec6 that everything isset correctly!

+!= The 'se source limits option can be used to specify the sources to shoot instead ofsimply shooting the entire survey! "n this case; leave the 'se source limits optionunchec6ed and press the Shoot button to shoot the survey! As always; examine the resultswith Edit (emplates from the 'tilities menu!

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DO IT YOURSELF #12

7pen the Iexercise/%YregularJ survey! Try to shoot this survey with label shooting! The templateshould have ( lines of receivers and 3% receivers per line! There will be * sources in eachtemplate! Ghen you have finished shooting the survey; loo6 at the results with Edit (emplatesfrom the 'tilities menu! The templates should appear as shown!

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E=E2+*SE >1) // Multi/Survey +apability

This exercise shows how to load multiple surveys in one MESA session! "n areas where existing3: survey information exists; you can import those surveys and build designs that merge orBipper your current survey designs with the pre:existing ones!

Dou will be importing two 3: surveys for exercise 1,3! The surveys are Imulti,J; which wascreated in the Io "t DourselfJ section of Exercise 1,; and Imulti%J; which was created in Exercise13! After importing both surveys; you will calculate three fold plots2 a plot showing the new foldfor multi,; a plot of the new fold for multi%; and a combined fold plot for both multi, and multi%!

,!= Start MESA; if necessary and Open Database from the File menu! 7pen the survey youcreated in Exercise 1, called multi,! Fiew the fold by pressing the Fold Graph icon toma6e sure that all the fold calculations still exist!

%!= &o bac6 to the File menu; select the Multi Database option; and under this option select.oad! 'nload and Select will become active once multiple surveys are loaded in theesign Gindow! 7pen the survey you created in Exercise 13 called multi %! Dour esign

Gindow should loo6 li6e the following!

3!= @otice that the title of the active survey is in the esign Gindow title bar! 9ight now theactive survey is multi,! "f you display the fold now; it will show you the fold plot for multi,!)eave the fold displayed in the design window! .nder the File menu; select the MultiDatabase option again and choose Select! This will bring up the ISelect atabaseJ dialogthat allows you to choose which of the loaded databases is active! Choose multi% andselect O;! The esign Gindow is now showing both geometries but only the fold of multi%!

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The idea of having a multiple database survey is to show how the attributes of one surveywill affect the other!

(!= 'irst you will loo6 at how multi% will affect the fold of multi,! Ma6e multi, the activedatabase again! 7pen the Display !ins button submenu and select !in Grid Settings toopen the Iin efinitionJ dialog! @otice that the Fit (o Multiple Databases chec6 box isnow active! 'or this calculation though; you only want the bin grid to cover the activesurvey; so leave the Fit to Multiple Databases option unchec6ed! $ress the Auto Fitbutton and then press O;! Fiew the new bin grid in the esign Gindow to chec6 that thebins only cover the multi, survey!

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0!= 7nce your esign Gindow appears as above; open the !in Analysis menu and choosethe Fold +alculation option! "n this window select Fold7 O,,sets7 and A#imuths in theCalculation 7ptions section! "n order to calculate the fold with the influence of multi%; youmust create a named calculation! Chec6 the 6amed Fold +alculation chec6 box <MESAwill give the calculation a default name= and that will activate the option to 'se MultipleDatabases! Chec6 this option as well and press O;! The fold in the esign Gindow willnow show the original fold throughout the ma?ority of the survey and the increased foldwhere multi, and multi% overlap! The display below shows the fold without the sources and

receivers displayed for a clearer view!

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*!= o the same procedure now for multi%! .nselect the Fold Graph icon to remove the foldplot from the display! .nder the File menu; select Multi Database and choose the Selectoption! Ma6e multi% the active survey! Select !in Grid Settings from the Display !ins button submenu and in the Iin efinitionJ dialog perform another Auto Fit; this time formulti%! Do not toggle on the Fit to Multiple Databases checkbox! Select O; and displaythe bins in the esign Gindow! The esign Gindow should be similar to the window below!

+!= 7pen the !in Analysis menu and choose the Fold +alculation option! "n this dialogselect Fold7 O,,sets7 and A#imuths for the Calculation 7ptions! "n order to calculate thefold with the influence of multi,; you must create a named calculation! Chec6 the 6amedFold +alculation chec6 box <MESA will give the calculation a default name= and that willactivate the option to 'se Multiple Databases! Chec6 this option as well and press O;!The fold in the design window will now show the original fold throughout the ma?ority of thesurvey and the increased fold where multi, and multi% overlap! The display below showsthe fold without the sources and receivers displayed for a clearer view!

8!= MESA can also calculate the fold for the entire multi database area including the overlapregion between multi, and multi%! 7pen the Display !ins button submenu and select !inGrid Settings! "n the in efinition dialog; chec6 the Fit to Multiple Databases option!

After chec6ing this option; press Auto Fit and select O;! The esign Gindow shouldappear as below!

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4!= 7pen the !in Analysis menu and choose the Fold +alculation option! "n this dialogselect Fold7 O,,sets7 and A#imuths for the Calculation 7ptions! "n order to calculate thetotal fold for multi, and multi%; you must create a named calculation! Chec6 the 6amedFold +alculation chec6 box <MESA will give the calculation a default name= and that willactivate the option to 'se Multiple Databases! Chec6 this option as well and press O;!The fold in the design window will now show the original fold throughout the ma?ority of thesurveys and the increased fold where multi, and multi% overlap! The display below shows

the fold without the sources and receivers displayed for a clearer view!

DO IT YOURSELF #13

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Ma6e multi, the active database! 9edefine the bin grid so that it does not use multipledatabases! Select Fold Deletion from the !in Analysis menu and Delete All of the named foldcalculations that you created!

@ow create two new named fold calculations2 one that uses ?ust multi, and one that uses multi,and multi%!

Select Fold +ompare from the !in Analysis menu! 'old compare creates a color plot of thedifference between two fold calculations! Compare the fold for multi, and multi% with the fold for

?ust multi,!

Toggle on the Fold Graph button to display the difference plot! @ow you can see exactly howmuch fold is added by the overlap area! The fold comparison is also very useful for comparing anideal survey plan against the actual production data! This will be demonstrated in a laterexercise!

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E=E2+*SE >1 // 'sing Advisor

This exercise demonstrates some of the functionality of the Advisor menu! This menu is notavailable in MESA 'ield!

,!= 'rom the File menu; select the Open Database option and open multi,!mas!

%!= 'rom the Advisor menu; choose the Aperture Modeling option! The following toolbar willappear2

3!= Select the Add Model (arget icon and clic6 on the survey to position a target! The targetposition can be ad?usted in the parameters dialog to precisely place the target! After youclic6 on the survey; the ITarget $arametersJ dialog will appear! Set the parameters aspictured! Ghen you clic6 O;; the target will be displayed as a red s-uare in the esignGindow! Clic6 on the survey and add a second target with the pictured parameters!

(!= @ext; select the Add Segment button and clic6 on the active target <the second target= to

add a segment to define the shape of the target region by specifying the depth; dip; andaBimuth of the dip! After setting up the first segment; clic6 again to create a secondsegment!

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0!= @ow you need to add segments to the first target as well! Dou need to ma6e the first targetthe active target to add segments to it! $ress the Select (arget button and then clic6 onthe first target! Select the Add Segment icon again and define two segments for thetarget!

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*!= Dour esign Gindow should now loo6 li6e this2

The blue outline defines the full:fold migration aperture! "n other words; you need to havefull fold in this region if you desire to ade-uately image your target region!

+!= $lotting the fold in the design window indicates that this region extends out of the full foldarea! Dou would need to extend the survey to the east to fully image the target area in thiscase!

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E=E2+*SE >1B // Attributes and Filtering

This exercise demonstrates how to add attributes to a survey and how to filter a survey based onthose attributes! Attributes can be integers or floating point numbers and are associated witheither receivers or sources! The only limit to the number of attributes that you can add to asurvey is the amount of physical memory <9AM= on your machine! 'ilters allow you to define

subsets of source and receiver points within your survey design! y filtering based on attributevalues; you can design very complicated surveys that span ac-uisition environments and usemultiple types of e-uipment!

Dou will be creating a generic transition Bone survey in this example! $art of the survey area willbe declared water with an attribute! Dou will then shoot the survey with two different templates for the water or land areas!

,!= Select Open Database from the File menu and load Ifullfold!masJ; the survey you created ino "t Dourself 10! 7pen the Edit Exclusions toolbar!

%!= Choose the Polygon icon to create a regular polygon Bone! Create a polygon with the

following coordinates2

<*3*,%/; ,*4*8//=; <*3*,%/; ,**4/+/=; <*(4///; ,**4/+/=; <*(4///; ,*4*8//=

The polygon should be displayed on the survey2

3!= Dou are now ready to start adding attributes to the survey! Select Add?2emove Attributes from the Attribute 3isibility and Options button submenu!

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(!= @otice the tabs in this dialog! Dou can create attributes for either sources or receivers byselecting the appropriate tab! 'irst; create a source attribute! $ress the Add button! Thisopens the IAdd AttributeJ dialog! Dou give the attribute a name and choose its type in thisdialog! @ame the attribute IwaterJ and ma6e it an integer! $ress O;! The attribute will belisted in the source attributes! @ow switch to the 2eceiver Attributes tab and create thesame attribute for the receivers!

0!= $ress O; to return to the esign Gindow! Dou have now added an attribute to the sourcesand the receivers! Dou still need to assign values to the attributeV this can be accomplishedin several different ways! Dou can use the "mport Gindow to import values from an ASC""file; manually enter values in the spreadsheets; identify a point <hold down the Shift 6ey and)eft:Clic6 on it= and manually enter the value; set all sources or receivers in an exclusionBone to the same value; and use the Edit toolbars to assign values to single points; lines ofpoints; or groups of points! "n this exercise; you will be assigning values with thespreadsheets and the exclusion Bone tool!

*!= Select 2eceiver Spreadsheet from the .ayout menu! Dou will want to assign a value of , toevery receiver that is East of H Coordinate *3*,%/!//! )eft:Clic6 on a cell in the HCoordinate column to highlight it! 9ight:Clic6 on the cell to open the edit menu and selectSort! Dou want to sort the spreadsheet so that the H Coordinates are ascending! Dou donot need to set a secondary sort 6ey! $ress O; in the ISortJ dialog to sort the spreadsheetinto ascending H Coordinate order!

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+!= Scroll down through the spreadsheet until you find the H Coordinates larger than *3*,%/ <thefirst one should be at line 3343 in the spreadsheet=! Scroll over to the water column andput a , in the water cell for that row! Clic6 on a different cell and clic6 bac6 on the water cellto highlight it again! Scroll to the very end of the spreadsheet; hold down the Shift 6ey; andleft clic6 on the last cell in the water column! This will highlight all of the cells in the watercolumn between the cell you ?ust edited and the end of the spreadsheet! 9ight:Clic6 on thehighlighted cells and select Fill from the menu! 'ill the range with an increment of /! All ofthe receivers that are East of *3*,%/ should now have a water value of ,! Close thespreadsheet!

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8!= @ow you need to set the attribute value for the sources! Dou will use the exclusion Bone toolto do this! Select Edit Sources from the Source Display?Options button submenu! Thisopens the Edit Sources toolbar! $ress the Exclusion Attribute Mode button!

4!= The first time you press this button; the IExclusion 9ecord Attribute SettingsJ dialog opens!Dou use this dialog to define the attribute and the value to give it! Dou also choose to setthe value either by manually selecting exclusion Bones or by automatically setting the valuefor all exclusion Bones in a layer! Choose the option to Select Exclusions Manually; findwater in the Attribute list; and set the 3alue to ,! $ress O; to go to the esign Gindow toselect the exclusion Bone! Clic6 on the exclusion Bone that you defined! The exclusionshould -uic6ly flash to indicate that it was selected and that all of the sources in the Bonenow have a water attribute of ,! Dou can now ma6e a filter to chec6 the attribute settings!Select Edit Sources from the Source Display?Options button submenu to exit sourceediting mode!

,/!=Select Filter Options from the 2ecord Filter and Filter Options button submenu! The filterdialog defines what sources and receivers are displayed! Dou construct a filter bycombining comparison statements! Any source or receiver that passes the filter settings isdisplayedV all of the other sources or receivers are hidden from the display! 7nly the visiblesources and receivers are used for any program functions! Shooting; bin attributecalculations; data output; statistics; etc! only use the unfiltered points! This feature providestremendous flexibility; particularly on complicated survey designs with different shootingtemplates; different 6inds of the e-uipment; and different terrains!

,,!=Dou want to filter the survey to show you ?ust the sources and receivers that have a watervalue of ,! This way you can chec6 that all of the points in the exclusion Bone wereupdated correctly! 'or the Source Filters; find water in the list of items to filter; choose *sE9ual (o from the comparison statements list; and put a value of , in the value box! $ressthe Add button to add the statement to the filter list! Dou could continue to add statementsto the filter list to ma6e a more complex filter! "f you select logical A6D ,ilters; all of thestatements have to be true for the source to be displayed! Select logical O2 ,ilters todisplay sources that are true for any of the statements in the list!

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,%!=Switch to the 2eceiver Filters tab and create the same comparison statement! The receiverand source filters are entirely independent; so you can have completely different filteringcriteria for your sources and receivers! $ress O; once you have the filters set!

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,3!=Toggle the 2ecord Filter and Filter Options button in the esign Gindow to apply orremove the filter! @otice that the filter parameters are displayed in the legend so that youcan see exactly what is being displayed! Dou should only have the sources and receiversin the exclusion Bone displayed when the filter is applied!

,(!=9eturn to the filter dialog and switch the filter settings! Change the comparison to 6O(E:'A.S and press the 'pdate button! This will update the statement in the list with thenew comparison! Dou can also 2emove the existing statement and Add a new one!Change both the source filter and the receiver filter to water 6O( E:'A.S ,!

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,0!=Dou can now use the filtered survey to shoot a template that changes as it rolls into thefiltered area! "n Exercise 13; you shot this survey with a ,/ by *( template! Dou want touse this template again on the displayed part; but you will use a different template for thewater points! Assume you do not want the ,/ by *( template to use the water points!$ress the Shoot button!

,*!=Create a ,/ line by *( receivers per line template! Choose Automatic (emplate +entering and press Shoot to shoot the survey! Toggle off the filter so that the entire survey isdisplayed and chec6 your templates with Edit (emplates from the 'tilities menu! @oticethat only the displayed sources were fired and that the templates only use the displayedreceivers!

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,+!=@ow you want to shoot the water sources! Assume that you want to use the non waterreceivers in the templates for the water sources! Additionally assume that you want to have( receiver lines live in the water; but ,/ lines live on land! .pdate the source filter so thatwater E:'A.S ,; but leave the receiver filter as it is! Toggle the filter on!

,8!= $ress the Shoot button! Choose the ,/x*( template and Automatic (emplate +enteringagain! Chec6 the 'se .ine Filters option and press the .ine Filters button! The I)ine'ilteringJ dialog allows you to honor or override the filtering for each line in a template! Alllines honor filtering by default! Since you want to have ( lines live in the water area; youneed to choose segments (; 0; *; and + and set each of them to override the filter settings!$ress O; in the I)ine 'ilteringJ dialog and press Shoot to shoot the water sources!

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,4!=Turn off the filter and loo6 at the templates with Edit (emplates again! @otice that the watersources have templates with ,/ lines of non:water receivers and ( lines of water ones!Save the changes to the database!

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DO IT YOURSELF #15

Try several different operations with the filter on and off to see the differences! Turn the filter onand loo6 at the .and Survey Statistics or perform +ost Analysis! @ow try them with the filteroff!

.nshoot the land portion of the survey without affecting the water sources <filter the survey sothat only the land sources are displayed=! @ow try to shoot the land again with the ,/ x *(template! This time have two receiver lines live at the bottom of the template in the water sectionof the survey! .se Edit (emplates to loo6 at the results2

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E=E2+*SE >1C // Displaying Data

This exercise shows how to display different types of data in MESA! Dou will be using secondarycoordinates; fold difference plots; and attribute plots!

,!= Select Open Database from the File menu and load Ifullfold!masJ; the survey you used in

Exercise 1,0! The water attribute should still be set for the part of the survey in the exclusionBone!

%!= 'irst; you want to use the secondary coordinates feature to store the initial surveycoordinates! Every source and receiver point now has a primary H; D and; coordinate anda secondary H; D; and coordinate associated with it! The primary coordinate is thedisplayed coordinate! The secondary coordinate simply allows you to store anothercoordinate position for each point! Dou can use the secondary coordinate to store the initialidealiBed survey coordinates; and have the actual real world positions in the primarycoordinates! Dou can then swap the two positions to see the differences!

3!= Select Secondary +oordinates from the 'tilities menu! This opens the ISecondaryCoordinates 7ptionsJ dialog! This dialog is used to change or update the coordinates!

Choose Store Primary +oordinates as Secondary +oordinates! This feature copies theprimary coordinates into the secondary coordinates; essentially creating a bac6up copy of theprimary coordinates! Dou want to store !oth 2eceiver and Source +oordinates! $ress O;to store the coordinates!

@ow that you have stored the coordinates; you can 2estore Primary +oordinates ,romSecondary +oordinates to copy the secondary coordinates bac6 into the primarycoordinates! Dou can also S-ap Primary and Secondary +oordinates to simply swapthe primary and secondary coordinates without overwriting each other! Select +hangeDisplay Options to activate the Display +oordinate Di,,erence 3ectors option! Ghenthis option is chec6ed; vectors are drawn in the esign Gindow to show the difference inposition between the primary and secondary coordinates!

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(!= Select 2andomi#er from the 'tilities menu! This function randomiBes the positions ofsources and receivers by moving them to a random point within a limited distance fromtheir original position! Set the options in the I9andomiBe CoordinatesJ dialog as shown!This can be used to simulate the randomness of a real world survey!

0!= 7pen the ISecondary Coordinates 7ptionsJ dialog again! Select +hange Display Options

and then chec6 Display +oordinate Di,,erence 3ectors! The Minimum Di,,erence toDisplay field lets you limit the vectors that are displayed! MESA will only display vectorsthat are larger than the minimum you specify! So if you only want to see vectors for pointsthat moved more than %0 units; put a %0 in for the minimum difference! 'or now; simplyleave the minimum as /; this will display vectors for every point! $ress O; and Boom in onthe esign Gindow! Dou will see the vectors displayedV the end of the vector is the positionof the secondary coordinate for that point!

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*!= Try swapping the primary and secondary coordinates a few times! Dou might try swapping ?ust sources or ?ust receivers as well! 'inish by swapping the original idealiBed survey bac6into the primary coordinates! Turn off the vector display by unchec6ing the Display+oordinate Di,,erence 3ectors option!

+!= efine a ,,/ by ,,/ bin grid for the survey! Select Fold +alculation from the !in Analysis

menu! Calculate Fold7 O,,sets7 and A#imuths to a named fold calculation titled Ifullfold Oideal O 'ull ataJ!

8!= Swap the primary and secondary coordinates again so that the randomiBed survey isdisplayed! Select Fold +alculation and create a named fold calculation titled Ifullfold O

random O 'ull ataJ!

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4!= @ow you can compare the two named fold calculations to generate a fold difference plot! Thefold difference plot lets you easily see areas where the randomiBed survey positions greatlychange the fold distribution! Select Fold +ompare from the !in Analysis menu! CompareIfullfold O random O 'ull ataJ to Ifullfold O ideal O 'ull ataJ! @ame the fold difference plotI'old differenceJ! $ress O; to generate the fold difference plot!

,/!=Toggle the Fold Graph button on to display the fold difference plot in the esign Gindow!Dou may need to Boom in and toggle off the display of the sources and receivers to bettersee the difference plot! Dou can switch to a different fold calculation to display by using theFold Selection option in the !in Analysis menu! Ghen you are done loo6ing at the folddisplays; swap the ideal coordinates bac6 into the primary coordinates!

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,,!=Attributes can be displayed in the esign Gindow with color plots as well! 7pen the2eceiver Spreadsheet from the .ayout menu! )eft:Clic6 on the Coordinate columnheader to highlight the entire column! 9ight:Clic6 on the highlighted cells to open the editmenu and select Formula!

,%!=Dou can use the I'ormulaJ dialog to fill cells in the spreadsheet with information from other

cells! "n this case; you want to create a Coordinate by subtracting off a large portion ofthe H Coordinate! Select H Coordinate from the Database 3ariables list! "t will beautomatically added to the Formula! $ress the I button and then choose Secondary Hfrom the list! This will subtract each row#s $rimary and Secondary H Coordinates and thenthe result of this calculation will be put into the Coordinate cell!

120



,3!=@ow you can display the color plot for Elevation in the esign Gindow! Close the 9eceiverSpreadsheet! Select Attribute Display from the Attribute 3isibility and Options buttonsubmenu! The IAttribute isplayJ dialog is used to choose the attributes to display! Doucan display a source attribute; a receiver attribute; or both! 'or this example; leave thesource attribute as @one and set the receiver attribute to Elevation! $ress O;!

,(!=$ress the Attribute 3isibility and Options button to display the receiver attribute color plotnow!

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DO IT YOURSELF #16

"t is now possible to define different symbols for different instrument types! 7pen Ifullfold!masJand select Edit 2eceivers from the 2eceiver Display?Options button submenu! Choose groupselection mode; select *nstrument from the list box; and then clic6 out a box around some of theland receivers!

"n the Iefine "nstrumentJ dialog; choose new instrument from the list and add a multi componentphone 9, to the new instrument! Dou can display this new instrument with a different symbol bychec6ing the Override De,ault Symbol option! Chec6 this option and choose a different symbolfor the new instrument! $ress O; to close the dialog! Select Edit 2eceivers again to exit theediting mode! Dou should now see the different symbols in the esign Gindow! @otice also thatthe legend has the instrument name listed for the new symbol!

Try creating some different instruments for sources and water receivers!

122



E=E2+*SE >1 // Overvie- o, 2ecent Features7 Part *

This exercise demonstrates several features from recent MESA releases and how they might beused to solve a variety of design and integration problems!

,!= 7pen MESA! "n addition to displaying raster images; contour files; and vector files; MESAnow supports the display of Shapefiles! Select Shape,ile Manager from the dropdown menuof the Shapefile display toggle button!

The Shapefile Manager window will appear! Shapefiles can be loaded as individual files or byselecting entire directories containing multiple Shapefiles! 'or this exercise; press the Add Files button and open IyampaYcanyon!shp!J The filename will appear in the Shapefiles O raw 7rderlistbox! Ghen you select a file in the listbox; additional controls for setting Fill Pattern7 Fill +olor7and Outline +olor appear in the window! 'or this example; leave the default settings intact!

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$ress the O; button to return to the esign Gindow! The Shapefile layer can be shown orhidden by pressing the Shapefile isplay toggle button!

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%!= 7pen the exclusion editing toolbar! $ress the 2ead Exclusion File button! 7penIyampaYcanyon!xclJ to load a set of previously defined exclusion Bones!

Ghen you are importing exclusions from another pro?ect; you will get prompted with anotherdialog box which lists all the exclusions Bone in the file! Dou have the option of selecting a subsetof exclusions! This can be useful if you want to import boundaries or roads from an ad?oiningpro?ect but not all of the cultural features! 'or this example; we want to import all of the exclusionBones in the external file! y default; all of the Bones in the list should be selected! "f this is not

the case; press the Select All button! $ress to O; button to load all of the exclusions into thepro?ect!

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Exit the exclusion editing toolbar!

Dou should now see the exclusion Bones in the esign Gindow! "n this exercise; we are dealingwith an interesting area with multiple survey design challenges! There are several streams; a

126



large river; numerous historical sites; and a few bird nesting areas which are off limits forac-uisition e-uipment!

3!= )ay out an orthogonal survey! Select .ayout/@2eceivers/@.ines?!ric0s! 'ill out theparameters as shown below to create receiver lines with spacings ,,/ inline; 88/ crossline; /degrees inline bearing; and 4/ degrees crossline bearing! Also; select the Fill one optionand select the oundary layer and the Survey oundary exclusion Bone to fill! 9epeat theprocess for the source lines; but swap the bearings such that inline L 4/ degrees; crossline L/ degrees! Also; since we want to offset the source points; ma6e sure that =/Shi,t and J/Shi,t are set to 00 feet! 9efer to the following diagram for the parameters!

Dour survey should appear as shown in the following diagram! The diagram includes a Boom ofthe SG corner of the survey; showing that the sources lines are offset 00 feet inline and crossline

from the receiver lines! oom in on your survey to verify that you have the correct layout beforeproceeding!

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(!= Ghen you lay out source and receiver lines after defining exclusion Bone; the effects of theexclusion Bones are not automatically recalculated! 7pen the exclusion editing toolbar!

$ress the 2ecalculate E,,ects button! Dou will see all of the sources and receivers inside theexclusion Bones turn gray\which indicates the points are now dead! Exit the exclusion editingtoolbar!

Save your database as Iyampa,+J before proceeding!

0!= "n the next phase of this exercise; we will review some of the tools for analyBing how much ofour survey is affected by the obstacles in our design area! To do this; we will use the sourceand receiver attributes feature! Select Add?2emove Attributes from the attribute drop downmenu!

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$ress the Add button and add an integer source attribute named IobstructionsJ!

9epeat the process and create an integer receiver attribute named IobstructionsJ!

*!= y default; attribute data are initialiBed with a null# value! As a review of spreadsheetfunctionality; select .ayout/@2eceiver Spreadsheet! Scroll the spreadsheet horiBontallyuntil you can see the IobstructionsJ column! Enter a value of Bero in the first row! Clic6 theleft mouse button on the column title <obstructions= to select all of the cells in the column!Clic6 the right mouse button and select Fill from the menu! Select Fill 2ange and enter an

*ncrement of Bero to fill the entire obstructions column with Beroes!

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Close the receiver spreadsheet! Select .ayout/@Source Spreadsheet and repeat the processwith the sources to initialiBe the obstructions# source attribute with Beroes! Close the sourcespreadsheet when you are finished!

+!= Ge are now going to use the exclusion Bones to assign source and receiver attributes for thevarious types of obstructions! Ge will use the following assignments2

Obstruction (ype Attribute 3alue

@o obstruction /9ivers ,

@esting Areas %

Archaeological Sites 3

Ge have already initialiBed a ma?ority of the sources and receivers with an attribute value of Bero<no obstruction=! 7pen the receiver editing toolbar! Select the Exclusion Attribute Mode button!

This will open the Exclusion 9ecord Attribute Settings dialog box! This interface allows you to setan attribute value for all of the receivers that fall inside a particular exclusion or inside any of theexclusions for a selected layer! "n this exercise; we are going to set values for entire exclusionlayers! 'ill out the parameters as shown in the following diagram2

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Select Set by Selected .ayers! Select 9ivers# from the .ayer list! Select obstructions# from theAttribute list! Set the attribute 3alue e-ual to ,! $ress the O; button to finish! The dialog boxwill close!

Ge need to repeat this process for nesting and archaeological sites! $ress the ExclusionsAttribute Settings button!

This will reopen the Exclusion 9ecord Attribute Settings dialog box! 'ill out the parameters asshown below to set the attribute value e-ual to % for the nesting areas! $ress O; to finish!

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9epeat the process a third time to set the attribute value for the archaeological sites! 'ill out theparameters as shown below! $ress O; when you are finished!

Exit the receiver editing toolbar! 7pen the source editing toolbar and repeat the exact sameprocess for the sources! Assign the same three attribute values for source obstructions that youassigned for receiver obstructions! Exit the source editing toolbar when you are finished!

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8!= Fiew the attribute data to verify that you have made the assignments properly! SelectAttribute Display from the attribute drop down menu!

Select obstructions# for the source and receiver attribute to display!

$ress the Attribute Display toggle button in the esign Gindow to view the attribute data! oomand scroll around your survey to verify that the attributes have been assigned properly! The colorscale should range from /:3 with most of the sources and receivers showing an attribute value ofBero! Sources and receivers should have a value of one in the rivers; a value of two in the<purple= nesting areas; and a value of three in the <yellow= archaeological areas! "f your attributedata are not assigned properly; repeat this step of the exercise! Save your database again <samename= when your attribute data is correct!

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4!= There are several methods for analyBing attribute data! Ge have already been loo6ing atattributes in map view! Another method is to use the attribute histograms! Select 'tilities/@istogram <indo-! "n the &eometry istogram Settings dialog box; select the Sourceistogram radio button! Select obstructions# from the Attribute drop down list!

$ress the O; button to plot the histogram!

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'rom the plot; we can see that +8,( of our sources have a value of /!/ <no obstruction=! ,*( ofthe sources are in a river <obstruction value L ,=; ,*+ of the sources are in a nesting area<obstruction value L %=; and 34 of the sources are in an archaeological site obstruction value L 3=!Spend a moment examining the display options in this window! 'or example; press the (ogglePercent Display button to change the display to a percentage histogram!

$ress the istogram Settings button and change the display to a histogram of receiver attributedata!

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The percentages are similar for the receiver data!

Close the histogram window!

,/!= Another method for loo6ing at the distribution of attribute data is to use pie charts! Select'tilities/@Pie +hart <indo-! The $ie Chart Settings dialog box will appear! Dou can ma6epie charts from source attribute data; receiver attribute data; or bin5midpoint data! 'or thisexercise; select the Source Attributes radio button! Select obstructions# from the Attribute drop down list! Enter 7bstructions# in the (itle edit box!

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y default; the pie chart window will automatically divide the data into ranges! 'or this exercise;we will ta6e control over the plot settings! Select the Detailed +hart radio button! $ress the Add

button to define the first pie wedge in our chart! 'ill out the Chart etails parameters as follows!Since we are plotting integer data; set the value range from /!//:/!44!

$ress the Add button three more times to add three more pie wedge definitions! 'ill in theparameters as shown below!

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$ress O; in the $ie Chart Settings dialog box to create your chart!

To change the chart to receiver data; press the Pie +hart Settings button!

This will re:open the $ie Chart Settings dialog box! Select the 2eceiver Attributes radio buttonand select obstructions# from the Attribute drop down list! The detailed chart settings areretained from the previous chart; so you can simply press O; to plot the receiver data!

"ndividual pie charts can be saved as snapshots# and re:opened for comparison! Ghen youselect Save Snapshot from the drop down menu; you will be prompted to save your chart with auni-ue name!

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Call you snapshot I9eceiver 7bstructionsJ and press O;!

To recall a copy of your saved chart; select Open Snapshot from the drop down window! Select

9eceiver 7bstructions# from the list and your saved chart will open in a new window!

Snapshots can not be edited or modified; but are useful for comparison purposes! Close all ofyour pie chart windows before continuing with the exercise!

,,!= 7ne of the more time consuming aspects of designing a survey is adapting the sources andreceivers for culture and topography! "n this phase of the exercise; we are going use theautomatic repelling feature to move receivers outside of exclusion Bones! oom in on your

map on the western edge of the design so that you can see the large bend in the river andone of the <purple= nesting areas! The exact dimensions are not important; but see thefollowing diagram as a guide2

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The results of this feature will be easier to see if you first change the receiver symbols! SelectDisplay/@Options and change the receiver symbols from plus signs to another symbol; such asa solid circle! Also; change the IdeadJ color for receivers from light gray to orange and pressApply!

7pen the receiver editing toolbar! The first thing to do is to set up a grid for moving receiver

points! $ress the Design Grid Options button!

Ge need to set up an editing grid! $ress the Auto Fit button! @ext; change the *nline Spacing and +rossline Spacing to ,,/ feet if necessary! Ferify that the *nline !earing is set to /degrees! $ress the O; button when the settings are correct!

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)et#s say that you have some guidelines for moving receiver locations! $erhaps you will allowreceiver moves perpendicular to the receiver line in increments of ,,/ feet; but no move canexceed half of the receiver line spacing <,5% of 88/ feet L ((/ feet=! $ress the Exclusion2epulsion Mode button!

efore clic6ing anywhere in the esign Gindow; we need to set up our rules for moving receiverpoints! $ress the 2epelling Options button!

This will open the 9epelling 7ptions dialog box! The first tas6 is to set the rules for receivermovement in the Movement .imits group box! Since we are restricting our receiver movementto the crossline directions; select the +rossline radio button! Since we are restricting ourcrossline movement of receiver points to ((/ feet; set the Max Grid Points to ( <( grid lines ],,/ feet L ((/ feet=! Ma6e sure that the Max Grid Points for the inline direction is set to Bero!9efer to the following diagram for the parameters!

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There are two modes of exclusion repelling! Dou can manually clic6 on exclusion Bones; or youcan automatically repel from all exclusions in a given layer<s=! "nitially; we are going to usemanual mode! Select the Select Exclusions Manually radio button! $ress O; to start movingreceiver locations!

Do not rano!l" li$ "our !ouse in t%e Desi&n 'ino() Rea t%e *ollo(in& instrutionsare*ull" as "ou proee)

Ge are going to first move receivers located in the large river! Dou screen should appear asfollows2

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Clic6 the left mouse button *6S*DE the river! All of the receivers inside of this exclusion Bone willnow be moved in the crossline direction according to the rules we have set up! Dour screenshould now loo6 as follows2

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"f you loo6 at the orange receivers; you will see that they have been moved to grid nodes outsideof the river! "f you clic6 *6S*DE the river a second time; the process will be reversed and theorange receivers will be moved bac6 to their original positions! This is one of the few undo#functions in MESA! "f the movement rules do not produce the desired result; this gives you achance to refine the rules without ruining your survey! Please note (he undo ,unction only-or0s on the last exclusion #one you choose% Once you select another exclusion #one7you can not undo previous -or0%

)eave the river exclusion with the receivers repelled outside of the river! @ext; clic6 the leftmouse button on the <purple= nesting polygon south of the river! Dou should see the followingresult!

7nly the three receivers <noted in the red circle= were repelled from the exclusion Bone! ecausewe defined the movement rules to limit movement to a maximum of ( grid lines in the crosslinedirection; none of the other receivers in this exclusion Bone could be moved and they were left intheir original positions! Ge would have to change the rules if we want these receivers moved!

Assuming that our movement rules are acceptable; it can be time consuming to clic6 on exclusionBones one at a time! $ress the 2epelling Options button again! )eave the movement rules asthey were; but this time; select the 2epel From Select .ayers radio button! Ma6e sure that three

exclusions layers <9ivers; @esting; Archaeological Sites= are selected in the listbox! eforepressing the O; button; verify that your parameters are set as follows2

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After you press O;; all of the receivers that can be moved according to the rules will be moved!$an around the display to loo6 at the results of the repelling feature!

Exit receiver editing mode! To complete this phase of the exercise; return to Display/@Options and change the receiver dead color bac6 to light gray!

,%!= 9epelling the receiver locations does not automatically turn the receivers live! 7pen theexclusion editing toolbar and press the 2ecalculate E,,ects button! 9efer to step 1( of thisexercise if you don#t remember how to perform this function!

,3!= Dour survey design now has the receivers moved to accommodate the obstructions in thearea! Any receivers that had to be moved more than ((/ feet in the crossline direction haveare still dead! All of the source points are still in their pre:plot locations! )et#s loo6 at ourCM$ coverage for this design! $ress the Shoot button and define a ,* line by ,%8 receivertemplate! .se Automatic (emplate +entering with template roll on5off and shoot thesurvey! efine your bin grid with 00 x 00 feet bins and a line bearing of 4/ degrees! $erforma full 'old; 7ffset; and ABimuth fold calculation! isplay the fold map! "t should appear asfollows2

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As expect; we have some lower:fold holes to fill in due to our dead source locations!

,(!= Ge will perform the same exclusion repelling wor6flow on the sources <refer to step 1,, inthis exercise if necessary=! 7pen the source editing tool! efine a design grid for the sourcelocations! $ress the Auto Fit button! @ext; change the *nline Spacing and +rosslineSpacing to ,,/ feet if necessary! Ferify that the *nline !earing is set to 4/ degrees! $ressthe O; button when the settings are correct! 9efer to the following diagram!

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Ge will use similar guidelines for moving source locations! Ge will allow source movesperpendicular to the source line in increments of ,,/ feet; but no move can exceed half of thesource line spacing <,5% of 88/ feet L ((/ feet=! $ress the Exclusion 2epulsion Mode button!

efore clic6ing anywhere in the esign Gindow; we need to set up our rules for moving sourcepoints! $ress the 2epelling Options button!

Ge can use the same rules for source movement that we used for receivers! Select the

+rossline radio button! Set the Max Grid Points to ( <( grid lines ] ,,/ feet L ((/ feet=! Ma6esure that the Max Grid Points for the inline direction is set to Bero! Select the 2epel FromSelect .ayers radio button! Ma6e sure that three exclusions layers <9ivers; @esting; and

Archaeological Sites= are selected in the listbox!

As a final step; chec6 the Do 6ot Allo- Move *nto Selected Exclusions chec6box! This will6eep sources from moving out of one exclusion Bone into another exclusion Bone!

efore pressing the O; button; verify that your parameters are set as follows2

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Exit the source editing toolbar!

,0!= 9epelling the source locations does not automatically turn the sources live! 7pen theexclusion editing toolbar and press the 2ecalculate E,,ects button! 9efer to step 1( of this

exercise if you don#t remember how to perform this function!

After performing this calculation; a chec6 of the land survey statistics shows that there are8,8( total source points in your survey! 8,%/ sources are live and +8,( sources are fired!This means there are 3/* source points that have been moved outside of the exclusionBones and could now be fired <*( source points did not get moved due to our exclusionrepelling rules=!

,*!= There are various methods for shooting new source points that have been added to adesign! "n this case; we have 3/* sources that don#t have a template assignment! Ge needa method for easily shooting these additions without disturbing the template assignments forthe other source points! The best choice is to set up a source filter! Select Filter Options from the pull down menu!

Set up a source filter such that 'ired is 'A)SE A@ "s )ive is T9.E <refer to exercise 1,0=! Thefilter settings should appear as follows2

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$ress O; to exit filter definition! $ress the Filter button in the esign Gindow to apply thesource filter! Dour map should appear as shown in the following diagram2

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,+!= Gith the filter applied; we can now shoot the unfired sources without affecting the templateassignments for the rest of the source points! $ress the Shoot button! .se Automatic(emplate +entering <use the same ,*x,%8 template= with template roll on5off! Shoot theunfired sources! After the 3/* unfired sources have been fired; toggle off the filter!

,8!= 9ecalculate the fold; offsets; and aBimuths! isplay the fold map! Although the large

exclusion Bones still cause holes in the coverage; the addition of the 3/* source have helpedthe overall situation! Save your database <yampa,+= again at this point in the exercise!

,4!= There are several ways to loo6 at offset distribution data in MESA! Select !in Analysis/@Fold +rossplot from the main menu! The 'old Crossplot window will appear! The defaultdisplay shows the color:coded fold in discreet offset ranges for the first inline bin line!

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.se the arrow 6eys to step forward and bac6ward through the bin lines! $ress the !in .ine button to draw a line in the esign Gindow showing the current bin line! Dou can also directlytype in the bin line number into the edit box! Type ,8/# into the edit box and press KC9X!

Dou can see in the display that the large nesting exclusion Bone in the eastern half of the surveyis affecting the near offsets! A more dramatic way to see the missing offsets is to switch tohoriBontal slice mode! $ress the ori#ontal Slice button and step down to the ,0// feet offsetslice! The holes in offset coverage are very apparent!

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Switch bac6 to *nline !in mode! "n addition to loo6ing at coverage in the offset domain; you canalso use this window to visualiBe how mutes will affect your coverage! $ress the (ime Mode button and return to inline bin row ,8/! Dour screen should appear as follows2

The display is now showing the fold as a function of time! Since we don#t have any mutefunctions defined; the fold is constant for all time steps! Ge do see the same reduction in foldbetween bins 3//:((/ due to the missing near offsets!

$ress the Mute Functions button! The Mute 'unctions window will appear!

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$ress the First !rea0 Mute button <second from left=! A dialog box will appear for entering a firstbrea6 mute! Enter the following (ime?O,,set pair </ ms; / ft= and press the Add button! Entertwo more (ime?O,,set pairs <,/// ms; ,/// ft= and <%/// ms; (/// ft=! Dour mute functionshould appear as follows2

$ress the O; button! The mute function should now be displayed in the window!

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Close the mute function window! The mute will not be immediately applied to the data in the foldcrossplot! .se the arrow 6eys to step forward one bin line to see the mute applied to the fold plotfor inline bin line ,8, as shown below!

As expected; the missing offsets also manifest themselves as significant reductions in coveragewhen combined with a first brea6 mute! Spend a few moments analyBing the time domain foldcrossplot in the crossline and horiBontal slice domains! Close the fold crossplot before moving tothe next step in the exercise!

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%/!= "t is -uite common to test various template siBes and shapes during the design process! 'orsimple surveys; it is an easy matter to unshoot the survey and reshoot it with a differenttemplate! ut what about situations where the shooting was difficult or the templateinformation had to be imported and you don#t want to 6eep repeating the shooting process^ow do you 6eep multiple sets of template assignments in a single design pro?ect^ SelectShoot +on,iguration Manager from the drop down menu!

The Shoot Configuration Manager window will appear! The ,*x,%8 templates used during thispro?ect as stored as the shooting configuration named IefaultJ in the listbox!

)et#s say that we decide the long offsets in our original shooting template might not be necessaryand we want to reshoot the survey with circular templates instead! $ress the Add 6e- Shoot+on,ig button! Ghen prompted to enter a name for the new shooting configuration; enterICircularJ! The new entry will appear in the list box! Select Circular# from the list and press theO; button!

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This shooting configuration will now be applied to the survey! Since we haven#t shot the surveyyet for this configuration; all of the sources in the esign Gindow should have turned bac6 to their IunfiredJ color <blac6 by default=!

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$ress the Shoot button! efine circular templates with a /:+/// feet offset range and re:shootthe survey! After shooting is finished; select 'tilities/@Edit (emplates to verify the templateassignments!

Exit edit templates mode! $erform another fold calculation to see the results of this new shootingtemplate! "n the 'old Calculation dialog box; create a 6amed Fold +alculation and name the

result yampa,+ O circular#! See the following diagram for the parameters!

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)oo6 at the fold map in the esign Gindow!

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As expected; the coverage is similar to the rectangular templates; but the overall fold is lowersince we reduced the longer offsets! Select !in Analysis/@Fold +ompare! ifference theefault Mesa 'old Calculation# with yampa,+ O circular# and store the result in 'old difference#!9edisplay the fold map to show the difference map!

To change bac6 to the rectangular templates; re:open the Shoot +on,iguration Manager andselect the efaultJ templates again! 9eturn to 'tilities/@Edit (emplates and verify that theoriginal rectangular templates have been restored! Exit Edit Templates to continue the exercise!

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@ote2 'old calculations are not automatically tied to shooting configurations! Dou should usenamed fold calculations when using multiple shooting configurations\or you should recalculatethe fold every time you switch shooting configurations!

%,!= MESA can be used for functions beyond traditional survey design! "t can also be used forpre:plot vs! post plot comparison! "t can be used as a production trac6ing tool! "t can also be

used as a repository for auxiliary information related to the pro?ect! )et#s say you are usingMESA to 6eep trac6 of information gathered while scouting the pro?ect area! As we haveseen; there are some archaeological sites in this area! oom in on a particular polygonalarchaeological exclusion Bone <yellow= in the northern region of the pro?ect! See the followingmap!

Suppose this site is so sensitive that you need to provide special instructions that not only ise-uipment not allowed; foot and vehicle traffic from the crew is also prohibited! Dou can use the6ote feature to 6eep trac6 of these restrictions! Select +reate 6ote from the drop down menu!

@otes are tied to map locations! Clic6 the left mouse button inside of the yellow polygonexclusion Bone representing the archaeological site! The @ote dialog box will appear! @otesneed to have a uni-ue (opic and uni-ue text for the note! Dou also need to provide a +ategory for the note <used for searching=!

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Select K@ew CategoryX from the +ategory drop down list! Dou will be prompted for a categoryname! Enter AnasaBi#! $ress O;!

'ill in a (opic and additional text for the note! The following diagram shows an example of thetype of information you might store! 'or this exercise; it is not necessary to enter all of the notetext <but you need to enter something=! o not press O; yet!

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Along with the text for the note; you can also attach external files to the notes! $ress theAttachments button! The Manage Attachments dialog box will appear! $ress the Add button! "nthe Add Attachment dialog box that appears; press the Add File button! 7pen the fileyampaYarchYsite!?pg#! 'or the Attachment Description; enter photo of sunrise house#!

$ress O; to close the Add Attachment dialog box! The attached file will now be listed in theManage Attachments list box! $ress Done to close the Manage Attachments dialog box! $ressO; to close the @ote!

A default symbol <triangle= will now appear on the map! Dou are still in Create @ote# mode; soreturn to the @ote drop down menu and unchec6 +reate 6ote to exit this mode of operation!

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@otes are ob?ects that can be displayed and recalled! $ress the Pro8ect 6otes button in theesign Gindow to toggle the note display on and off! Select 6ote Settings from the drop downmenu to label the notes in the esign Gindow! Chec6 Sho- 6ote (opics and press O;!

Dou should now the label Sunrise ouse welling# attached to the note! To recall a note; changethe Find 2ecord settings to 6otes%

old down the KshiftX 6ey and clic6 the left mouse button on the symbol representing your note!The note will appear! $ress the Attachments button in the Manage Attachments dialog box!

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ouble:clic6 on the attachment <yampaYarchYsite;?pg= in the list box! "f you have file associationsfor _$E& files set up on your computer; the picture will automatically load in the assigned

application!

Dou may load any type of attachments into the note database! "f you store spreadsheets or textdocuments; those files will also auto:load if you have the file associations defined!

Close all of the note:related dialog boxes before continuing with the exercise!

%%!= The final steps in this exercise deal with some recently:added output formats that can assistin transferring your pro?ect to other mapping systems! Select Output/Shape,ile Output! Douwill be presented with a simple interface for exporting sources; receivers; and exclusionBones to a Shapefile!

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Select all three chec6boxes! $ress O;% Dou will be prompted for three file names! Accept thedefault file names <yampa,+Sources!shp; yampa,+9eceivers!shp; and yampa,+Exclusions!shp=!

To verify the output; open the Shape,ile Manager <refer to step 1, in this exercise=! $ress the

Add Files button and load the files yampa,+Sources!shp# and yampa,+9eceivers!shp#! $ressthe O; button to close the Shapefile Manager window! "n the esign Gindow; toggle off thesource and receiver display so you can see the sources and receivers from the Shapefile!

Ge use a default blac6 plus sign for our default symbol in the Shapefile output! "f you wish tochange the display; return to the Shape,ile Manager and change the symbol; siBe; and color forthe sources and receivers!

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%3!= MESA designs can also be output to >M format for use in the application &oogle Earth!Select Output/@;M Output! Dou will be prompted with the following interface!

Dou have the option of exporting source locations; receiver locations; exclusion Bones; the defaultfold map; and bac6ground raster images to the >M file! 'or this exercise; select Sources72eceivers7 and Exclusions!

ata in the >M file are stored in latitudes and longitudes; so you need to define a mappro?ection! $ress the +hange +oordinate System button! The Map $ro?ection dialog box willappear!

Set the Pro8ection to .S State $lane#! Set the one to C7 @ O /0/,#! Set the Datum?Ellipsoidto @A%+#! $ress O; to close this dialog box! The new coordinate system will appear in the

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>M 7utput dialog box! $ress O; to proceed! Ghen prompted; name the output fileJyampa,+!6mBJ!

"f you do not have &oogle Earth installed on your computer; the exercise is finished at this point!"f you have &oogle Earth on your computer; open a Gindows Explorer window and findyampa,+!6mB on your computer! ouble:clic6 on this file and the data will automatically load into&oogle Earth <provided you have the file associations set up=!

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Glossary o, (erms

!in The fundamental sub:surface sampling interval; typically ` the inline receiverspacing in width and ` the inline source spacing in height! Source:receivermidpoints that fall in this area are considered to be from the same commonmidpoint and contribute to the fold count!

!ox "n a regular orthogonal 3 survey this is defined by the area bounded by twoad?acent source lines and two ad?acent receiver lines and represents the smallestarea of a survey which defines all statistics!

+MP Common midpoint; or the point halfway between the source and receiver!

+MP bin A small s-uare or rectangular area often of width e-ual to half receiver spacing <9"=and length of half source spacing <S"=! All midpoints which lie inside this area belongto the same common midpoint; will be midpoint stac6ed and will therefore contributeto the fold!

+2P Common reflection point; or the point on a subsurface model horiBon that reflects

from a source to a receiver!

+ontour File &M&#s contour file format <!cyr=; which is created in &M& "mage from an ASC""file of H;D; and attribute values!

Exclusion A restrictive Bone within a survey! This can include areas where no sources;one receivers; and5or midpoint information can be recorded! Examples include wells;

pipelines; buildings; and rivers!

Fold The number of midpoints that fall within a CM$ bin! 'or simple surveys with s-uareor rectangular bins <S"5% by 9"5%=; 3 fold can be calculated from the inline and x:line fold as given by

inline fold L receiver line length 5 % source intervalx:line fold L number of receiver lines 5 %,old N inline ,old crossline ,old

'or an irregular survey with rectangular bins2

nominal ,old N 6umber o, sources?;m& 6umber channels bin si#e 4in ;m&5

Geo/ A procedure performed by &M& "mage which defines the coordinates for each2e,erencing pixel in a graphic image; based on the pixel scale of the image and the

coordinate of the upper left pixel of the image!

GMG *mage A utility program which is included with &reen Mountain &eophysics# softwarewhich geo:references and reformats graphics files< !tif and !dxf; for example= andcreates contoured files of attributes <surface or subsurface elevations; forexample=!

alo <also 6nown as Taper= Additional area of a survey re-uired to build up full fold!

.ayer File &M&#s image file format <!lyr=; the geo:referenced output of &M& "mage! Thisgraphics file format can be used by all of &M&#s programs!

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Migration The width of the survey which must be added to allow migration of dipping eventsAperature toward the survey edges!

Prospect &eophysical Bone of interest; where survey model computations are addressed! Also referred to as the target! This generally refers to the top of the economicformation!

2eceiver .ine A line along which receivers are positioned at regular intervals! The distancebetween ad?acent receiver groups is the inline distance <9"= and the distancebetween ad?acent lines the crossline interval <9)"=!

2eceiver A pattern of live receivers for a given source point!Patch

Script File This file holds shooting information for a specific survey! The script defines whichreceivers are active for any given source point! Several recording systems canbe operated using script files!

Source .ine A line along which sources are positioned at regular locations! The distancebetween ad?acent sources is the inline spacing <S"= and the distance between

ad?acent lines the crossline spacing <S)"=!

(emplate The template defines the live set of receivers for any given source point!

'nit !in +ell This is the smallest group of bins for a survey design which is not redundant for aspecific midpoint diagnostic! The dimensions of the unit bin cell are dependenton the diagnostic

Documents

Mesa Training Manual