ProMAX 3D User Training Manual - pudn.comread.pudn.com/downloads272/sourcecode/math/1240848/promax3dhead.pdf · ProMAX 3D Seismic Processing and Analsysis: - pg 3. Overhead chap 1-

OverheadTitle - 1

ProMAX 3DUser Training Manual

copyright © 1999 by Landmark Graphics Corporation

626077 Rev. C JMarch 1999

OverheadAgenda - 1

Agenda

Monday

Introductions, Course Outline, and Miscellaneous Topics

• Differences between 2D and 3D• What makes 3D different from 2D in physical geometric

terms?• What is different in processing of 3D data relative to 2D?

System Overview

• Directory Structure• Program Execution• Ordered Parameter Files• Parameter Tables• Disk Datasets• Tape Datasets

ProMAX 3D Geometry

Discussion of 3D Tutorial Project

Initial Look at Trace Data

Build 3D Database from Observers Notes

• Input data into the spreadsheet• QC features within the spreadsheet/database• CDP Binning• Loading Geometry Directly to Field Data• Graphical Geometry QC

Geometry Core Path Overview

• Details of the Geometry Programs

ProMAX 3D Seismic Processing and Analsysis: - pg 1

OverheadAgenda - 2

Tuesday

Database From Geometry Extraction

• Extraction of first half• Extraction of second half• Full Extraction• Processing without a Database

Processing Sequence Flow

Preprocessing and Elevation Statics

• Top Mute and Decon Design Gate Picking• Decon Test and Interactive Spectral Analysis• Elevation Statics Computation• Pre-Processing Flow Execution

Superswath Definition

3D Stack and Volume Comparison

3D Stack Volume Displays

• Inline Displays• Cross Line Displays• Time Slice Displays• ProMAX 3D Viewer


OverheadAgenda - 3

Wednesday

3D Mix

• Apply a 3D Running Mix to the Initial Stack

3D Stack Comparisons

• Compare Inlines from Two Stack Volumes• Compare Crosslines from Two Stack Volumes• Compare Time Slices from Two Stack Volumes

ProMAX Marine 3D Geometry

Neural Net First Break Picking

Source Receiver Geometry Check

• Use First Breaks to check shot and receiver coordinates

3D Refraction Statics

• Compute Refraction Statics• Apply Refraction Statics

Statistical Trace Editing

• Compute statistics about each trace and Ensemble Statistics• Edit traces based on the statistics• Edit data using Statistics with DBTools and IDA


OverheadAgenda - 4

Thursday

3D Residual Statics

• F-XY Decon Model Building• Cross Correlation Gate Picking• Pick the Autostatics Correlation Gate• Cross Correlation Computation• External Model Autostatics Computation• Eigen Stack Model Building• Residual Static Application and Stack

Velocity Analysis and the Volume Viewer

• Supergather Generation and Offset Distribution QC• Precomputed Velocity Analysis

ProMAX Land Swath Geometry

• Simulated Multi-cable Swath shoot


OverheadAgenda - 5

Friday

3D Dip Moveout

• Offset Binning Parameter Determination• DMO to Gathers 3D• Parallel Processing Overview• DMO Stack 3D

CDP Taper on Stack Data

3D Velocity Viewer/Editor

• Edit and Smooth the RMS Velocity for FK Migration• Velocity Field Gridding and Smoothing• Convert to Interval Velocity

Migration

• Stolt 3D Migration• Phase Shift Migration• PSPC 3D Depth Migration• Explicit FD 3D Time Migration• Explicit FD 3D Depth Migration

Land Geometry Using SPS Survey Data


OverheadPreface - 1

Differences between 2D and 3D

Physical

What makes 3D different from 2D in physicalgeometric terms?

• 3D surface geometry - spatial distribution ofshots and receivers

• multiple cables / higher number of traces/shot

• variation in azimuth of CDP traces• Data volumes are generally much larger— tape to tape processing

— more computational power


OverheadPreface - 2

Differences between 2D and 3D

Processing

What is different in processing of 3D data relativeto 2D?

• 3D Subsurface Binning• 3D Geometry QC procedures• 3D Stack comparison techniques (header

tricks)— inline - crossline - time slice plots

• 3D Refraction Statics --- program• 3D Residual Statics— model building

— correlation gate picking

• 3D Velocity Analysis• 3D Velocity Viewer/Editor• 3D Dip Velocity Analysis• 3D DMO• 3D Migration


Overheadchap 1- 1

System Overview

In this chapter we discuss some of thebehind-the-scenes program operation, aswell as basic ProMAX framework.

Topics covered in this chapter:

❏ Directory Structure

❏ Program Execution

❏ Ordered Parameter Files

❏ Parameter Tables

❏ Disk Datasets

❏ Tape Datasets

ProMAX 3D Seismic Processing and Analsysis: 1-pg 1

Overheadchap 1- 2

ProMAX Directory Structure/sys

/port

/etc

/scratch

/queues

config_fileproductinstall.docpvmhostsqconfiglicense.dat

/data

/help

/menu

/misc

/plot

/lib

/bin

/exe

/promax3d

lib*.a

/promax

*.menuProcesses

/frame

/sdi

/3rd party

super_exec.exe

*.exe

exec.exe

*.lok - Frame help*.help -ASCII help

*_stat_math*.rgb-colormapsProMax_defaults

$PROMAX_HOME

/area /line(or $PROMAX_DATA_HOME)

(default=/advance)

/promax3d

/promax

/promaxvsp

/promaxvsp

promaxpromax3d

promaxvsp

software


Overheadchap 1- 3

ProMAX Data Directories

/Data

/AreaDescNameProject

/LineDescName17968042TVEL31790267TGAT36247238TMUT12345678CIND12345678CMAP

/12345678HDR1HDR2TRC1

/Flow1

TRC2

DescName

job.output

/OPF.SINOPF60_SIN.GEOMETRY.ELEV

/OPF.SRF

A Flow subdirectoryTypeName

packet.job

and its files

Parameter Table files

Index and Map Dataset files

Dataset subdirectoryand Header and TraceDataset files

PROMAX_DATA_HOME

or

#s0_OPF60_SRF.GEOMETRY.ELEV

/OPF.SIN Databasesubdirectory anda non-spanned file

/OPF.SRF Databasesubdirectory and aspan file

Area subdirectoryand its files


Overheadchap 1- 4

Program Execution

.


Overheadchap 1- 5

Processing Pipeline Diagram

AGC

F-K FilterTrace Display

SocketTool

Disk DataInput

Disk Data Output


Overheadchap 1- 6

Multiple Pipes in One Flow

AGC

F-K Filter

Decon

Disk DataInput

Disk Data

Disk Data Input, Tape DataInput and standalone toolsalways start new pipeswithin a single flow

One pipe must completesuccessfully before a newpipe will start processing

NMO

CDP Stack

Bandpass

Disk DataInput

Disk Data

Filter

Output

Output


Overheadchap 1- 7

ProMAX Process Types

Simple Tools

Accepts and returns a single seismic trace

Ensemble Tools

Accepts and returns a gather of seismictraces

Complex Tools

Accepts and returns a variable number ofseismic traces (eg. stack)

Panel Tools

Accepts and returns overlapping panels oftraces

Stand-Alone Processes

Processes that run independently

Socket Tools


Overheadchap 1- 8

Ordered Parameter Files (OPF)

Click to jump to the section

This section discusses the following issuesrelating to the Ordered Parameter Filesdatabase:

• Organization• Database Structure• File Naming Conventions

Organization

Reside in the Area/Line subdirectory.

The Ordered Parameter Files databasestores information in structured categories,known as Orders. (SHOT, RECEIVER, CDP.....)

In each Order, there are N slots available forstorage of information, where N is thenumber of elements in the order.

Each slot contains various attributes for oneparticular element of the Order.


Overheadchap 1- 9

Database File Orders

Table 1: Organization of Ordered Parameter Files

LIN (Line) Contains constant line information, such as final datum, typeof units, source type, total number of shots.

TRC (Trace) Contains information varying by trace, such as FB Picks, trimstatics, source-receiver offsets.

SRF(Surfacelocation)

Contains information varying by surface receiver location,such as surface locationx,y coordinates, surface locationelevations, surface location statics, number of traces receivedat each surface location, and receiver fold.

SIN(Source Index#)

Contains information varying by source point, such as sourcex,y coordinates, source elevations, source uphole times,nearest surface location to source, source statics.

CDP (CommonDepth Point)

Contains information varying by CDP location, such as CDPx,y coordinates, CDP elevation, CDP fold, nearest surfacelocation.

CHN (Channel) Contains information varying by channel number, such asChannel gain constants, channel statics

OFB(Offset Bin)

Contains information varying by offset bin number, such assurface consistent amplitude analysis. OFB is created whencertain processes are run, such as surface consistentamplitude analysis.

PAT (Pattern) Contains information describing the recording patterns.

Table 2: Additional Parameter Files for 3D

ILN (Inline) Contains information, constant within a 3D inline.(Numberof traces per line)

XLN(Crossline)

Contains information constant within a 3D crossline.(Number of traces per crossline)


Overheadchap 1- 10

OPF Matrices (spreadsheets)

SIN (Sources) Database

SRF (Receivers) Database


Overheadchap 1- 11

Database Structure

Each order is contained within a subdirectoryunder Area and Line.

For example, the Trace Ordered ParameterFiles are in the subdirectory OPF.TRC.

There are two types of files contained inthe OPF subdirectories:

— Parameter: Contain attribute values.

— Index: Holds the list of parameters and theirformats.

OPF files are of two types:

Span: The TRC, CDP, SIN, and SRF ordersmay generate span files if the database islarge.

Non-span: All other OPFs are non-span.

The geometry spreadsheet is a ProMAXdatabase editor. Modifying information withina spreadsheet editor and saving the changeswill automatically update the database.


Overheadchap 1- 12

Parameter Tables

OPF files are 1 number per “something”

1 X coordinate per shot

1 offset per trace

etc.

Parameter Tables are more than 1 numberper “something”

Mute Function

Multiple Offset/Time pairs pershot location

Velocity Function

Multiple VRMS/Time pairs perCDP location

Time Gate

Multiple Offset/Time pairs pershot location

Very Often, Parameter tables are referred toas part of the “Database”


Overheadchap 1- 13

Disk Datasets

A typical set of files might look like this:

/$PROMAX_HOME/data/area/line/12345678CIND/$PROMAX_HOME/data/area/line/12345678CMAP/$PROMAX_HOME/data/area/line/12345678/TRC1/$PROMAX_HOME/data/area/line/12345678/HDR1.

Table 1: Composition of a Seismic Dataset

File Name Contents

Trace(...TRCx)

File containing actual sample values for data trace.

Trace Header(....HDRx)

File containing trace header entries corresponding to datasamples for traces in the trace file. This file may vary inlength, growing as new header entries are added. Keeptrace headers in a separate file so trace headers can besorted without needing to skip past the seismic datasamples.

Map(....CMAP)

File keeps track of trace locations. Given a particular tracenumber, it will find the sequential trace number within thedataset. This rapidly accesses traces during processing. Themap file is a separate file, as it may grow during processing.

Index(....CIND)

File has free-form format information relating to the entiredataset, including sample interval, number of samples pertrace, processing history, and names of trace header entries.This file may grow during processing.


Overheadchap 1- 14

Disk Dataset Components

Relative Sizes

CIND

CMAP

HDRx

TRCx


Overheadchap 1- 15

Primary and Secondary Storage

Primary Storage

$PROMAX_HOME/etc/config_file

— primary disk storage partition:$PROMAX_HOME/promax/data 200

$PROMAX_DATA_HOME environmentvariable

Secondary Storage

$PROMAX_HOME/etc/config_file

— secondary disk storage partition:$PROMAX_HOME/data2 20 TRC OPF

— secondary disk storage partition:$PROMAX_HOME/data3 20 TRC

— secondary disk storage partition:$PROMAX_HOME/data4 20 OPF

— secondary disk storage partition:$PROMAX_HOME/data5 20


Overheadchap 1- 16

A typical set of disk data files

Map and Index in Primary Storage

— /$PROMAX_HOME/data/area/line/12345678CIND

— /$PROMAX_HOME/data/area/line/12345678CMAP

Trace and Headers in First SecondaryStorage

— /$PROMAX_HOME/data1/area/line/12345678/TRC1

— /$PROMAX_HOME/data1/area/line/12345678/HDR1

Trace and Headers in Second SecondaryStorage




Overheadchap 1- 17

Trace and Headers in Third SecondaryStorage




Overheadchap 1- 18

Tape Datasets

The tape devices used for the Tape DataInput, Tape Data Insert, and Tape DataOutput processes are declared in theProMAX device configuration window.

This allows access to tape drives anywhereon a network.

The machines that the tape drives areattached to do not need to be licensed forProMAX, but the fclient.exe program must beinstalled.

Tape Trace Datasets

Although the index and map files still resideon disk, copies of them are also placed ontape(s), so that the tape(s) can serve as aself-contained unit(s).


Overheadchap 2- 1

ProMAX 3D Geometry


• ProMAX Geometry Assignment Map

• Loading Geometry Directly to Field Data

• Description of Manhattan 3D Geometry

• Observers Report

• 3D Land Geometry Spreadsheet

• Final QC Plots From the Database

• Load the Geometry to the SEGY Data

• Graphical Geometry QC

• Geometry Core Path Overview

• Details of the Geometry Programs

• Pre-Geometry Database Initialization

• Inline Geometry Header Load after Pre-Initialization

ProMAX 3D Seismic Processing and Analysis: 2-pg 1

Overheadchap 2- 2

ProMAX Geometry Assignment Map

Disk Output - Global Options

Database

Ordered Para-Files

Extract

Spreadsheet

ASCIIO.B.Notes

Files

SEG-? Input

Inline Geom

Seismic Data

FieldData

Header Load

Import

(ProMAX)

DatabaseImport

GeometrySpreadsheet

Seismic Data

(ProMAX)

Disk DataOutput

Inline GeomHeader Load

UKOOA

UKOOAImport

Seismic Data

(ProMAX)

Valid TraceNumbersOverwriteTrace Headers

Disk DataOutput

meter-


Overheadchap 2- 3

Load Geom Directly to Field Data

Ordered ParameterFiles

Spreadsheet

ASCIIO.B.

SEG-? Input

Inline Geom

Seismic Data

FieldData

Header Load

(ProMAX)

Database

GeometrySpreadsheet

Seismic Data(ProMAX)

Disk DataOutput

UKOOA

UKOOAImport

Notes

Import

Import

Disk Output - From Survey Path

(by chan andheader word)


Overheadchap 2- 4

Description of Manhattan 3d Geom

Manhattan 3D - Shot and Receiver Basemap


Overheadchap 2- 5

Observer’s Report

• Group Interval --- 110 ft. Inline by 110 ft.cable spacing

Source Interval=N/A(random)

ReceiverInt.=110’CableInt.=110’

SampleInterval=4 ms

RecordLength=2.0 sec.

SourceStationNumbers

FieldFileID’s

No. of Chan/Shot

ReceiverStationatChan 1

ReceiverStationatLast Chan

1001 - 1016 1 - 16 240 1 240

1017 - 1024 17 - 24 240 73 312

1025 - 1031 25 - 31 240 145 384

1032 - 1043 32 - 43 240 217 456

1044 - 1053 44 - 53 240 289 528

1054 - 1061 54 -61 240 361 600

1062 - 1070 62 - 70 240 433 672

1071 - 1075 71 - 75 216 505 720

1076 76 120 505 624

1077 - 1081 77 - 81 216 505 720

1082 82 120 505 624

1083 - 1085 83 - 85 216 505 720


Overheadchap 2- 6

• Shot interval------N/A - Shots arepositioned randomly

• Azimuth ------------5.6 degrees East ofNorth

• CDP Spacing ------ 55 ft. inline by 55 ft.crossline


Overheadchap 2- 7

First Look at the Trace Data

1. Build the Flow “02 - Load Geom to headersand QC”:

Editing Flow: 02 - load geom to headers and qc

Add Delete Execute View Exit

SEGY Input

Type of storage ------------------------------ Disk Image

Enter DISK file path name ------------------------------

----------------/misc_files/3d/manhattan3d_segy_disk

MAXIMUM traces per ensemble ------------------- 240

Remap SEGY header values ------------------------ NOTrace Display

-------- Use All Default Parameters ---------------------


Overheadchap 2- 8

3D Land Geometry Spreadsheet

1. Add a line to your area called “databasefrom survey/obs logs”

2. Build the following flow:

3. Execute the flow.

4. Select File ➛ Setup from the main pulldown menu options.

Editing Flow: 02 - spreadsheet




Overheadchap 2- 9

Setup Window

110.0

110.0

0.0

0.0


Overheadchap 2- 10

Receivers Spreadsheet

Coordinate Import

1. Click on Receivers in the mainSpreadsheet window to bring up theReceivers spreadsheet.

2. Select File ➛ Import from the pull downmenus on the spreadsheet to read thecontents of an ASCII file into thespreadsheet.

When working with ASCII file import thereare three required steps:

• Identify the ASCII file• Define which numbers are in which

columns, and• Define which “cards” or rows to exclude

from the import.


Overheadchap 2- 11

Patterns Spreadsheet

Multiple patterns would be required if thegap changes in size or location, relative tothe channel numbers.

Multiple patterns would also be required inthe case where multiple cable lines areused and the receiver line numbers changefor different groups of shots.


Overheadchap 2- 12

Complete the Sources Spreadsheet

Fill out the FFID, Pattern, Pat Num Chn, andPat Shift columns.

• The FFID’s start at 1 and increment by 1for a total of 85 FFIDs.

• All of the shots use the same pattern whichdefines continuously numbered receivers;therefore, we can fill the Pattern columnwith 1’s.

• Pat Num Chn is the number of channelsper pattern. Use the observer’s log to getthe number of channels per shot.

• Pat Shift is the shift, in the receiver stationnumber of the first channel relative to thatentered in the PATTERNS Spreadsheet.Use the observer’s log to calculate thesevalues. These will not be the first receiverstation numbers, but will be the receivernumber -1.


Overheadchap 2- 13

Basemap & Prospect Level Azimuth

1. Open the receivers spreadsheet again.

2. QC the survey information by selectingView ➛ View All ➛ Basemap .

Using the Cross Domain Icon (“Double FoldIcon”) use the Mouse Button 3 option tomeasure the azimuth along a cable line.

Highlight Contributors tocross domain ICONAlso measures Distanceand Azimuth

ProMAX 3D Seismic Processing and Analysis,pages 16

Overheadchap 2- 14

A description of the interactivebinning Icons

• Zoom: This icon will put the display area in zoom mode.

• Rotate: This icon rotates the binning grid about a selectedpoint.

• Move: This icon translates or moves the grid.

• Size Grid Cells: This icon adjusts the grid cell dimensionsby either expanding or contracting the cells along one axisor the other.

• Add/Del Grid Cells: This icon adds or deletes rows orcolumns of cells from the grid.

• Spider: This icon displays selected bins in one of two spiderplot formats.


Overheadchap 2- 15

Interactive Spread QC using XYgraph

1. Open the receivers spreadsheet again.

2. Generate a Basemap by selecting View ➛View All ➛ Basemap .

Cross Domain Iconhighlights contributors


Overheadchap 2- 16

Defining the CDP binning grid

There are three ways to define the CDPbin grid parameters:

• Manually compute all of the requiredinformation

• Interactively define a proposed CDPbinning grid

or

• Automatically compute a CDP bin gridbased on an azimuth and bin sizes.

For this example we will look at the secondoption and interactively define a grid of CDPbins.


Overheadchap 2- 17

CDP Scattergram - Midpoint Plot:


Overheadchap 2- 18

Final QC Plots from the Database

DBTools; View ➛ Predefined ➛ CDP foldmap

• used to check CDP fold for variations

DBTools; View ➛ Predefined ➛ Receiver foldmap

• used to check for variations in receivermultiplicity

DBTools; View ➛ Predefined ➛ Source foldmap

• used to check for variations in number ofchannels per source

XDB; Wire/Field; SRF: X,Y, ELEV

• used to check receiver elevations

XDB; Wire/Field; SIN: X,Y, ELEV

• used to check shot elevations

DBTools; View ➛ Predefined ➛ SIN-SRF-Offset


Overheadchap 2- 19

• used to check the live receivers for eachshot

DBTools; View ➛ Predefined ➛ ILN-XLN-CDP

• used to map 3D CDP numbers to inlineand crossline coordinates

DBTools; View ➛ Predefined ➛ Offset-CDP-SIN

• used to check offset distribution in CDPsfor velocity analysis placement and DMObinning

2D plots of SIN vs. UPHOLE, DEPTH,NCHANS and SRF vs. FOLD

• used to check various attributes forsources and receivers

2D plots of ILN and XLN vs. FOLD

• used to find minimum and maximum liveinline and crossline numbers after binning


Overheadchap 2- 20

Load the Geometry to the SEGY Data

Recording channel number is assumedand there are not any “valid tracenumbers”, so we cannot match by “validtrace numbers”.

Editing Flow: 03 - load geom to headers and qc


SEGY Input





Remap SEGY header values ------------------------ NOInline Geom Header Load

Primary header to match database----------------FFID

Secondary header to match database ------------None

Match by valid trace number?------------------------No

Drop traces with NULL CDP headers?----------------No

Drop traces with NULL receiver headers?------------No

Verbose Diagnostics?-----------------------------------NoDisk Data Output

Output Dataset Filename----------------shots - raw data

New, or Existing, File?-------------------------------New

Record length to output--------------------------------0.

Trace sample format-------------------------------16 bit

Skip primary disk Storage?----------------------------No


Overheadchap 2- 21

Graphical Geometry QC

1. Modify the flow as follows:

Editing Flow: 02 - Load geom to headers and QC


>Disk Data Input<>Inline Geom Header Load<>Disk Data Output<Graphical Geometry QC*

Select input trace data file-------------”raw shot data”

Sin and SOU_SLOC range of dataset-----------------*:*

dB/sec gain value to apply-----------------------------6.

Specify LMO velocity functions(s)--------------1:0:9000

Additional bulk shift-------------------------------------25

Maximum time for each spliced trace---------------100

Maximum number of shots to splice-------------------10

Resulting max number of traces/ screen ----------- 340

Select display device-------------------------This Screen

Scalar for sample value multiplication ---------------1.

Trace scaling option ------------------------Entire Screen


Overheadchap 2- 22


How to Decide on the Primary GeometryPath

Vector Diagram

* Pre-Initialization

* Full Extraction

* From Field Notes and Survey

* Does Shot and Receiver X, Y, andstation information exist in theheaders and do you want to use it?

* Do you want to minimize thenumber of times that you have toread the data?

no

yesno

no

yes

OPTIONS QUESTIONS

* Do I have “Valid Trace Numbers”?yes

no


Overheadchap 2- 23


How to Decide on the Primary GeometryPath

Table Diagram

When the database is completed, theinformation contained in it is transferred totrace headers. The following question

Question Answer Option

Is shot and receiverstation, and x,yinformation in the headers;do you want to use it?

Yes

No

Full Extraction

Ask the next question

Do you want to minimizethe number of times toread the data?

Yes

No

From Field Notes andSurvey

Partial Extraction


Overheadchap 2- 24

determines how to match a trace in the datafile to a trace in the database:

Question Answer Option

Was a Full or PartialExtraction used to createthe database and a newoutput file written?

No

Yes

Inline Geom Header Loadby Chan and other traceheader words.

Inline Geom Header Loadby valid trace number


Overheadchap 2- 25

Details of the Geometry Programs

The specific processes that will be addressedare:

• Inline Geom Header Load• Extract Database Files• Geometry Header Preparation

Inline Geom Header Load is the mainprogram used to assign geometry values toindividual trace headers from the OPFdatabase files. One of then main issuesrelated to this geometry assignmentprocedure is to define how a trace in a datafile will be identified in the Trace OrderedParameter file. One of the options is to use aspecific trace header word called the "validtrace number".

Another program that may be used in thegeometry assignment procedure is calledExtract Database Files. We will see that thisprogram is one of the ways that the "validtrace number" can be generated by running itin either the Partial or Full extraction modes.


Overheadchap 2- 26

Geometry Header Preparation is anotherprogram that may be selected in thegeometry assignment procedures.


Overheadchap 2- 27

Steps Performed by Inline GeomHeader Load

• Inline Geom Header Load is the programthat populates the trace headers of aninput data file with the geometryinformation stored in the database.

• The outcome from running this programis to have a database and a data file that"match".

• This means that every trace in the outputdata file exists in the database and thereis a one to one correspondence in allvalues in the trace header to those in thedatabase.

• After a successful run each trace willalso be assigned the "valid tracenumber" if it was not pre-assigned usingExtract Database Files.


Overheadchap 2- 28

Trace Identification Options

There are two major options in this programpertaining to how to identify a trace in theinput data file with a trace in the database.These options are:

• to read the "valid trace number" from theinput trace header, or

• to read the recording channel number(automatic) and 1 or 2 trace headerwords that can uniquely identify thistrace as having originated from a uniqueshot (SIN) that exists in the shotdatabase.

Once a trace in a data file has beenidentified in the Trace OPF, theinformation in all of the OPF’s for thattrace is copied to the trace header.


Overheadchap 2- 29

Valid Trace Numbers

• Understanding this will help us decide onthe "best" course of action for our data.

• The "valid trace number" is simply aProMAX trace header word. Every tracein the database is numbered from 1 to N,where N is the total number of individualtraces in the database.

• This is a unique number for each trace inthe line or 3D project.

• A "valid trace number" combined withmatching geometry is a flag that willallow fast random access sorting of diskdatasets.

• Inline Geom Header Load matches thecurrent trace being processed to thedatabase and then copies all of the tracedependent values as well as the otherorder values to the trace header. Thelast thing that happens is that the tracesare "stamped" as matching thedatabase.


Overheadchap 2- 30

Valid Trace Number Origin

• The Extract Database Files programwrites this trace header word after itreads and counts a trace that it isentering into the TRC database. In thiscase the "valid trace number" is pre-assigned.

• If it is not pre-assigned, the Inline GeomHeader Load process will create it after itdetermines which trace in the databasecorresponds to a trace in a data file.

The "valid trace number" is a unique numberfor every trace and is stored in the traceheader as TRACE_NO.

This trace header word continues to existONLY if you write a new trace file after theextraction procedure.


Overheadchap 2- 31

Steps Performed By Extraction

Partial Extraction

Pre-Geometry Initialization (or partialextraction) which is sometimes used when noreceiver information exists in the incomingheaders.

Partial Extraction counts each of thefollowing:

• the number of traces encountered• the number of shots encountered• the number of traces per shotand then

• writes the trace count number and SIN tothe trace header


Overheadchap 2- 32

Steps Performed by Extraction

Extraction

Extraction is used when you want to extractthe shot and receiver location and coordinateinformation from the incoming headers.

Full Extraction counts each of the following:

• the number of traces encountered• the number of shots encountered• the number of traces per shot• the number of receivers encountered• the number of traces per receiverand then

• writes the trace count number and SIN tothe trace header

IF you have run the extraction in either mode,AND written a new trace data file, AND havenot altered the number of traces in thedatabase, you now have "valid tracenumbers" in the headers of the output dataset which you can use to map a trace in adata file to a trace in the database.


Overheadchap 2- 33

Between Extraction and Geom Load

After running Extract Database Files in eithermode there are many steps that need to becompleted prior to running the inline GeomHeader Load.

The extraction only partially populates thedatabase. More work will generally need tobe done in the Spreadsheets to input theremaining information.

After the Spreadsheets are complete, thenext step would be to complete the CDPbinning procedures and then finalize thedatabase.

With the database complete, you cancontinue with the next step of loading thegeometry information from the databases tothe trace headers. You may elect to addressa trace by it’s "valid trace number" assignedduring the extraction or you may read acombination of trace headers to identify thetrace.


Overheadchap 2- 34

Geometry Load Procedures

If extraction has been run, Inline GeomHeader Load operates as follows:

1. 1) it identifies the TRACE_NO of theincoming trace and finds that trace in theTRC database.

2. 2) It copies the appropriate TRC ordervalues to the trace header and then

3. 3) finds the shot, receiver, cdp, inline,crossline, and offset bin for that trace. Theappropriate values from those orders arethen copied to the trace headers as well.

If no extraction was run, Inline Geom HeaderLoad does not know exactly whichTRACE_NO it is looking for. It does knowwhich channel and shot to look for based onthe header word(s) that you selected. Giventhat this mapping is unique, the program nowknows which SIN and CHAN to look for in theTRC database. Once the entry is found, theTRACE_NO is copied to the headers and thesteps outlined in the first option areperformed.


Overheadchap 2- 35

Pre-Geometry Database Initialization

Note: In general, this process is notrecommended for medium to large volume3D projects.

To create a minimum set of entries in the SINand TRC Ordered Parameter files, basedupon the information found in the traceheaders of the data passed through the flow,selecting Yes to the option for Pre-GeometryExtraction.

Basically this process counts how manytraces, different FFIDs, and recordingchannels were present for each input FFID.

Therefore, it can build the TRC and SINordered database files.

An SRF OPF could be created, and may ormay not have any information in it.

Traces are assigned a “valid trace number”


Overheadchap 2- 36

Partial Extraction Flow Chart

This option may be appropriate for relativelysmall datasets which only have FFID andCHAN in the input trace headers. PreGeometry Initialization flow


Extract

Spreadsheet

ASCIIO.B.

SEG-? Input

Inline Geom

Seismic Data

FieldData

Header Load

(ProMAX)

Database

GeometrySpreadsheet


Disk DataOutput

UKOOA

UKOOAImport



Notes

Import

Import

DatabaseFiles

Marine DataSSD correction

Builds TRC and SINOPF’s onlyPre Geom Init = yes

Disk Output - Pre-Init Path


Overheadchap 2- 37

Partial Extract Flow

Make a new line called “from pre-initialization”.

Editing Flow: 01 - Pre-geom initialization


SEGY Input





Remap SEGY header values ------------------------ NOExtract Database Files

Is this a 3D survey------------------------------------- Yes

Data Type--------------------------------------------LAND

Source index method--------------------------------FFID

Receiver index method-----------------------STATIONS

Mode of operation --------------------------OVERWRITE

Pre-geometry extraction?-----------------------------YesDisk Data Output

Output Dataset Filename---------------”raw shot data”


Record length to output--------------------------------0.

Trace sample format-------------------------------16 bit



Overheadchap 2- 38

Inline Geom Header Load

after Pre-Initialization

Editing Flow: 03 - load geom to headers and QC


Disk Data Input

Read data from other lines/surveys ------------------No

Select Dataset---------------------------”raw shot data”

Trace read option---------------------------------Get All

Read the data multiple times?------------------------No

Process trace headers only?----------------------------Yes

Override input data’s sample interval ---------------NoInline Geom Header Load

Match by valid trace number?------------------------Yes



Verbose Diagnostics?------------------------------------NoDisk Data Output

Output Dataset Filename---------------”raw shot data”

New, or Existing, File?--------------------------Overwrite

Record length to output---------------------------------0.

Trace sample format--------------------------------16 bit



Overheadchap 3- 1

Database From Full Extraction


• Overview of Geometry Extraction

• Read and Extract the first SEGY file

• Complete the Database for the First Half

• Load the Geometry to the Trace Headers

• Read and Extract the Second SEGY file

• Complete the Database for the SecondHalf

• Load the Geometry to the Trace Headers

• Exercise Summary

• Full Extraction

• Processing without a Database


Overheadchap 3- 2

Geometry Extraction Chart


Extract

Spreadsheet

ASCIIO.B.

SEG-? Input

Inline Geom

Seismic Data

FieldData

Header Load

(ProMAX)

Database

GeometrySpreadsheet


Disk DataOutput

UKOOA

UKOOAImport



Notes

Import

Import

DatabaseFiles

Marine DataSSD correction

Builds TRC, SIN and SRFOPF’s onlyPre Geom Init = no

Disk Output - Extraction Path


Overheadchap 3- 3

Geometry Extraction

The following example assumes that traceheaders have everything required forgeometry assignment except inline, crosslineand binning information. This includes sourceand receiver x,y,z information, source andreceiver station locations, FFID and recordingchannel numbers, as well as uphole and shotdepth values.

This situation is commonly used whengeometry has been previously assigned tothe data using ProMAX, or if you receiveSEG-Y data with complete information in theheaders (or extended headers) from anothersource.


Overheadchap 3- 4

Overview of the Exercise

Read one SEGY file, extract the informationand build the database.

Run Geometry Spreadsheet and decide howwe want our lines and crosslines to benumbered:

• minimum crossline on the South

• minimum inline on the East.

Read the second file and append it’sinformation to the same database.

Run Geometry Spreadsheet again andexpand the grid to the West as the other halfof the data becomes available.

Complete the CDP Binning


Overheadchap 3- 5

Population After 1st Half Extraction

After loading the second half of the data, theentire subsurface grid will be populated.

inline 1xline 1

populated after thefirst extraction


Overheadchap 3- 6

Population after 2nd Half Extraction

inline 1xline 1

populated after thesecond extraction


Overheadchap 3- 7

Read and Extract the First SEGY File:

Remember to remap the SOU_SLOC andSRF_SLOC values from the extended SEGYheaders

Editing Flow: 01 - extract 1st half


SEGY Input

Type of storage to use: ----------------------------- Disk Image

Enter DISK file path name: -------------------------------------------------------/misc_files/3d/manhattan_first_half

MAX traces per ------------------------------------------------240

Remap SEGY header values ---------------------------------Yes

Input/override trace header entries ---------------------------------------------sou_sloc,,4I,,181/srf_sloc,,4I,,185/

Extract Database Files

Is this a 3D survey------------------------------------------------Yes

Data Type---------------------------------------------------------LAND

Source index method-------------------------------------------FFID

Receiver index method--------------------------------STATIONS

Mode of operation -----------------------------------OVERWRITE

Pre-geometry extraction?-----------------------------------------No

Extract CDP binning?----------------------------------------------No

Calculate trace midpoint coordinates?---------------------No

Extract OFB binning?----------------------------------------------NoDisk Data Output

Output Dataset FileName--------------shots-raw data (1st)


Overheadchap 3- 8

Geometry Setupt

Binning can be done by using existing valuesin the TRC ordered database file since theassociation of each trace with a shot andreceiver was extracted from the trace header.


Overheadchap 3- 9

QC the Input with a Basemap


Overheadchap 3- 10

Trace Assignment

In this case, the Assignment step isperforming the following calculations:

• Computes the Shot to Receiver Offset(Distance)

• Computes the Midpoint coordinatebetween the shot and receiver.

• Computes the Shot to Receiver Azimuth.


Overheadchap 3- 11

CDP Bin Origin and Direction

Flexibility in the binning parameters will allowyou to choose any corner of the project asthe origin of the Line, Xline and CDPnumbering.

You have complete flexibility in the inline andxline directions.

There are three rules by which you mustabide:

• 1) The Y axis is always parallel to thespecified azimuth

• 2) The X axis is always 90 degreesclockwise from the Y axis

and

• 3) The grid cell X and Y dimensionsmust be input as positive numbers.


Overheadchap 3- 12

Examples of Binning Parameters

Azimuth __________

Inline Parallel to ______

Y

X

45o

Inline 1Xline 1CDP 1

45o

Y

Azimuth __________

Inline Parallel to ______ 45o Inline 1

Xline 1CDP 1

225o

X

X

Y


Overheadchap 3- 13

Binning Parameters.Azimuth _______

Inline Parallel to ______5.6o

Inline 1Xline 1CDP 1

275.6o

X

XY

275.6

ProMAX 3D Seismic Processing and Analysis,pages 3-14 to15

Overheadchap 3- 14

CDP Scattergram / Midpoint Plot


Overheadchap 3- 15

Scattergram with Grid Overlay

this grid is 26 lines with 78 bins per line.

According to the supplier of the data we willeventually have 42 lines with 79 CDP’s perline.

gridorigin


Overheadchap 3- 16

Total Project Basemap

From this map it appears that the distanceY is greater than the distance X whichindicates that we need to add at least onedead crossline to our grid on the South.

X

Y


Overheadchap 3- 17

Fold QC after Binning

ZeroFoldCDPs

LiveCDPs


Overheadchap 3- 18

Load Geometry to the Trace Headers

Editing Flow: 03 - load geom to headers


Disk Data Input


Select Dataset-------------------”shots - raw data (1st)”

Trace read option----------------------------------Get All


Process trace headers only?---------------------------Yes


Match by valid trace number?-------------------------Yes


Drop traces with NULL receiver headers?-----------No


Output Dataset Filename--------------------------------

------------------------------------”shots - with geom(1st)”





Overheadchap 3- 19

Append the Second SEGY File

Editing Flow: 04 - extract 2nd half


SEGY Input


Enter DISK file path name -------------------------------

----------/misc_files/3d/manhattan_second_half

MAXIMUM traces per ensemble --------------------240

Remap SEGY header values ------------------------ Yes

Input/override trace header entries --------------------

---------------------sou_sloc,,4I,,181/srf_sloc,,4I,,185/Extract Database Files

Is this a 3D survey------------------------------------ Yes

Data Type--------------------------------------------LAND

Source index method--------------------------------FFID

Receiver index method-----------------------STATIONS

Mode of operation -------------------------------APPEND

Pre-geometry extraction?-----------------------------No

Extract CDP binning?----------------------------------No

Calculate trace midpoint coordinates?--------------No

Extract OFB binning?----------------------------------NoDisk Data Output

Output Dataset FileName--------------------------------

--------------------------------------shots- raw data (2nd)


Overheadchap 3- 20

Complete the Database for theSecond Half

Generate a Basemap using the View ➛ ViewAll ➛ Basemap


Overheadchap 3- 21

CDP Scattergram for all traces


Overheadchap 3- 22

Half Grid Overlay

Extend the grid to cover the entire survey


Overheadchap 3- 23

Complete CDP Binning using theBatch CDP Binning Tool

1. Build the following flow:

This process will perform the CDP binningand Finalization steps in a batch jobinstead of interactively using thespreadsheet.

Generate a QC plot from DBTools byselecting View ➛ Predefined➛ CDP foldmap

Editing Flow: 05 - CDP Binning


CDP Binning*

Binned Space Name ------------------------ “your grid”


Overheadchap 3- 24

DBTools Fold Map


Overheadchap 3- 25

Load Geometry to the Trace Headers

Editing Flow: 03 - load geom to headers


Disk Data Input


Select Dataset-------------------”shots - raw data 2nd)”



Process trace headers only?---------------------------No


Match by valid trace number?------------------------Yes




Output Dataset Filename---------------------------------

-----------------------------------”shots -with geom(2nd)”





Overheadchap 3- 26

Exercise Summary

• The first extraction was run in Overwritemode.

• The CDP grid was defined to cover theexisting project area.

• Since we ran the extraction and output adataset we could load the geometry byexisting “valid trace numbers.”

• The second extraction was run in Appendmode.

• We expanded the CDP grid after thesecond extraction making sure not to alterthe grid that was used for the first extractexcept to add bins for the new inlines.

• The second geometry assignment had noknowledge of the append and thereforereassigned all traces in the database.


Overheadchap 3- 27

Summary (Cont’d.)

• After running the second assignment stepwe have to completely rebuild the Tracedatabase. The dataset for the first half,however still matches the databasebecause we did not change the tracenumbers, SIN, SRF, CDP, ILN XLN, or OFBthat the traces from the first half contributeto. All we did was add new traces.

• After the second execution of the InlineGeom Header Load we now have twoseparate datasets, or Superswaths that wecan use to continue processing.


Overheadchap 3- 28

Full Extraction

Requires a fully populated trace headerincluding the following:

• Source X, Y coordinates and stationnumber,

• Receiver X, Y coordinates and stationnumber,

• CDP X, Y and CDP number,

• Iline and Xline numbers, and

• Offset bin number,

Builds all the database orders (not just TRC,SIN, SRF)

Edit LIN database in DBTools (View>LIN)

Useful for ProMAX datasets and SEG-?formatted data if the trace headers areremapped properly during input.


Overheadchap 3- 29

Example flow for First Extraction

Editing Flow: 01 - extraction


Disk Data Input

Read data from other lines/surveys ------------------Yes

Select Dataset-------------------”shots -with geom (1st)”



Process trace headers only?---------------------------No

Override input data’s sample interval ---------------NoExtract Database Files

Is this a 3D survey------------------------------------------------Yes

Data Type---------------------------------------------------------LAND

Source index method-------------------------------------------FFID

Receiver index method--------------------------------STATIONS

Mode of operation -----------------------------------OVERWRITE

Pre-geometry extraction?-----------------------------------------No

Extract CDP binning?---------------------------------------------Yes

Minimum cdp bin in survey --------------------------------------1

Calculate trace midpoint coordinates?---------------------No

Extract OFB binning?-------------------------------------No


Overheadchap 3- 30

Edit the LIN Database


Overheadchap 3- 31

Scroll to the bottom of the LIN Databaseeditor dialogue

Notice that with this technique, no gridinformation is present. You MUST fill in thegrid information manually.


Overheadchap 3- 32

Processing without a Database

Saves time and space

Must have fully-populated trace headers:

Interpolation routines resolve X, Ycoordinates in the following sequence:

• X, Y in trace headers

• LIN-ordered parameter file

• complete database

Must build LIN order to use CDP-orderedtables such as velocites tables

Does not allow surface-consistent processesor tools reading or writing the database (seemanual for complete listing)


Overheadchap 4- 1

Processing Sequence

Goals:

• Minimize the number of times you read thetraces

• Process the data in parts and thencombine

• Use reproduce traces and split to outputmultiple datasets with different processingin a single flow

• Save the data in the smallest format thatsubsequent processing will allow. Considerusing 8 bit trace sample format instead of16 or desampling your data for input toresidual statics or velocity analysis

ProMAX 3D Seismic Processing and Analysis: 4 - pg 1

Overheadchap 4- 2

full extraction load geometry

brute stack

refraction statics

residual statics

refr stat stack

resid stat stack

velocity analysis

dip moveout

final stack

migration

complete database

preprocessing

Geometry

Trace Processing

Imaging

ProMAX 3D Seismic Processing and Analysis: 4 - pg 2

Overheadchap 5- 1

Preprocessing and Elevation Statics

Both 2D and 3D land data need prestackprocessing and datum statics. This chapterpresents a brief review of typical prestackprocessing, including top mute, trueamplitude recovery, deconvolution filter andelevation statics.


❏ Top Mute and Decon Design Gate Picking

❏ Decon Test and Interactive SpectralAnalysis

❏ Apply Elevation Statics

❏ Super Swath Processing Strategies

❏ Preprocessing Flows


Overheadchap 5- 2

Top Mute and Decon Design Gate

In ProMAX 3D all parameter tables areinterpolated based on their X and Y locations.

In ProMAX 2D all interpolation is donelinearly by primary sort key.

• You may end up having to read manytapes to capture the shots of interest. Inthis flow we will output a dataset with justthe selected shots.

• This dataset will come in handy severaltimes during the course of theprocessing exercise.

• We will use the dataset to pick theparameter tables, train the neuralnetwork and as input to the ApplyElevation Statics and Apply RefractionStatics flows.

• Having a few shot records immediatelyavailable on disk may be a valuableresource.

1. Generate the following DBTools plot:

2D Matrix: X_COORD, Y_COORD,SOURCE, SOURCE


Overheadchap 5- 3

Shots for Parameter Table Picking

1001

10141071

1081

1067


Overheadchap 5- 4

Pick Parameter Tables Flow

Editing Flow: 06- Pick parameter tables


Disk Data Input

Select dataset--------------------------”shots-with geom (1st)”

Trace Read Option------------------------------------------------Sort

Interactive Data Access?-----------------------------------------No

Select primary trace header entry------------------SOURCE

Select secondary trace header entry ----------------- CHAN

Sort order for dataset---1001,1014,1067,1071,1081:*/Disk Data Insert

Select dataset-------------------------”shots-with geom (2nd)”




Sort order for dataset --1001,1014,1067,1071,1081:*/Disk Data Output

Output Dataset ---------------------------”shots - 5 test shots”Disk Data Input

Select dataset------------------------------”shots- 5 test shots”


Interactive Data Access?-----------------------------------------No


Select secondary trace header entry -------------- OFFSET

Sort order for dataset---1001,1014,1067,1071,1081:*/Automatic Gain ControlTrace Display

Number of ENSEMBLES /screen -------------------------------5

Trace Display MODE ----------------------------------Grayscale


Overheadchap 5- 5

Overheadchap 5- 6

Example Mute and Design Gate


Overheadchap 5- 7

Decon Test and Interactive SpectralAnalysis

1. Build a Flow to look at a power spectrumbefore and after decon:

Editing Flow: 7- decon test and ISA


Disk Data Input

Select dataset----------------------”shots - 5 test shots”

Trace Read Option------------------------------------Sort

Select primary trace header entry------------------SIN

Select secondary trace header entry ----------- CHAN

Sort order for dataset -------------------------------1:*/Automatic Gain ControlInteractive Spectral Analysis

Data select method ------------------------------ Simple

Display data by traces or ensembles---------Ensembles

----- All remaining parameters may default -----


Overheadchap 5- 8

Interactive Spectral Analysis

Simple Mode


Overheadchap 5- 9


Single Subset Mode

In this mode you can select a Single Subsetof the available data for the purposes ofcomputing the average power and phasespecta.


Overheadchap 5- 10


Multiple Subset Mode

2. Edit the parameters of the InteractiveSpectral Analysis to go from Single Subsetto Multiple Subset mode.

Also select to Freeze the selected subsets.


Overheadchap 5- 11

Multiple Subset Mode


Overheadchap 5- 12

Multiple Analysis Windows


Overheadchap 5- 13

Editing Flow: 7- decon test and ISA


Disk Data Input

Select dataset------------------------------”shots - 5 test shots”


Select primary trace header entry--------------------------SIN


Sort order for dataset -------------------------------------------1:*/Automatic Gain ControlReproduce Traces

Trace grouping to reproduce ---------------------- Ensembles

Total number of datasets -----------------------------------------2IF

Trace Selection MODE-------------------------------------Include

SELECT Primary trace header word -------------- REPEAT

SPECIFY trace list ----------------------------------------------------1ELSEIF

Trace Selection MODE-------------------------------------Include

SELECT Primary trace header word -------------- REPEAT

SPECIFY trace list ----------------------------------------------------2Trace Muting

Select mute parameter file ---------------”first break mute”Spiking/Predictive Decon

Use all defaults except...

Select decon gate parameter file --------------”decon gate”ENDIFInteractive Spectral Analysis

Data select method ---------------------------Multiple Subsets

Freeze the selected subset? ----------------------------------Yes

Display data by traces or ensembles --------- Ensembles

----- All remaining parameters may default -----


Overheadchap 5- 14

Elevation Statics

• Compute static time shifts to take theseismic data from their original recordedtimes, to a time reference as if the datawere recorded on a final datum (usuallyflat) using a replacement velocity(usually constant).

• Compute N_DATUM (or smooth surfaceused as the processing datum)

• Partition the total statics into two parts,the Pre (before) NMO term and Post(after) NMO terms relative to N_DATUM.

• Apply the Pre (before) -NMO portion ofthe statics and write the remainder to thetrace header.


Overheadchap 5- 15

Apply Elevation Statics vs. DatumStatics Calculation and Datum Statics

Apply

Apply Elevation Statics

• Calculate for entire database AND apply toinput dataset

• Cannot run two versions at the same timein one database

• Must calculate again to apply to anotherinput database

Datum Statics Calculation and Datum StaticsApply

• Calculate once

• Run multiple versions of apply at the sametime


Overheadchap 5- 16

Datum Statics Terminology

F_DATUM

N_DATUM

S_STATIC R_STATICC_STATIC

FNL_STAT

SurfaceElevation

S.P. CDP

Receiver

N_DATUM = floating datum

F_DATUM = final datum

S_STATIC = (F_DATUM - ELEV + DEPTH) / DATUMVEL

R_STATIC = [(F_DATUM - ELEV + DEPTH) / DATUMVEL] - UPHOLE

C_STATIC = 2 * [(N_DATUM - F_DATUM) / DATUMVEL]

N_DATUM = floating datum

NMO_STAT = S_STATIC + R_STATIC + C_STATIC

FNL_STAT = - C_STATIC

TOT_STAT = cumulative applied statics

NA_STAT = statics less than one sample period which are not-yet-applied

Trace Header Values:

Database Attributes:

(If TOT_STAT = 21.2 ms, and the sample period is 4 ms,

NA_STAT = 1.2 ms)

NMO_STAT

NMO_STAT


Overheadchap 5- 17

Comparison of Smoothed Surfacesbased on CDP Smoothing

Build and Execute a Flow to Compute the N-Datum:

Editing Flow: 07- N_DATUM test


Datum Statics Calculation

Elevation or Refraction----------------------------------Elevation

Final datum elevation-----------------------------------------1400

Replacement velocity -----------------------------------------9000

Database math method ------------------

--------------------------------------Shot Holes Using Uphole Info

NMO static method -------------------------------------Elevations

Length of smoother ------------------------------------------------51

Processing DATUM ---------------------------------NMO DATUM

Run ID-------------------------------------------------------------------01


Overheadchap 5- 18

True vs. Smoothed Elevation

3D Wireframe: CDP: X_COORD, Y_COORD, ELEV

3D Wireframe: CDP: X_COORD, Y_COORD, N_DATUM

51 point smoother


Overheadchap 5- 19

Smoothed Elevation with 15 pointsmoother.

3D Wireframe: CDP: X_COORD, Y_COORD, N_DATUM

15 point smoother


Overheadchap 5- 20

Superswath Definition

Swath 1

Swath 2

Swath 3

Swath 4

Swath 5Swath 6

ProMAXProcessFlow

Bundle the data sets intoeasy to managepartitions.

Process each partitionseparately up to Stackor DMO Stack

ProMAXProcessFlow


Overheadchap 5- 21

Preprocessing on the First Half

Editing Flow: 09-Preprocessing 1st half


Disk Data Input

Select dataset ---------------------- “shots - with geom (1st)”

Trace read option -------------------------------------------- Get AllDatum Statics Apply

Source datum statics ---------SIN GEOMETRY S_STAT02

Receiver datum statics------SRF GEOMETRY R_STAT02

CDP datum statics------------CDP CEOMETRY C_STAT02True Amplitude Recovery

Apply spherical divergence corrections ------------------Yes

Basis for spherical spreading ---------------------------1/dist

Apply inelastic attenuation corrections --------------------No

Get TAR velocity function from db? -------------------------No

Specify TAR velocity function ----------------------------

--------------0-9000,500-11200,1200-12500,2000-14000

Apply dB/sec corrections?-------------------------------------Yes

dB/sec correction constant ---------------------------------------6

Maximum application TIME --------------------------------2000Trace Muting

Select mute parameter file ---------------”first break mute”Spiking/Predictive Decon

Use all defaults except...

Select decon gate parameter file --------------”decon gate”Trace Display Label

Trace label -------------------------------decon and elev staticsDisk Data OutputOutput Dataset -------------------------”shots- preprocessed (1st)”


Overheadchap 5- 22

Preprocessing on the Second Half

Copy the flow that you just built to a new flow:

Change input and output

Editing Flow: 10-Preprocessing 2nd half


Disk Data Input

Select dataset --------------------- “shots - with geom (2nd)”

Trace read option -------------------------------------------- Get AllDatum Statics ApplyTrue Amplitude RecoveryTrace MuteSpiking/Predictive DeconTrace Display LabelDisk Data Output

Output Dataset ------------------”shots-preprocessed (2nd)”


Overheadchap 6- 1

3D Stack and Volume Comparison


❏ 3D RMS Velocity Field ASCII Import

❏ 3D Parameter Table Interpolation

❏ Picking a Post NMO Mute

❏ Stack 3D

❏ Merging the Partial Stacks

❏ CDP/Ensemble Stack

❏ 3D Stack Volume Displays

❏ ProMAX 3D Viewer

❏ 3D Mix

❏ 3D Volume Comparisons


Overheadchap 6- 2


Overheadchap 6- 3

3D RMS Velocity Field ASCII Import

From the list of flows level of the UserInterface select the Tables global optionand then select to go to the list of VEL(RMS (stacking) Velocity) tables.

2. Click Create. Donot click Add.


Overheadchap 6- 4

3D RMS Velocity Field ASCII Import

• Create New Table (NOT Add)

• Import ASCII velocity file

• Name Column Format

• Define Columns

• Apply Column Format

• Resolve the XY Coordinates

• QC your new Table using Edit


Overheadchap 6- 5

3D Parameter Table Interpolation

For ProMAX 3D all parameter tableinterpolation is performed in 3D using the Xand Y coordinates.

CDP Time Vel

CDP Time Vel X Y

2D Velocity Parameter Table

3D Velocity Parameter Table

1001 0 5000

1000 7000

2000 10000

1001 0 5000

1000 7000

2000 10000

10000 10000

Iline Xline

1 1


Overheadchap 6- 6

Overheadchap 6- 7

ProMAX 2D vs. 3D Parameter Tables

Velocity Table interpolation is a two stepoperation. A value at each of three velocitynodes is found at the desired time and thenthe velocity is interpolated using theDelauney Triangle approach.

3D Parameter Table InterpolationVelocity Functions in 3D

xy

t

a

b

cp

Known x,y, v, t point

Interpolated x,y, v, t point


Overheadchap 6- 8

Picking a Post NMO Mute

Editing Flow: 11 - Pick post NMO mute


Disk Data Input

Select dataset --------------shots - pre-processed (1st)

Trace read option ------------------------------------Sort

Interactive Data Access--------------------------------------No

Primary trace header entry -----------CDP bin number

Secondary trace header entry ------------------ NONE

Sort order for dataset ------------------------- 1615[7]/Disk Data Insert

Insertion mode---------------------------------------After

Select dataset -------------shots - pre-processed (2nd)

Trace read option ------------------------------------Sort

Primary trace header entry -----------CDP bin number

Secondary trace header entry ------------------- NONE

Sort order for dataset ------------------------- 1542[7]/In-line Sort

PRIMARY sort key ----------------------CDP bin number

SECONDARY sort key ---Signed source-receiver offset

Maximum traces per output ensemble---------------30Ensemble Stack/CombineNormal Moveout CorrectionBandpass FilterAutomatic Gain ControlTrace Display


Overheadchap 6- 9

Editing Flow: 11 - Pick post-NMO mute (cont)


Disk Data InputDisk Data InsertInline SortEnsemble Stack/Combine

Type of operation --------------------------------- Combine Only

Input ensembles per output ensemble -----------------------7

Maximum traces per output ensemble -------------------200

Warnings if max traces/ens exceeded?------------------Yes

Primary Trace Order Header Word -------------------- (CDP)

---------------------------------------------------------CDP bin number

Average the primary key values?-------------------------- Yes

Average the X and Y coord. of the primary key--------Yes

SECONDARY Trace Order Header Word--------(OFFSET)

-------------------------------------- Signed source-receiver offset

Output trace secondary key order -------------- AscendingNormal Moveout Correction

Direction for NMO application -------------------- FORWARD

Stretch mute percentage ----------------------------------------0.0

Apply any remaining static during NMO ---------------- Yes

Get 3D dip velocities? ---------------------------------------------No

Apply partial NMO?------------------------------------------------No

Get velocities from the database?---------------------------Yes

SELECT Velocity parameter file ----- imported from asciiBandpass Filter

All default values are acceptableAutomatic Gain Control

All default values are acceptableTrace Display

Primary trace LABELING ------------------------------------ CDP

Secondary trace LABELING --------------------------- OFFSET


Overheadchap 6- 10

Open a Mute Table and Name it.


Overheadchap 6- 11


Overheadchap 6- 12

Stack 3D

Sorting data for a large 3D volume can betime consuming and expensive. Thecapability exists in ProMAX 3D to generate“partial CDP stacks” from input files of anyprimary ensemble and merge these partialstacks together into one final CDP stack datavolume.

In the following exercises we will create twoseparate partial stacks and merge themtogether.

42 16

26 1

first halfinput data

secondhalfinput data


Overheadchap 6- 13


Overheadchap 6- 14

Editing Flow: 13- stack - initial (1st)


Disk Data Input

Select dataset ---------------------shots - pre processed (1st)

Trace read option -------------------------------------------- Get AllNormal Moveout Correction


Stretch mute percentage ----------------------------------------- 0.

Long offset correction----------------------------------------------No

Anisotropy correction parameter eta-----------------------0.0

Apply partial NMO?------------------------------------------------No

SELECT Velocity parameter file ----- Imported from asciiTrace Muting

SELECT mute parameter file ---- Post-NMO mute (brute)Stack 3D

Enter name of host -----------------------------

Number of worker threads----------------------------------------1

Restart with an existing stack? ------------------------------No

Minimum inline number -------------------------------------------1

Maximum inline number -----------------------------------------26

Minimum crossline number---------------------------------------1

Maximum crossline number ------------------------------------79

Exponent of normalization factor -------------------------- 0.5

Number of normalization scalars per trace ----------- 100

Apply final datum statics after stack? -------------------yes

Size of input trace memory buffer (MB)---------------------- 4

Size of stack trace memory buffer (MB) ----------------------4Trace Display Label

Trace label-------------------------------------------------Initial (1st)Disk Data Output

Output dataset filename--------------------stack-initial (1st)


Overheadchap 6- 15

Overheadchap 6- 16

CDP Contributors for the First File

This file contributes to CDP’s 4 - 2036 Thistranslates to Inlines 1 - 26.

42036


Overheadchap 6- 17

Run Stack3D on the OtherSuperswath:

The second file contributes to lines 16through 42.

Editing Flow: 14- stack - initial (2nd)


Disk Data Input

Select dataset --------------------shots - pre processed (2nd)

Trace read option -------------------------------------------- Get AllNormal Moveout CorrectionTrace MutingStack 3D

Minimum inline number -----------------------------------------16



Maximum crossline number ------------------------------------79Trace Display Label

Trace label -----------------------------------------------initial (2nd)Disk Data Output

Output Dataset Filename----------------stack - initial (2nd)


Overheadchap 6- 18

Merging the Partial Stacks:

Editing Flow: 15- merge 3d stacks


Disk Data Input

Select dataset -------------------------------- stack - initial (1st)

Trace read option -------------------------------------------- Get AllDisk Data Insert

Insertion Mode -------------------------------------------------- After

Select dataset ------------------------------- stack - initial (2nd)

Trace read option -------------------------------------------- Get AllStack Merge 3D






Maximum crossline number ------------------------------------79



Size of input trace memory buffer (MB)-----------------------4


Trace label ----------------------------------------- initial (merged)Disk Data Output

Output Dataset Filename-----------stack - initial (merged)


Overheadchap 6- 19

Alternative Stack Merge Flow

1. Look at this example flow for comparison:

You can use this approach if the partialstack jobs do not all finish at the sametime. You can start merging the completedfiles and continue merging as the filesbecome available. The file that is beingadded to within the Stack Merge must havebeen built originally to encompass all of thedata that is going to be added to it so itwon’t work for our case.

Editing Flow: 15- merge 3d append


Disk Data Input

Select dataset ------------------------------- Stack - initial (2nd)


Restart with an existing stack? -----------------------------Yes

Select existing stack filename -----------Stack -initial (1st)

Subtract input from stack? -------------------------------------No




Maximum crossline number ------------------------------------79Trace Display LabelDisk Data Output


Overheadchap 6- 20

Overheadchap 6- 21

The Subtraction Option

This option in the Stack Merge is intendedas a means by which you can remove theeffects of one (or more) bad trace(s) on anoutput stack volume. This is actually moreappropriate for stack merging DMO thanStack 3D outputs where a couple of badtraces affected many output traces.

If bad traces are detected, the inputprocess, Stack3D or DMO to Stack 3D canbe rerun with these traces only. Theresulting partial stack of this “bad” data canthen be subtracted from the total instead ofrerunning the entire stack and merge suitedeleting the offending input traces.


Overheadchap 6- 22


Inline Displays

Editing Flow: 16- Display Inlines


Disk Data Input

Select dataset -------------------------- stack - initial (merged)

Trace read option ------------------------------------------------ Sort

Interactive Data Access ---------------------------------------- Yes

primary trace header ------( ILINE_NO) 3D inline number

secondary trace header ---------(XLINE_NO) 3D crossline

tertiary trace header -----------------------------------------NONE

Sort order for dataset --------------------------1,5-40(5),42:*/Bandpass Filter

The default parameters will be adequateAutomatic Gain Control

The default parameters will be adequateTrace Display

Number of ENSEMBLES / screen ----------------------------10

Primary trace LABELING --------(ILINE_NO) 3D inline no.

Secondary trace LABELING ---(XLINE_NO) 3D crossline


Overheadchap 6- 23


Crossline Displays

Editing Flow: 17- Display cross lines


Disk Data Input

Select dataset ------------------------- Stack - initial (merged)



primary trace header -------( XLINE_NO) 3D crossline no

secondary trace header ----(ILINE_NO) 3D inline numbe


Sort order for dataset ----------------------1,10-70(10),79:*/Bandpass Filter




Primary trace LABELING -------(XLINE_NO) 3D crossline

Secondary trace LABELING -----(ILINE_NO) 3D inline no


Overheadchap 6- 24


Time Slice Display

Editing Flow: 18- Display time slices


Time Slice Input

Select dataset ---------------------------stack - initial (merged)

Type of time slice --------------------------------- Constant time

List of times ---------------------------------------- 200-1700(100)

Number of samples to stack -------------------------------------1

Store results in CDP database? ----------------------------- No

Horizontal axis ------------------------------ INLINE (ILINE_NO)

Horizontal axis increment --------------------- DECREASING

Vertical axis increment ------------------------- DECREASINGTrace Display Label

Trace label ----------------------------------------- initial (merged)Trace Display

number of ENSEMBLES/screen ----------------------------- 16

Trace gap between ensembles----------------------------------3

Trace display MODE----------------------------------- Grayscale

Primary trace LABELING ---------- slc_time (user defined)



Overheadchap 6- 25

Time Slice Display Orientation

To match the display and a map view ofthis project, set the Horizontal axis to beInlines Decreasing to the right and Verticalaxis to Decrease, thus plotting Xline 79 onthe top and inline 1 on the right.

142

1

79

Inline Number

CrosslineNumber

horizontal


Overheadchap 6- 26

ProMAX 3D Viewer

Build and execute this flow

There are no parameters that need to beset for this standalone process.

The program may promt you as to whichmonitor to display the viewer on and asecond prompt will want to know where todisplay the data selection dialog boxes.

Editing Flow: 19- 3D Viewer


ProMAX 3D Viewer*


Overheadchap 6- 27

ProMAX 3D viewer


Overheadchap 6- 28

ProMAX Seismic Animator


Overheadchap 6- 29

ProMAX 3D Viewer - Inline, Trace,Timeslice


Overheadchap 6- 30

Velocity Animator


Overheadchap 6- 31

ProMAX 3D Viewer - Inline, Trace, andTimeslice with Velocity overlay

Overheadchap 6- 32

Overheadchap 6- 33


Overheadchap 6- 34

3D Mix

Editing Flow: 20- 3D mix on initial stack


3D Mix

Select dataset ---------------------- stack - initial (merged)

IN-LINE the X-LINE sort order--------------------------- *:*/

Trace mixing algorithm --------------------- Weighted Mix

Exclude ‘hard’ zeros?------------------------------------- Yes

Trace weights for mixing ---------------------- 1.0,1.0,1.0

Number of traces to mix over------------------------------- 3

Type of trace edge taper ------------------ Fold edge back

Application mode for mixed traces--------------- Normal

Steer trace mix along a velocity dip?------------------ No

Number of applications ------------------------------------- 1

Re-apply mutes after mixing --------------------------- YesTrace Display Label

Trace label ------------------------------------ initial (3dmix)Disk Data Output

Output Dataset Filename---------stack - initial (3dmix)


Overheadchap 6- 35

Overheadchap 6- 36

3D Stack Volume Comparison

Compare Inlines

1. Input both datasets

2. Inline Sort by:

• ILINE

• DS_SEQNO

• XLINE

3. Display labeling by:

• Primary: ILINE

• Secondary: XLINE


Overheadchap 6- 37

Compare Inlines flow

Editing Flow: 21- Compare inlines


Disk Data Input



Interactive Data Access ------------------------------------------No


secondary trace header ----(XLINE_NO) 3D crossline no


Sort order for dataset --------------------------1,5-40(5),42:*/Disk Data Insert

Insertion mode -----------------------------------------------Merged

Maximum traces per output ensemble -----------------------0

Select dataset --------------------------- Stack - initial (3dmix)



secondary trace header ----(XLINE_NO) 3D crossline no


Sort order for dataset --------------------------1,5-40(5),42:*/

Force datasets to merge -----------------------------------------No

Observe dataset boundaries ---------------------------------Yes


Overheadchap 6- 38

Compare Inline flow (cont.)

Editing Flow: 21- Compare inlines


Disk Data InputDisk Data InsertInline Sort

PRIMARY sort key ---------- (ILINE_NO) 3D inline number

SECONDARY sort---------------(DS_SEQNO) Input datasetsequence number

TERTIARY sort key----(XLINE_NO) 3D crossline number

Maximum traces per output ensemble -------------------- 79

Number of traces in buffer ------------------------------------160

Buffer type ----------------------------------------------------Memory

Sort key which controls End-of-Ensemble-----Secondary

Bandpass Filter




Primary trace LABELING ---------(ILINE_NO) 3D inline no

Secondary trace LABELING ---(XLINE_NO) 3D crossline>Trace Display<

Number of ENSEMBLES / screen ------------------------------1


Overheadchap 6- 39

Compare Cross line flow

Editing Flow: 22- Compare Cross lines


Disk Data Input



primary trace header -------( XLINE_NO) 3D crossline no

secondary trace header ---(ILINE_NO) 3D inline number


Sort order for dataset ----------------------1,10-70(10),79:*/Disk Data Insert

Insertion mode -----------------------------------------------Merged

Maximum traces per output ensemble -----------------------0

Select dataset --------------------------- Stack - initial (3dmix)


primary trace header ------( XLINE_NO) 3D crossline no.

secondary trace header ---(ILINE_NO) 3D inline number


Sort order for dataset ----------------------1,10-70(10),79:*/

Force datasets to merge -----------------------------------------No

Observe dataset boundaries ---------------------------------YesInline SortBandpass FilterAutomatic Gain ControlTrace Display>Trace Display<


Overheadchap 6- 40

Compare Cross line flow (cont)

Editing Flow: 22- Compare Cross lines (cont)


Disk Data InputDisk Data InsertInline Sort

PRIMARY sort key ---- (XLINE_NO) 3D crossline number


TERTIARY sort key----------(ILINE_NO) 3D inline number


Number of traces in buffer --------------------------------------90


Sort key which controls End-of-Ensemble-----SecondaryBandpass Filter




Primary trace LABELING ------ (XLINE_NO) 3D crossline

Secondary trace LABELING ---------(ILINE_NO) 3D inline>Trace Display<

Number of ENSEMBLES / screen ------------------------------1


Overheadchap 6- 41

Compare Time Slices from Two StackVolumes

1. Edit the Display Time Slices flow.

The most effective way is to execute thesame flow twice with two different input filesand then size the windows as appropriate tocompare the two volumes.

Editing Flow: 18- Display Time Slices


Time Slice Input

Select dataset --------------------------------------------- select file

Type of time slice --------------------------------- Constant time

List of times ---------------------------------------- 200-1700(100)

Number of samples to stack -------------------------------------1

Store results in CDP database? ----------------------------- No

Horizontal axis ----------------------------- IN LINE (ILINE_NO)

Horizontal axis increment --------------------- DECREASING

Vertical axis increment ------------------------- DECREASINGTrace Display Label

Trace label ------------------------ volume identifier label textTrace Display

number of ENSEMBLES/screen ----------------------------- 16

Trace gap between ensembles----------------------------------3

Trace display MODE---------------------------------- Grayscale

Primary trace LABELING ------------------------------- slc_time



Overheadchap 7- 1

Neural Net First Break Picking

Overview

• Must have geometry and valid tracenumbers to enable NN Picker in TraceDisplay

• Pick example first breaks in Trace Display

• Pick a time gate containing the first breaksto constrain the NN Picker

• Train the NN and save a weight table

• Review the NN picks on a few shots.

• Retrain if necessary

• Run NN First Break Picker on all the shotsin batch mode.


Overheadchap 7- 2

Neural Network FB Training Flow

Editing Flow: 23- Neural Network Picking


Disk Data Input

Select dataset------------------------------”shots - 5 test shots”




Sort order for dataset --1001,1014,1067,1071,1081:*/True Amplitude Recovery

Apply spherical divergence corrections ------------------Yes

Basis for spherical spreading ---------------------------1/dist

Apply inelastic attenuation corrections --------------------No

Get TAR velocity function from db? -------------------------No

Specify TAR velocity function ----------------------------

--------------0-9000,500-11200,1200-12500,2000-14000

Apply dB/sec corrections?-------------------------------------Yes

dB/sec correction constant ---------------------------------------6

Maximum application TIME --------------------------------2000Automatic Gain Control

The default parameters should be adequateTrace Display

Number of ENSEMBLES/screen -------------------------------1

Trace Display MODE ---------------------------------------WT/VA


Overheadchap 7- 3

NN FB Picking - Time Gate

Make the top of the time gate parallel to thetrend of the first breaks.


Overheadchap 7- 4

Neural Network First Break Picking

2. Alter the existing flow as follows:

Make sure you reset the Trace read optionto GET ALL.

Editing Flow: 23- Neural Network Picking


>Disk Data Input<Disk Data Input

Select dataset------------------------”shots - with geom (1st)”

Trace Read Option--------------------------------------------Get AllDisk Data Insert

Select dataset-----------------------”shots - with geom (2nd)”

Trace Read Option-------------------------------------------Get ALlTrue Amplitude RecoveryAutomatic Gain Control

The default parameters should be adequate>Trace Display<NN First Break Picker

Select weight matrix parameter file ---------------------- wt1

Number of traces in median line fit--------------------------11

Maximum trace to trace static --------------------------------20.

Starting offset to determine fb pick slope ----------- 1400.

Select time gate parameter file --------------------- NN GATE

First break storage------------------- Header and Database

4 digit ID to store pick time in the TRC----------------- 0001


Overheadchap 7- 5

QC Plots of the FB Picks

In XDB Database Display, generate aPointcloud display:

3D: Pointcloud: TRC: SIN, OFFSET,PICK0001

Also generate an XYGraph display:

3D: XYgraph: TRC, OFFSET, PICK0001, SIN


Overheadchap 7- 6

Using the First Break Pick Macro forQC

2. Use the Picking ➛ Edit Header Values(first breaks)... FB_PICK (First Break picktime) Importing First Break Picks

Editing Flow: 23-Neural Network Picking


>Disk Data Input<>Disk Data Insert<>True Amplitude Recovery<>Automatic Gain Control<>Trace Display<>NN First Break Picking<First Break Pick Macro*

Select dataset ---------------------------- shots - with geom (1)


primary trace header entry -----------------------------------SIN

secondary trace header entry --------------------------- NONE

sort order for dataset --------------------------------------------- */

Database parameter ------------ TRC NN_PICK PICK0001

Bulk shift static --------------------------------------------------- 25.

Specify LMO velocity --------------------------------- 1001:9000

Specify END time ----------------------------------------------- 200.

Number of display panels ---------------------------------------- 5

Trace scaling option ----------------------------------- Individual

------- remaining parameters can default-------


Overheadchap 7- 7

Import FB Picks from ASCII File

A good set of first break picks is available, ifyour results from the neural network were notgood.


Overheadchap 7- 8

Save NNPKDANG attribute

Review the imported picks

3D: XYGraph: TRC, OFFSET,NNPKDANG, SIN


Overheadchap 8- 1


Used to check your geometry by using thefirst arrival times to predict where the shotsand receivers were positioned relative to thegeometry definition.

Writes attributes are written to the SIN andSRF databases. These values can bedisplayed from the database for analysis.


Overheadchap 8- 2


Flow

Editing Flow: 24 - Source Rec Geom Check


Source Receiver Geom Check*

Select First Break Times ----- TRC NN-PICK NNPKDANG

Compute V1 from first break times? -----------------------Yes

Minimum Offset for analysis ---------------------------------600

Maximum Offset for analysis-------------------------------3000

Maximum Location Error -------------------------------------220.


Overheadchap 8- 3

Offset Range from First Break PickPlot

1. From XDB generate a 3D: XYgraph: TRC :OFFSET, NNPKDANG, SIN and measurethe offset value for the consistent refractor.

Values of 600 to 3000 ft seem reasonable

600 ft

3000 ft


Overheadchap 8- 4

Offset Range from Trace Display

1. Re-run the flow that we used to pick theparameter tables.

In this flow we selected 5 shots anddisplayed them as a function of offset.From this display you can select an offsetrange over a consistent refractor using a“top mute”.


Overheadchap 8- 5


Overheadchap 8- 6

Offset Range from Trace Display

Overheadchap 8- 7

Database Values

This process writes several attributes to theSIN and SRF databases.

XPREDICT - predicted X coordinate

YPREDICT - predicted Y coordinate

DPREDICT - Distance for survey data

VPREDICT - Velocity estimate over offsetrange selected

APREDICT - azimuth from survey topredicted coordinate

TPREDICT - average delay time


Overheadchap 8- 8

Analyze the Results using SimplePlots

• From XDB Databse Display, generate asimple plot of SIN:XPREDICT andXCOORD.

• Repeat the plot for YPREDICT andYCOORD.

• Repeat the previous plots from the SRFdatabase.

• You may also look at a graph ofDPREDICT for the shots and receivers


Overheadchap 8- 9

Analyze the Results using 3D Plots

1. From the XDB, plot a 3D: XYGraph: SIN:XPREDICT: YPREDICT: DPREDICT.

This plot shows the predicted x,ycoordinates for each shot location. Theseare color coded by the distance that theywere moved, relative to the original x,y.

2. Using the Display ➛ Source ➛ ControlPoints ➛ Black pull down menu, overplotthe source control points.

3. Using the Views pull down menu and thedistance measure option from the Double-fold icon, you can identify which shots havebeen moved.

Make the DPREDICT plot dominant byusing the Views ➛ Transparent ➛ Sinbased Posting of DPREDICT pull downmenu, and then measure the distance fromthe Xpredict-Ypredict point to the originalshots using MB3 from the double fold icon.Find the shot that is the correct distancefrom the new location.


Overheadchap 9- 1

3D Refraction Statics

This section covers the steps for calculatingand applying 3D refraction statics. First breakpicks are required as input into this process.


❏ 3D Refraction Statics Overview

❏ Coordinate-based Refraction Statics

❏ Archive Original Elevation Statics

❏ CDP Mean Static after Refraction Statics

❏ Refraction Statics Apply and Stack

❏ Compare Stacks


Overheadchap 9- 2

3D Refraction Statics Overview

3D Refraction Statics Model

• assigns picks with offset ranges torefractors

• assigns initial estimates of refractorvelocities and intercept times

• computes shot and receiver Delay Times

3D Refraction Statics Inversion

• computes an interval vs. depth model ofthe refractor layers by inverting the firstarrival times

3D Refraction Statics Computation

• computes shot and receiver statics throughthe computed interval velocity vs. depthmodel


Overheadchap 9- 3

3D Refraction Statics Decomposition

3D Refraction Inversion MethodsMETHOD PROCESS ADVANTAGES DISADVANTAGE

S

Back Projection Single Step Fast

Good for estimatinglong wavelengthvariations in delaytimes

Good as input toother methods

Does not updatevelocities

Not good for shortwavelengthvariations in delaytimes

AlgebraicReconstructionTechnique

Iterative Can be used forlarge datasets: useslittle memory

Resolves short andlong wavelength indelay times well forclean data

Slow

Not as good asconjugate gradientfor noisy data

Conjugate Gradient Iterative Fast

Resolves short andlong wavelengthvariations in delaytimes well for cleanand non clean data

Memory intensive;restricted to smallerdatasets


Overheadchap 9- 4

Refraction Statics Flow

There are three options that can be used todraw a straight line through a set of selectedpicks. The least square option (L2) is a goodchoice. Select Options ➛ L2

Editing Flow: 23- refraction statics


3D Ref Statics Model*

Select First Break Times ---- TRC NN_PICK NNPKDANG

Number of layers -----------------------------------------------------1

QC delay times ------------------------------------------------------No>3D Ref Statics Inversion*<>3D Ref Statics Computation*<


Overheadchap 9- 5

Least Squares fit of all the points inthe selected offset range.

Notice the large asterisk appearing in theleft hand screen at the center of gravity ofall the previously selected shots.

MB1

MB2

L2

Click MB3 to Save


Overheadchap 9- 6

QC the Delay Times

This time there should be two first breakcurves for each shot.



3D Refraction Statics Model*


Number of layers -----------------------------------------------------1

QC delay times ----------------------------------------------------Yes

Select source delay ---------- SIN GEOMETRY DLY10000

Select receiver delay --------SRF GEOMETRY DLY10000>3D Refraction Statics Inversion*<>3D Refraction Statics Computation*<

original first breaktimes

first break times adjustedby the delay times


Overheadchap 9- 7

3D Refraction Statics Inversion

Parameterization



>3D Refraction Statics Model*<3D Refraction Statics Inversion*


Minimum pick weight -----------------------------------------------0

Layer number ----------------------------------------------------------1

Inversion method ------------------------- Conjugate Gradient

Get delay times from database------------------------------Yes

Select source delay ---------- SIN GEOMETRY DLY10000

Select receiver delay --------SRF GEOMETRY DLY10000

Get refractor velocity from database ----------------------Yes

Select refractor velocity ----- SIN GEOMETRY VEL10000

Get offset range from database ---------------------------- Yes

Select offset parameter file -------- Offset Range, Layer 1

Refractor cell width ------------------------------------------ 1000.

Refractor cell height ------------------------------------------1000.

Maximum # iterations --------------------------------------------75

Interactive mode? ------------------------------------------------- No

New database entry?---------------------------------------------No>3D Refraction Statics Computation*<


Overheadchap 9- 8

3D Refraction Statics Computation

Parameterization

These statics corrections are labeledS_RFSTAT and R_RFSTAT in the sourceand receiver ordered database files.



>3D Ref Statics Model*<>3D Ref Statics Inversion*<3D Ref Statics Computation*

Number of layers------------------------------------------------------1

Compute V0 from UPHOLE data-----------------------------Yes

Layer 1source delays ------- SIN GEOMETRY DLY10000

Layer 1receiver delays -----SRF GEOMETRY DLY10000

Refr 1 velocity at sources----SIN GEOMETRY VEL10000

Refr 1 velocity at rcvrs-------SRF GEOMETRY VEL10000

Final datum elevation----------------------------------------1400.

Replacement velocity -----------------------------------------9000.


Overheadchap 9- 9

Elev Stat vs. Refr Stat Plot

Simple plots of S_STATIC vs. S_RFSTAT andR_STATIC vs. R_RFSTAT are useful.


Overheadchap 9- 10

Coordinate-based Refraction Statics

Compared to 3D Refraction Statics Model,Inversion, and Compute approach--

Advantages:

• more robust for noisy first breaks,

• does not require first breaks for every shot,and it is

• disk-based instead of memory-based, so itworks better on large surveys.

Disadvantages:

• Disk-based so it’s slower

• No graphical displays>>

use other ProMAX tools


Overheadchap 9- 11

Refractor offset ranges

Four methods are supported:

• User type in-manually enter SIN andrefractor offset values.

• Mute file-input a Top Mute file picked inTrace Display.

• Offset file-use the same offset table thatwas picked in the Refraction Statics Modelflow (first exercise in the chapter).

• Compute offsets-allow the software tocompute offsets using a line segment fitalgorithm.

Use Offset file from Refraction StaticsModel for the exercise


Overheadchap 9- 12

Editing Flow: 25 - refraction statics


Refraction Statics Calculation*Select First Break Time--------TRC:NN_PICK NNPKDANGNumber of layers -----------------------------------------------------1Identification number -----------------------------------------------1Minimum fold ----------------------------------------------------------1Shooting Geometry------------------------------------------------ 3DV0 Options ------------------ Compute V0 from uphole timesINPUT REFRACTOR OFFSET? ------------------------------ Yes

Refractor Offset specification---------------- OFFSET fileSelect offset parameter file ---- Offset Range, Layer 1

COMPUTE REFRACTOR VELOCITIES?------------------ YesType of INITIAL velocity computation ------------- MEANSmooth INITIAL velocities before output? ----------- YesLength of INITIAL velocity smoother ------------------ 201Edit first break times?-----------------------------------------No

COMPUTE DELAY TIMES? ------------------------------------ YesTYPE of delay time ALGORITHM----------Gauss-SeidelNumber of iterations ---------------------------------------------5Type of GS computation statistics------------------ MEANIterate refractor velocity? -----------------------------------YesSmooth velocity between iterations? ------------------YesLength of Velocity smoother-------------------------------201

COMPUTE REFRACTOR DEPTH MODEL? ------------- Yes


Overheadchap 9- 13

Editing Flow: 25 - refraction statics (cont)


First Refractor Smoothing -------------------No SmoothingCOMPUTE SOURCE and RECEIVER STATICS? ------ Yes

Final datum Elevation ------------------------------------1400Replacement method ------------------------ User specifiedReplacement Velocity --------------------------------------9000

COMPUTE RESIDUAL STATICS------------------------------YesNumber of iterations---------------------------------------------3Length of surface elevation smoother-------------------15Length of low frequency filter-------------------------------15


Overheadchap 9- 14

Overheadchap 9- 15

Overheadchap 9- 16

Compute Refraction Velocities

Three database entries are created in theSIN OPF:

• SIN REFR_OFF OFFPSS11 ---Nearoffset of refractor.

• SIN REFR_OFF OFFPSE11 ---Far offsetof refractor.

• SIN VELOCITY V0INIT11 ----Weathering Velocity.

Three additional database entries arecreated:

• CDP VELOCITY VCINIT11 -- CDPvelocity for 1st refractor.

• SIN VELOCITY VSINIT11 ----Sourcevelocity for 1st refractor.

• TRC F_B_PICK FBPEDIT1 ----Editedfirst break pick file


Overheadchap 9- 17

After Compute Delay Times

Three database entries are created:

• SIN DELAYTIM SDELAY11----SourceDelay times

• SRF DELAYTIM RDELAY11--- Receiverdelay times

• CDP VELOCITY VCFIN011---- FinalCDP velocities.


Overheadchap 9- 18

Compute Refractor Depth Model

Six database entries are created:

• SIN REFDEPTH SDEP_011---SourceRefractor Depth

• SIN VELOCITY VSFIN011 -- FinalSource velocity for 1st refractor.

• SIN VELOCITY V0FIN011 ---FinalWeathering Velocity

• SRF REFDEPTH RDEP_011--ReceiverRefractor Depth.

• SRF VELOCITY VRFIN011- - FinalReceiver velocity for 1st refractor.

• SRF VELOCITY V0FIN011 ---FinalWeathering Velocity


Overheadchap 9- 19

Compute Source And ReceiverStatics

Two database entries are created:

• SRF GEOMETRY RSTAT00X ---Receiver statics

• SIN GEOMETRY SSTAT00X ----Sourcestatics


Overheadchap 9- 20

Compute Residual Statics

Two database entries are created:

• SIN GEOMETRY S_RESIDN ---Sourceresidual statics

• SRF GEOMETRYR_RESIDN---Receiverresidual statics


Overheadchap 9- 21

Calculate and Apply Datum Static

Datum Statics Calculation in Refractionmode:

• Computes CDP mean statics (C_STATIC)based on floating datum, the final datumand the replacement velocity

• Only run if floating datum, the final datumand the replacement velocity change

Datum Statics Apply

• Removes previous statics including handstatics and shot delay corrections

• Uses refraction staics and elevations fromdatabase to compute NMO_STAT andFNL_STAT

• Applies integer multiple of sample periodportion of NMO_STAT and saves theremainder to NA_STAT (static not applied)for application later.

• Run with Refraction Statics Stack flow tosave time


Overheadchap 9- 22

Refraction statics apply and stack

The basic steps can be summarized asfollows:

• Apply the datum statics and output shotdata with refraction statics applied.

• Apply Normal Moveout and the post-NMOmute.

• Reproduce traces and split the flow.

• Condition the first set of traces for ResidualStatics and output desampled, 8 bit shotdataset.

• Stack the second set of traces and outputrefraction statics stack.


Overheadchap 9- 23

Editing Flow: 26-Stack-refr stat (1st)


Disk Data InputDatum Statics ApplyTrace Display LabelDisk Data OutputNormal Moveout CorrectionTrace MutingReproduce TracesSPLITBandpass FilterAutomatic Gain ControlResample/DesampleDisk Data OutputEND_SPLITSPLITStack 3DTrace Display LabelDisk Data OutputEND_SPLIT


Overheadchap 9- 24

Subflow: Datum Statics Apply

Editing Flow: 26-Stack-refr stat (1st)


Disk Data Input

Select dataset ---------------------shots - pre processed (1st)

Trace read option -------------------------------------------- Get AllDatum Statics Apply

Src datum statics db parm----------SIN GEOM SSTAT001

Rec datum statics db parm--------SRF GEOM RSTAT001

CDP datum statics db parm-------CDP GEOM C_STAT02Trace Display Label

Trace label --------------------------------------- refr stat appliedDisk Data Output

Dataset File Name ---------------------- shots - refr stat (1st)


Overheadchap 9- 25

Subflow: Apply NMO, post-NMO TraceMute and Split the Flow

Editing Flow: 26-stack-refr stat (1st) cont


Normal Moveout Correction



Apply any remaining static during NMO?----------------Yes

SELECT Velocity parameter file ----- imported from asciiTrace Muting

SELECT mute parameter file ----- post nmo mute (brute)Reproduce Traces

Trace grouping to reproduce -----------------------Ensembles

Total number of datasets -----------------------------------------2SPLIT

Trace selection MODE ------------------------------------ Include

Primary trace header - REPEAT (REPEATED ensemble)

Secondary trace header ----------------------------------- NONE

SPECIFY trace list --------------------------------------------------1/Bandpass Filter


The default parameters will be adequateResample/Desample

Output sample rate -------------------------------------------------8.

All other input variables ------------------------------DEFAULTDisk Data Output

Output Dataset Filename---temp-input to correlation (1)

Trace sample format -------------------------------------------8 bitEND_SPLIT


Overheadchap 9- 26

Subflow: Refraction statics stack

Editing Flow: 26-Stack-refr stat (1st) (cont)


SPLIT


Primary trace header - REPEAT (REPEATED ensemble)


SPECIFY trace list --------------------------------------------------2/Stack 3D


Operating system of host----------------- (as per instructor)


Minimum in-line number ------------------------------------------1

Maximum in-line number ----------------------------------------26

Minimum x-line number--------------------------------------------1

Maximum x-line number -----------------------------------------79



Apply final datum statics after stack? -------------------Yes



Trace label --------------------------------------------- refr stat(1st)Disk Data Output

Output Dataset Filename--------------stack - refr stat (1st)END_SPLIT


Overheadchap 9- 27

Second Superswath

Editing Flow: 27-Stack-refr stat (2nd)


Disk Data Input

Select dataset --------------------shots - pre processed (2nd)Disk Data Output

Output Dataset Filename ----------- shots - refr stat (2nd)Datum Statics ApplyNormal Moveout CorrectionTrace MutingReproduce TracesSPLITBandpass FilterAutomatic Gain ControlResample/DesampleDisk Data Output

Output Dataset Filename --temp-input to correlation (2)END_SPLITSPLITStack 3D

Minimum in-line number ----------------------------------------16



Maximum x-line number -----------------------------------------79Trace Display Label

Trace label ------------------------------------------- refr stat (2nd)Disk Data Output

Output Dataset Filename ------------stack - refr stat (2nd)End Split


Overheadchap 9- 28

Merging the Partial Stacks

Editing Flow: 18- Merge 3d stacks


Disk Data Input

Select dataset ---------------------------- Stack - refr stat (1st)

Trace read option ------------------------------------------- Get AllDisk Data Insert


Select dataset --------------------------- Stack - refr stat (2nd)











Size of stack trace memory buffer (MB) --------------------- 4Trace Display Label

Trace label --------------------------------------refr stat (merged)Disk Data Output

Output Dataset Filename---------stack -refr stat (merged)


Overheadchap 10- 1

Statistical Trace Editing

Trace Statistics:

• computes up to eight differentrepresentative statistics for individualtraces and writes them to the TRCdatabase.

• useful in obtaining statistical properties ofseismic traces.

• can average the statistics of a selectedtrace order and estimate the quality ofsource gathers, receiver gathers, andCDPs.

• Use either first breaks or time gates

Ensemble Statistics calculates ensembleaveraged properties.

Edit traces using statistics


Overheadchap 10- 2

Trace Statistics

• TRC_AMPL: average trace energy

• FB__AMPL: average first break energy

• PRE_FB_A: average pre-first breakenergy

• PRE_FB_F: average pre-first breakfrequency

• T_SPIKES: Spikiness: the ratio ofmaximum magnitude sample to tracesignal amplitude

• FRQ_PEAK: dominant frequency basedon a count of zero crossings within asignal window

• FRQ_WIDE: frequency deviation basedon statistical scatter of frequencyestimates

• AMPDECAY: estimated trace energydecay rate in db


Overheadchap 10- 3

Trace Statistics Flow

Editing Flow: 29- Trace Statistics


Disk Data Input

Select dataset ----------------------------------- shots - first half


Select dataset --------------------------------shots - second half

Trace read option --------------------------------------------Get AllDatabase/Header Transfer

Direction of transfer ------ Load TO trace headers FROM

Number of parameters ---------------------------------------------1

First database parameter--- TRC NN_PICK NNPKDANG

First header entry --------(FB_PICK) First break pick timeTrace Statistics

Types of trace statistics to compute ----------- TRC_AMPL

-------------------FB_AMPL PRE_FB_A PRE_FB_F T_SPIKES

-----------------------------FRQ_PEAK FRQ_WIDE AMPDECAY

Use first breaks or time gate------------------ FIRST BREAK

Form of statistic output------ DATABASE and HEADERSDisk Data Output

Output Dataset Filename ---------------------------- shots - all


Overheadchap 10- 4

Analyze the Results

XDB Database Display

• Select Display ➛ Get and view theTRCSTATS information in the TRC OPF.

• Note ranges of vales for each statistic forwhich you might elect to kill the traces.


Overheadchap 10- 5

Ensemble Statistics.

Only one statistic can be averaged perprogram execution.

XDB Database Display

• Select Display ➛ Get, and view theensemble statistic information in the SIN,SRF, and CDP OPFs.

Editing Flow: 29 - Trace Statistics


>Disk Data Input<>Disk Data Insert<>Database/Header Transfer<>Trace Statistics<>Disk Data Output<Ensemble Statistics*Ensemble Statistics*Ensemble Statistics*Ensemble Statistics*


Overheadchap 10- 6

Editing Data with Statistics

Now that you have identified some noiseusing different statistical approaches, whatwould be a simple way to edit the data?

1. Exit the flow and select Database from theglobal parameter menu. Using DBTools goto the TRC order and double click on someof the statistical attributes.

Note ranges of vales for each statistic forwhich you might elect to kill the traces.

2. Build a flow which will use trace statisticalentries to kill the bad traces as outlined onthe next page.

3. In Database/Header Transfer, select tomove data attributes from the TRC OPF tothe trace headers.

For the trace header entry, select “userdefined” and use the same name as thedatabase attribute.

You can transfer more than one set ofvalues in the same step.

4. Select Trace Kill/Reverse parameters to killthe noisy data.


Overheadchap 10- 7

For example, if you use FRQ_PEAK, selectFRQ_PEAK as the primary trace headerand in the trace list include 65-80. Selectone primary trace header for each TraceKill/Reverse.


Overheadchap 10- 8

Editing Flow: 30 trace kills by statistics


Disk Data Input

Select dataset --------------------------------------------- shots -all

Trace read option -------------------------------------------- Get AllReproduce Traces

Trace groupings to reproduce -------------------- Ensembles

Total number of datasets -----------------------------------------2IF


Primary trace header--------- REPEATED ensemble copy

Secondary trace header-------------------------------------NONE

SPECIFY trace list ----------------------------------------------------1Trace Kill/ReverseTrace Kill/ReverseTrace Display LabelELSEIFTrace Display LabelENDIFTrace Display


Overheadchap 10- 9

Editing Flow: 30 trace kills by statistics -cont


Disk Data InputDisk Data InsertReproduce TracesIFTrace Kill/Reverse

Trace editing MODE --------------------------------------------- Kill

Get edits from DATABASE ------------------------------------- No

PRIMARY edit list header word --------------------- t_spikes

SECONDARY edit list header word ------------------- NONE

SPECIFY traces to be edited --------------------------100-300Trace Kill/Reverse

Trace editing MODE --------------------------------------------- Kill

Get edits from DATABASE ------------------------------------- No

PRIMARY edit list header word --------------------- trc_ampl


SPECIFY traces to edit ---------200000000-1500000000Trace Display LabelELSEIFTrace Display LabelENDIF

Trace Display


Overheadchap 10- 10

Editing Flow: 30 trace kills by statistics -cont


Disk Data InputDisk Data InsertReproduce TracesIFTrace Kill/ReverseTrace Kill/ReverseTrace Display Label

Trace label ------------------------------------------------ with editsELSEIF


Primary trace header--------- REPEATED ensemble copy

Secondary trace header-------------------------------------NONE

SPECIFY trace list ----------------------------------------------------2Trace Display Label

Trace label ------------------------------------------------------- inputENDIFTrace Display

Header Plot Parameter -------------(TRC_TYPE) Trace type

Number of display panels ----------------------------------------2


Overheadchap 10- 11

Comparison Display

Check that the noisy data has been editedand you have not edited too many nearoffset traces.

The header plot of TRC_TYPE is a quickvisual aid to tell you which traces have beenedited.


Overheadchap 10- 12

Editing Data using Statistics withDBTools and IDA

This will be a somewhat complex workflowdemonstrating the power of DBTools andIDA. You will eventually have at least twodisplays from DBTools:

1) a 3D crossplot of TRC: TRC_AMPL,PRE_FB_A, TSPIKES color coded byAMPDECAY with histogram of FRQ_PEAK

2) a shot location map

working in conjuction with a Trace Display ofshot gathers.

The workflow will involve identifyinganomalous traces in the DBTools display andthen telling Trace Display to only show theshots that contain these anomalous traces.


Overheadchap 10- 13

Build the following flow

Start DBTools and generate two displays

Exit from the flow and start DBTools byclicking on the Database option from theglobal menu. bar.

Generate a shot location map using the View➛Predefined ➛Source Fold Map option.

Change to a monochrome color scheme andselect a color from the color palette.

Editing Flow: 31 trace kills using DBTools


Disk Data Input

Select dataset -------------------------------------------- shots - all


Interactive Data Access? -------------------------------------- Yes

Primary trace header entry -------- Source Index Number

secondary header entry ------------------------------------- None

Sort order list -------------------------------------------------------- */

Presort in memory or disk ------------------------------ MemoryTrace Display

Trace scaling option ------------------------------ Entire Screen


Overheadchap 10- 14

TRC_AMPL, PRE_FB_A, TSPIKES,AMPDECAY and FRQWIDE and the axes,color code and histogram respectively


Overheadchap 10- 15

View of 3D Crossplot from TRC OPF


Overheadchap 10- 16

Re-orient the display. Rotate until T_SPIKESaxis is coming out of the screen


Overheadchap 10- 17

Use the polygon select to encompass theanomalously high amplitude traces.


Overheadchap 11- 1

3D Residual Statics

Use two external model correlationautostatics processes: Cross CorrelationSum and Gauss-Seidel. Both of theseprocesses compute surface consistent staticsbased on trace correlations with externallybuilt stack model traces.

• Build a model using F-XY Decon

• Pick a cross correlation gate

• Compute external model correlations

• Compute External Model Autostatics

• Apply Residual Statics and Compare

• Build Eigen Stack Model

Must have geometry and a completedatabase

Already made the dataset for input to residualstatics in refraction statics flow.


Overheadchap 11- 2

Resource Management

Save space by using 8 bit format for:

• model traces,

• cross correlations,

• input to cross correlation sum autostaticsand

• velocity analysis.

Process dataset in parts and merge results ofexternal model correlations


Overheadchap 11- 3

F-XY Decon Model Building

Editing Flow: 32- External Mod - FXY decon


Disk Data Input

Select dataset -----------------------stack - refr stat (merged)

Trace read option --------------------------------------------- SORT

primary trace header------------------- (ILINE_NO) 3D inline

secondary trace header-------------- (XLINE_NO) 3D cross

Sort order for dataset -------------------------------------------*:*/F-XY DECON

The default parameters will be adequateBandpass Filter




All other input variables ------------------------------DEFAULTTrace Display Label

Trace label ------------------------------------------------FXY deconDisk Data Output

Output Dataset Filename-------external model - FXY dec

Trace sample format -------------------------------------------8 bit


Overheadchap 11- 4

Cross Correlation Gate Picking

Randomly picked Autostatics Horizon points

Inline number

Xlin

e nu

mbe

r


Overheadchap 11- 5

Correlation Area From RandomPoints

Area that would be Correlated

Inline number

Xlin

e nu

mbe

r


Overheadchap 11- 6

Minimum Picking Requirements

Inline number

Xlin

e nu

mbe

r

Absolute minimum requirements


Overheadchap 11- 7

3D View of Picking Requirements

Inline number

Xlin

e nu

mbe

r

x

x

x x


Overheadchap 11- 8

Pick the Autostatics Correlation Gate

Editing Flow: 33- Pick correlation gate


Disk Data Input

Select dataset -----------------------stack - refr stat (merged)

Trace read option --------------------------------------------- SORT

primary trace header-------(ILINE_NO) 3D inline number

secondary trace header-----(XLINE_NO) 3D crossline nu

Sort order for dataset ----------------------1,10-30(10),42:*/Bandpass Filter




Primary trace LABELING ---------------------------------- NONE

Secondary trace LABELING ----------(ILINE_NO) 3d inline

MODE of Secondary trace annotation ------------ Different


Overheadchap 11- 9

Statics Gate Naming Conventions

You will select a gate width (300 ms issuggested) and a smash (11 is the defaultand is irrelevant since we are using anexternal model).

You might want to think about a namingconvention for these tables since you mayelect to test a few different ones. Oneconvention you might use is a gate numberfollowed by a description:”

“01 - 300 wide centered at 650”

You can then name the statics output to thedatabase as:

SGEMFX01

For Statics - Gauss Seidel - FXY DeconModel - Gate 01


Overheadchap 11- 10

Cross Correlation Computation

Editing Flow: 34- External Mod corr (1st)


Disk Data Input

Select dataset ------------------temp- input to correlation (1)

Trace read option --------------------------------------------Get AllExternal Model Correlation

Select model trace dataset ---------- external model - FXY

Use autostatics horizon or gate file? ------------ HORIZON

Select autostatics horizon file ---- 01- 300 wd - 650 (ish)

Minimum live samples in a gate (percent) --------------- 50

Maximum static shift --------------------------------------------- 36

Write corr pick TIMES to database ------------------------ Yes

Write corr pick AMPLITUDES to database -------------- Yes

Write quality control estimates to database ----------- Yes

Database mode --------------------------------------------------New

Enter 4 digit ID number ------------------------------------- FX11Disk Data Output

Output Dataset Filename----------xcorrs FXY - gate 01 (1)



Overheadchap 11- 11

QC the Picks from the First Half

Make a simple plot using XDB of theTRMFX11 attribute from the TRC database.

Notice that only the picks for the first halfhave live values.


Overheadchap 11- 12

Correlate the Second Half

Editing Flow: 35- External Mod corr (2nd)


Disk Data Input

Select dataset ------------------temp- input to correlation (2)

Trace read option --------------------------------------------Get AllExternal Model Correlation

Enter 4 digit ID number ------------------------------------- FX12Disk Data Output

Output Dataset Filename----------xcorrs FXY - gate 01 (2)



Overheadchap 11- 13

QC the Picks from the Second Half

Make a simple plot using XDB of theTRMFX12 attribute from the TRC database.

Notice that only the picks for the first halfhave live values.


Overheadchap 11- 14

Merge the Two Halves:

Editing Flow: 37- merge pick attributes


Database Parameter Merge*

Enter number of parameters to merge -----------------------2

DB INFOTYPE PARM 1 --------- TRC STATICS TRM_FX11

Start location of PARM 1 ------------------------------------------ 1

End location of PARM 1 ----------------------------------- 19848

DB INFOTYPE PARM 2 --------- TRC STATICS TRM_FX12

Start location of PARM 2 ------------------------------------------ 1

End location of PARM 2 ------------------------------------19848

Select type of merge ------------------------------------------ Mean

Merged parameter information type ----------------- statics

Merged parameter name -------------------------- TRMFXY01Database Parameter Merge*

Enter number of parameters to merge -----------------------2

DB INFOTYPE PARM 1 --------- TRC STATICS QLT_FX11

DB INFOTYPE PARM 2 --------- TRC STATICS QLT_FX12

Merged parameter name --------------------------- QLTFXY01


Overheadchap 11- 15

QC the merged values

You should see a continuous plot withvalues for all traces.

Merged Picks in DBTools(notice histogram of statics values)


Overheadchap 11- 16

External Model Autostatics Computation:

Editing Flow: 37-Compute residual statics


EMC Autostat: Gauss-Seidel*

TRC database correlation ---- TRC STATICS TRMFXY01

Statics partitioning iterations -------------------------------- 3

Maximum source or receiver static ----------------------- 30

Min trace offset MAGNITUDE -------------------------------- 0

Max trace offset MAGNITUDE ---------------------- 999999

Weight solutions by pick quality factors --------------- Yes

Alpha trimmed mean percentage-------------------------- 40

Length of CDP structure smoothing ------------------------ 3

Dampen the structure term at low fold? --------------- Yes

Create a NEW database entry for each run? --------- Yes

Enter 4 digit ID number ----------------------------------- FX01


Overheadchap 11- 17

Expand the Flow

Run the Xcor Sum Decomposition.

Editing Flow: 37-Compute residual statics


>EMC Autostat: Gauss-Seidel*<Disk Data Input

Select dataset ------------------------ xcorrs FXY - gate 01 (1)

Trace read option --------------------------------------------Get AllDisk Data Insert

Select dataset -------------------------xcorrs FXY - gate 01 (2)

Trace read option --------------------------------------------Get AllDisk Data Output

Output Dataset Filename------- xcorrs FXY - gate 01 (all)

Trace sample format -------------------------------------------8 bitEMC Autostat: XCor Sum*

Input correlations from Tape or Disk? ------------------ Disk

Select Dataset -----------------------xcorrs FXY - gate 01 (all)

First statics computation domain ------------------------- CDP

Second statics computation domain ----------------- Source

Third statics computation domain ----------------- Receiver

Fourth statics computation domain ------------------- NONE

Adjust corr by a previous SOURCE static ---------------- No

Adjust corr by a pervious RECEIVER static ------------- No

Adjust corr by a previous CDP RESID --------------------- No

Method for correlation summing ------ Min/Max Exclude

Maximum source or receiver static ------------------------- 30

Create a NEW database entry ------------------------------ Yes

Enter 4 digit ID number ------------------------------------- FX01


Overheadchap 11- 18

View the Results Using XDB

• View the SRF and SIN database entriescreated by Gauss-Seidel calledSGEMFX01.

• View the SRF and SIN database entriescreated by Xcor-Sum called SPEMFX01.

You can do both simple graphs and/or youmay elect to generate some color contourplots using the Field option in the 3D displayfunctions.


Overheadchap 11- 19

Residual Statics Application Flow

Editing Flow: 38- resid stat stack (1st)


Disk Data InputApply Residual Statics

Reproduce Traces

SPLITNormal Moveout CorrectionTrace MutingStack 3DTrace Display LabelDisk Data OutputEND_SPLIT

SPLITBandpass FilterAutomatic Gain ControlResample / DesampleDisk Data OutputEND_SPLIT


Overheadchap 11- 20

Flow Breakdown

The basic steps can be divided as follows

• Apply the residual statics

• Apply Normal Moveout and the postNMO mute and produce a stack of thedata with the residual statics applied.

• Select only the lines for velocity analysis

• Apply pre-velocity analysis processingand output a temporary dataset builtspecifically for velocity analysis.Read thefirst half shot file with preprocessingapplied.


Overheadchap 11- 21

Apply the Residual Statics

and Reproduce the Traces

Editing Flow: 38- resid stat stack (1st) cont


Disk Data Input

Select dataset ------------------------------shots - refr stat(1st)

Trace read option -------------------------------------------- Get AllApply Residual Statics

Normal database entry naming mode?------------------- No

Source residual static ---------- SIN STATICS SGEMFX01

Receiver residual static ------- SRF STATICS SGEMFX01Reproduce Traces

Trace grouping to reproduce --------------------- -Ensembles

Total number of datsets -------------------------------------------2


Overheadchap 11- 22

Stack the First Half of the Data

Editing Flow: 38 - resid stat stack (1st) (cont)


SPLIT


Primary trace header ------REPEAT (Repeated ensemble


SPECIFY trace list --------------------------------------------------1/Normal Moveout Correction




SELECT Velocity parameter file ----- imported from asciiTrace Muting

SELECT mute parameter file ----- post nmo mute (brute)Stack 3D





Trace label -------------------------------------------resid stat(1st)Disk Data Output

Output Dataset Filename-------------stack -resid stat (1st)END_SPLIT


Overheadchap 11- 23

Velocity Analysis Locations

Proposed CDP Center Positions For Analysis

5 15 25 35

20

40

60

1 421

79

Inline Number

XlineNumber


Overheadchap 11- 24

Write Data For Vel Analysis

Editing Flow: 38- resid stat stack (1st) cont


SPLIT


Primary trace header--- REPEAT (REPEATED ensemble

Secondary trace header ----ILINE_NO (3d inline number

SPECIFY trace list ---------------2:3-7,13-17,23-27,33-37/Bandpass Filter




All other input variables ------------------------------DEFAULTDisk Data Output

Output Dataset Filename------temp - input to velanal (1)

Trace sample format -------------------------------------------8 bitEND_SPLIT


Overheadchap 11- 25

Run the Other Superswath.

Editing Flow: 39- resid stat stack (2nd)


Disk Data Input

Select dataset ----------------------------shots - refr stat (2nd)

Trace read option -------------------------------------------- Get AllApply Residual StaticsReproduce TracesSPLITNormal Moveout CorrectionTrace MutingStack 3D

Minimum in-line number ----------------------------------------16




Trace label ----------------------------------------- resid stat (2nd)Disk Data Output

Output Dataset Filename ----------stack - resid stat (2nd)END_SPLITSPLITBandpass FilterAutomatic Gain ControlResample / DesampleDisk Data Output

Output Dataset Filename ------temp - input to velanal(2)END_SPLIT


Overheadchap 11- 26

Merging the Partial Stacks

Editing Flow: 40- Merge 3d stacks


Disk Data Input

Select dataset -------------------------- Stack - resid stat (1st)



Select dataset ------------------------- Stack - resid stat (2nd)


Enter name of host ----------------------------------------------------











Trace label ------------------------------------resid stat (merged)Disk Data Output

Output Dataset Filename------stack -resid stat (merged)


Overheadchap 11- 27

Eigen Stack Model Building

Eigen Stack process uses the Eigen vectordecomposition techniques to isolate theprimary component stack from a supergatherof prestack traces.

.

Cartoon of Eigen Stack Decomposition

Input Traces on CDP with NMO applied

Conventional Stack

Eigen Stack

Model Trace

Model TracePrincipal Component input traces


Overheadchap 11- 28

Build the Eigen Stack External Model

Editing Flow: 41- External Mod - Eigen Stack


Disk Data Input

Select dataset ---------------- temp - input to correlation (1)



Select dataset -----------------temp - input to correlation (2)

Trace read option ------------------------------------------- Get AllInline Sort

Select new PRIMARY sort key ----------------------------- CDP

Select new SECONDARY Sort Key ------------------OFFSET

Maximum traces per output ensemble ---------------------16

Number of traces in buffer ----------------------------------7000Eigen Stack

Mode ---------------------------------------------Output Eigenstack

Get matrix design gates from DATABASE --------------- No

SELECT Primary gate header word --------------------- CDP

SELECT Secondary gate header word ---------------NONE

SPECIFY matrix gate parameters ----------- 1:400-1200/

Type of Computations ? -------------------------------------- Real

Horizontal window width -----------------------------------------3

Number of iterations ------------------------------------------------0

Apply final datum statics after stack? -------------------YesTrace Display Label

Trace label ---------------------------------ext mod - eigen stackDisk Data Output

Output Dataset Filename-------------ext mod - eigen stack


Overheadchap 12- 1

Velocity Analysis and the VolumeViewer


• Generate and QC 3D Supergathers

• Precompute Velocity Analysis data

• Run Velocity Analysis and interact with theVolume Viewer/Editor


Overheadchap 12- 2

3D Spatial Supergather GenerationWe need to supply the inline and crosslinecenters as the analysis locations, and thenumber of inlines and crosslines at eachanalysis location.

Crossline

Inline Number

Number

5 15

20

40


Overheadchap 12- 3

Generate and QC a 5x3 Supergather

Editing Flow: 42-Velocity analysis


Disk Data Input

Select dataset -----------------------temp- input to velanal (1)

Trace read option --------------------------------------------Get AllDisk Data Insert

Select dataset -----------------------temp- input to velanal (2)

Trace read option --------------------------------------------Get AllDisk Data Output

Output Dataset Filename-------------------------------------temp

Trace sample format -------------------------------------------8 bit3D Supergather Formation*

Read data from other lines/surveys? --------------------- No

Select dataset ----------------------------------------------------temp

Presort in memory or on disk? ----------------------- memory

Maximum CDP fold ------------------------------------------------16

Minimum center inline number --------------------------------- 5

Maximum center inline number ------------------------------ 35

Inline increment -----------------------------------------------------10

Inlines to combine ----------------------------------------------------3

Minimum center cross line number ------------------------- 20

Maximum center cross line number ------------------------ 60

Crossline increment -----------------------------------------------20

Crosslines to combine ----------------------------------------------3Inline SortTrace Display


Overheadchap 12- 4

Editing Flow: 42-Velocity analysis cont


Disk Data InputlDisk Data InsertDisk Data Output3D Supergather Formation*Inline Sort

PRIMARY sort key ---------------------------------------- SG_CDP

SECONDARY sort key ----------------------------------- OFFSET

Maximum number of traces per output ----------------- 300Trace Display

Number of ENSEMBLES per screen ------------------------ 15

Header Plot Parameter ---------------------------------- OFFSET

Primary trace LABELING ------------- ILINE_NO (3d inline)

Secondary trace LABELING ---------- XLINE_NO(3d xline)


Overheadchap 12- 5

Other Supergathers to Analyze

Try using 5 inlines and 5 consecutiveCDP’s at each location.

• Minimum Line = 5• Maximum Line = 35• Increment =10• Span =5• Minimum Xline =20• Maximum Xline = 60• Inc = 20• Span = 5

Try using 1 inline and 9 consecutive CDP’sat each location.

• Minimum Line = 5• Maximum Line = 35• Increment =10• Span =1• Minimum Xline =20• Maximum Xline = 60• Inc = 20• Span = 9


Overheadchap 12- 6

Supergather Offset Distributions

Offset Distribution Comparison Plots


Overheadchap 12- 7

Precompute Velocity Analysis



3D Supergather Formation*

Select dataset ----------------------------------------------------temp

Use other parameters from before for lines and xlines

Inlines to combine ----------------------------------------------------1

Cross lines to combine ---------------------------------------------9Velocity Analysis PrecomputeDisk Data Output


Overheadchap 12- 8



3D Supergather Formation*Velocity Analysis Precompute

Number of CDPs to sum into gather -------------------------- 9

Apply partial NMO-to-binning---------------------------------Yes

Apply differential CDP mean statics-----------------------Yes

Absolute offset of first bin center ------------------------------ 0

Bin size for vertically summing offsets ----------------- 110

Maximum offset ------------------------------------------------ 4429

Minimum semblance analysis velocity ---------------- 7500

Maximum semblance analysis velocity ------------- 18000

Number of semblance calculations---------------------------50

Semblance sample rate (in ms) ------------------------------ 20

Semblance calculation window ------------------------------ 40

Number of stack velocity functions---------------------------13

Number of CDPs per stack strip---------------------------------9

Scale stacks by number of live samples summed----Yes

Method of computing velocity fctns------Top/base range

Velocity variation at time 0-------------------------------2000

Velocity variation at maximum time------------------5000

Get guide function from existing parameter table?---Yes

Velocity guide function table name----Imported ASCII

Maximum stretch mute percentage from NMO-----------30

Use absolute value of offset for stacking --------------- Yes

Maximum stretch percentage for NMO ---------------------30

Long offset moveout correction-----------------------------NoneDisk Data Output


Overheadchap 12- 9



3D Supergather Formation*Velocity Analysis PrecomputeDisk Data Output

Output Dataset Filename-------temp-velanal precompute



Overheadchap 12- 10

Velocity Analysis Flow



Disk Data Input

Select dataset ---------------------temp- velanal precompute

Trace read option ------------------------------------------------Sort


primary trace header -------------------------------------SG_CDP

secondary trace header ------------------------------------NONE

Sort order for dataset ---------------------------------------------*/Velocity Analysis

Select display DEVICE: -----------------------------This Screen

Is the incoming data Precomputed?: ----------------------Yes

Set which items are visible?------------------------------------No

Set semblance scaling and autosnap parameters?:--No

---------------------------------------------------------------------------

Display horizon(s)?: -----------------------------------------------No

Use neural network velocity picker?: -----------------------No

Interact with other processes using PD?:-----------------Yes

Get guide function from existing param. table? ---Yes

Vel. guide function table : ------imported from ascii file

---------------------------------------------------------------------------------

Maximum stretch percentage for NMO: --------------------30

Long offset moveout correction?:-------------------------NONE

Interval velocity below last knee: ------------------------------0

Table to store velocity picks: ----after resid stat b4 DMO

Copy picks to next location--------------------------------------No


Overheadchap 12- 11

Velocity Analysis Icons

•Next ensemble

•Previous ensemble

•

•Rewind

•

•Pointing Dispatcher(PD)

Your velocity picks are automatically savedto an RMS velocity ordered parameter filewhen you move from one location to thenext or Exit the program.


Overheadchap 12- 12

Using the Volume Viewer.

Editing Flow: 43 - Velocity Field QC


Volume Viewer/Editor

Work in Time or Depth---------------------------------------- Time

Unit System ------------------------------------------------Database

Surface Coordinates--------------------------------------ILN/XLN

Source of depth coordinate------------------------------ Volume

Source of surface coordinate limits------------------- Volume

--------------------------------------------------------------------------

Input Volume Type------------------ Stacking (RMS) Velocity

Select input volume--------------after resid stat b4 DMO

Velocity volume reference datum---------------------Floating

--------------------------------------------------------------------------

Display poststack seismic data ------------------------------No

--------------------------------------------------------------------------

Interact with Velocity Analysis------------------------------ Yes

Display gather locations----------------------------------------Yes


Overheadchap 12- 13

Possible Window Arrangement


Overheadchap 13 - 1

3D Dip Moveout

3D Dip Moveout (DMO) is a dip-dependentpartial migration that transforms nonzero-offset seismic data into zero offset seismicdata. This yields improved (dip independent)velocity estimates, attenuates coherentnoise, and improves lateral resolution. In thischapter we discuss how to run DMO toGathers 3D and DMO to stack 3D.

• Offset Binning Parameter QC

• DMO to Gathers 3D

• Parallel Processing Overview

• System Administration for ParallelProcessing

• Using Dipvels for Zero Dip VelocityEstimate

• DMO Stack 3D

• Trace Kill and Start Time Reset


Overheadchap 13 - 2

Offset Binning Parameter Determination

We can combine the features of XDB andDBTools to help identify the proper parameters forthe offset Binning. To visualize the problem let’sfirst generate two displays from DBTools.

1. Generate a predefined CDP fold map.

Change to a monochrome color map and choosea color of your choice.

2. Generate a 2D Crossplot from the TRC order ofOFFSET, CDP, ILN, ILN

3. Using the rectangular selection icon, select arectangle over all CDP’s but for a very narrowrange of offset.

Project this group of selected points to the CDPorder. Notice that the population is poor. Play withthe width of the selection polygon in offset untilyou get good population in CDP space within anoffset bin


Overheadchap 13 - 3

Predefined CDP Fold Map and TRC order 2DCrossplot


Overheadchap 13 - 4

Offset Binning Parameter QC

1. From XDB, generate a 3D: XYGraph fromthe TRC OPF of OFFSET, CDP, ILN.

2. Change the color table to use the tablecalled “contrast.rgb” using the Color ➛Edit and File ➛ Open pull down menus.

3. Zoom in and display 5 or 6 lines on thescreen.

offset binwidth


Overheadchap 13 - 5

Grid Overlay

You can overlay a grid on this display, resizethe bins to your proposed DMO offset binwidth to start analyzing the data for properbin width determination.

Click on the Grid ➛ Display and then onthe Grid ➛ Parametrize pull down menu

1660


Overheadchap 13 - 6

Grid Overlay

zoom window

grid lines


Overheadchap 13 - 7

Grid Overlay - Two Lines

Here we must decide on the offset binwidth. One way to do this is to measure the“half diamond” distance using the “doublefold” icon MB3 function.

You should measure values around 600 or700 ft. Given our group interval is 110 ft.Let’s try an offset bin width of 660 ft.

How wide does theoffset bin need to beto get 1 trace per CDP?

measure the“half diamond”distance


Overheadchap 13 - 8

Using 660 Ft Bins

This will yield 6 traces per CDP after 3DDMO to Gathers.

1 2 3 4 5 6


Overheadchap 13 - 9

Using 440 ft Bins

We will set the offset bin increment to 440 inorder to run through the mechanics.

It is obvious now that it would begeophysically incorrect to run the DMO toGathers with these parameters and that awidth of 880 ft. would actually be required

Min Offset = 0 Max Offset = 4400


Overheadchap 13 - 10

DMO Questions

Which velocity lines do you want toresolve in this job?

• Lines 5,15 25 and 35

Which input data files do you need toresolve these lines?

• Both superswaths

Do you want to do spatial supergathers orinline supergathers?

• Inline supergathers

Are you running on an SMP machine anddo you need to parallelize the pre-processing as well as the DMO?

• This will vary depending on where thecourse is being taught.



More DMO Questions

Have you adequately allocated scratchspace?

• This project is small and I should haveenough scratch allocated to output 4lines of 79 crosslines and 6 traces perCDP.

Are you going to parallelize the DMO?

• No parallelization will be used (dependson available hardware at the class site).



DMO to Gathers 3D Flow (1)

Editing Flow: 44-DMO to Gathers


Disk Data Input

Select dataset ----------------------------- shots - refr stat (1st)



Select dataset ----------------------------shots - refr stat (2nd)




Receiver residual static ------- SRF STATICS SGEMFX01Normal Moveout Correction




SELECT Velocity parameter file ----- after resids b4 dmoTrace Muting

SELECT mute parameter file ------ post nmo mute (bruteDMO to Gathers 3DTrace Display LabelDisk Data OutputNormal Moveout CorrectionTrace Display LabelDisk Data Output




Editing Flow: 44-DMO to Gathers (cont)


DMO to Gathers 3D


Number of worker threads --------------------------------------- 1



in-line number output sampling interval ------------------10



x-line number output sampling interval ---------------------1

Number of consecutive gathers to output at each loc --1

Typical CDP spacing in ensembles---------------------------55

Minimum offset to retain -------------------------------------------0

Maximum offset to retain ------------------------------------4400

Number of offset bins ---------------------------------------------10

Offset sampling ---------------------------------------------OFFSET

Typical mute time at largest offset ----------------------1000

Typical RMS velocity at early times ---------------------9000

Apply v(z) correctoin? ---------------------------------------------No

Amplitude and phase balancing mode ---use exponent..



Re-kill dead traces and apply stack mutes ------------- No

Size of input trace memory buffer (MB)-----------------------4

Size of stack trace memory buffer (MB) ----------------------4




The size of memory buffers parameters areavailable to maximize the efficiency of theprogram. Try to NEVER allow (stack buffer +2*input buffer) > 1/2 machine memory.

Flow Continued

Editing Flow: 44-DMO to Gathers (cont)


Trace Display Label

Trace label ------------------------------------------------nmo - dmoDisk Data Output

Output Dataset Filename -------------dmooffs - nmo - dmoNormal Moveout Correction

Direction for NMO application -----------------------INVERSE

SELECT Velocity parameter file -- ---after resids b4 dmoTrace Display Label

Trace label --------------------------------------------nmo dmo nmiDisk Data Output

Output Dataset Filename---------dmooffs - nmo dmo nmi



DMO Output Data QC

This output data would normally then gothrough velocity analysis.

We will not be using the output data. Youmay elect to QC the output data by runninga quick flow do display a few CDPensembles.



Considerations for Future Processing

Notice that all CDP’s after DMO to Gathershave the same offset distribution. This posesa couple of questions:

• What are the proper parameters forminimum offset, maximum offset andoffset increment in the Velocity AnalysisPrograms?

• How do you decide on a super-gather forvelocity analysis? Offset distribution isno longer an issue.



Parallel Processing Overview

There are actually four basic methods ofparallelization:

• Manual Parallel (simultaneous jobsubmission)

• Distributed (Network) Parallel

• SMP parallel

• Massive Parallel (multi SMP)

Parallel Processing Options and AvailabilityManualSimultaneous

DistributedUsing ParallelBegin and End

Distributedwithin themenu

SMP (Sharedmemory /threaded)

Massive SMP(multi-SMPmachines)

Executive

Processes

OK OK

Stack 3D

DMO 3D

OK OK OK OK

Migrations

FK and PS

OK

Migrations

FD and PSPC

OK OK

Mixing Panel

Tools



PVM Parallel:

This mode begins with a Parallel Begin andends with a Parallel End. The tools in-between are run concurrently on thedefined hosts.

Multiple Parallel Begin and Ends can benested if required.

The output data from all of the different“execs” running on the various machinesare brought back together to the masterProMAX flow on the master machine.



PVM Parallel options

There are two methods:

• These are Round Robin and

• First-Come-First-Serve.

Round-robin guarantees that the sort order ispreserved but may not be optimal forheterogeneous environments with a mix ofmachine speeds, or machines being utilizedby other processes, since faster machineswill tend to wait for slower ones to catch up.

First-come-first-served strategy allocateswork on a request basis. Faster machinesgenerate more requests than slower ones,and will remain busy until the task is finished.

The first-come-first-served strategy does notguarantee that the primary sort order will bemaintained. If it is important that the primarysort order be maintained in a parallel job, agood strategy is to place an Inline Sort after aparallel sequence using the first-come-first-served policy.



Threaded (or SMP) Parallel:

This mode may be run on machines thatsupport the Shared Memory architecture.

Typically these machines have multiple“nodes” or CP’s that all use the samememory.

There are tremendous performanceadvantages to these machines.

Currently only the 3D Stack, 3D DMO and3D Migration programs fully utilize the SMParchitecture.



Massive Parallel

This generally refers to running more thanone multi node SMP machinesimultaneously in the same job.

Currently only the 3D Stack and 3D DMOprograms support massive parallelism.



System Administrationfor Parallel Processing

PVM Daemon

• A PVM daemon process called “pvmd” isinitiated on all machines participating inparallel execution.

• ProMAX expects the local pvmdexecutable to reside in the file$PROMAX_HOME/sys/exe/pvmd

User environment

• In order to use the Parallel Executive onremote hosts, you must have trustedlogin privileges on all nodes of the virtualmachine.



Using DIPVELS

for Zero Dip Velocity Estimate

• In the case where the offset distributionprevents good population of offset binsfor Dmo to Gathers 3D you may elect touse the DIPVELS program to estimatethe zero dip RMS velocity field.

• You do not want to run the azimuthdependent velocity correction inconjunction with 3D DMO.

• It is common to use the DIPVELSvelocity analysis and application forNormal Moveout prior to CorrellationAutostatics. and then run DMO toGathers after residual statics applicationusing a conventional velocity field forNMO prior to DMO.



Dipvels Theory

Azimuth Dependent Velocities

Estimates velocity and dip from the stacking response of the data.

Useful for obtaining correct stacking velocities for datasets whichhave considerable dip and need residual statics

dtdt’

Stacking Velocity =VRMS

(1-sin2(alpha) * cos2(theta-phi))

alpha = dip angle -- theta=dip direction -- phi = shot-receiver azimuth

Note: Stacking velocity is trace dependent, if the shot to receiverazimuth varies within a CDP gather.



Dipvels Bin Centering Correction

3D NMO and Bin Center Corrections

CDP - BIN

Bin-Center

trace - mid point

T(0,0)

T(0,R)

3D NMO equation

T(X,R)=(T(0,0)+R*D)2

+(X/Vrms)2

-(X/VDMO)2)1/2

R= {Rx,Ry} Position Vector from bin center to the trace mid pointD= {Dx,Dy} X and Y component dip

The NMO, DMO and bin center corrections (R*D) requireknowledge of Vrms, Dx and Dy versus time and space



DMO to Stack 3D Flow (1)

Editing Flow: 45-DMO stack (rekill yes)


Disk Data Input

Select dataset ----------------------------- shots - refr stat (1st)


Select dataset ---------------------------- shots - refr stat (2nd)




Receiver residual static ------- SRF STATICS SGEMFX01Normal Moveout Correction




SELECT Velocity parameter file ----- after resids b4 dmoTrace Muting

SELECT mute parameter file ----- post nmo mute (brute)Automatic Gain ControlDMO Stack 3DTrace Display LabelDisk Data Output



DMO to Stack 3D Flow (2)

Editing Flow: 45-DMO stack (rekill yes) (cont)


DMO Stack 3D








Typical CDP spacing in ensembles---------------------------55

Maximum offset to retain ------------------------------------4500

Typical mute time at largest offset ----------------------1000

Typical RMS velocity at early times ---------------------9000



Apply final datum statics after stack? -------------------Yes

Rekill dead traces and apply stack mutes -------------Yes



Trace label ----------------------------------dmo stack rekill yesDisk Data Output

Output Dataset Filename --stack - with dmo (rekill yes)



Run DMO to Stack3D with the rekillswitch set to NO

Editing Flow: 46-DMO stack (rekill no)


Disk Data InputDisk Data InsertApply Residual StaticsNormal Moveout CorrectionTrace MutingAutomatic Gain ControlDMO Stack 3D

Rekill dead traces and apply stack mutes ---------------NoTrace Display Label

Trace label ------------------------------------dmo stack rekill noDisk Data Output

Output Dataset Filename ----stack - with dmo (rekill no)



Compare the two DMO Stack Volumes

Editing Flow: 47- Compare dmo stacks


Disk Data Input

Select dataset ---------------- Stack - dmo stack (rekill yes)Disk Data Insert

Select dataset ------------------- Stack -dmo stack (rekill no)Inline Sort

PRIMARY sort key ---------- (ILINE_NO) 3D inline number


TERTIARY sort key----(XLINE_NO) 3D crossline number


Number of traces in buffer ------------------------------------160


Sort key which controls End-of-Ensemble-----Secondary>Bandpass Filter<>Automatic Gain Control<Trace Display



Reset Stack DMO Output

Editing Flow: 48-Reset DMO stack output


Disk Data InputDatabase/Header Transfer

Disk Data InputDatabase/Header TransferTrace Kill/ReverseTrace MutingTrace Display LabelDisk Data Output



Reset DMO stack output



Disk Data Input

Select dataset -------------------------- Stack - resid stat (mrg

Trace read option -------------------------------------------- Get AllDatabase/Header Transfer

Direction of transfer --- Load FROM traces TO database


First database parm ------- CDP GEOMETRY TRC_TYPE

First header entry ----------- TRC_TYPE (Trace type) - INTDisk Data Input

Select dataset -------------------- Stack - with dmo (rekill no

Trace read option -------------------------------------------- Get AllDatabase/Header Transfer

Direction of transfer --- Load TO traces FROM database


First database parm ------- CDP GEOMETRY TRC_TYPE

First header entry ------------------------------------------ REKILLTrace Kill/ReverseTrace MutingTrace Display LabelDisk Data Output



Reset DMO stack output (cont)



Disk Data InputDatabase/Header TransferDisk Data InputDatabase/Header TransferTrace Kill/Reverse

Trace Editing MODE -------------------------------------------- Kill

Get edits from the DATABASE? ------------------------------ No

PRIMARY edit list header word ----------------------- REKILL


SPECIFY traces to be edited -------------------------------------2Trace Muting

Re-apply previous mutes ------------------------------ Re-rampTrace Display Label

Trace label ---------------------------------------dmo stack (reset)Disk Data OutputOutput Dataset Filename-----------------stack dmo stack (reset)



Trace Kill and Start Time Reset

Data moved to originallyunoccupied bins

Trace start timesbrought shallower


Overheadchap 14- 1

CDP Taper on Stack Data

CDP Taper is a post stack, premigrationamplitude tapering tool that, as well asmodifying the seismic data amplitudes,stores the scalar values in the CDPGEOMETRY Ordered Parameter Files as theTOPTAPER and BOTTAPER parameters.The top and bottom taper numbers define anamplitude ramp that is applied to each tracein the flow.


• CDP Taper Overview

• Execution of CDP Taper

• Generating QC Plots of the Taper Values


Overheadchap 14- 2

CDP Taper Overview

In most cases you will want to apply someamplitude tapering to the edge traces of a 3Dprospect prior to 3D migration.

Tapering does exist in most of the migrationprograms, but this taper is relative to thepadded edges of a rectangularized survey.

In cases where the line ends are not constantyou may still end up with amplitudediscontinuities from line to line or crossline tocrossline.

The CDP Taper program computes asmoother amplitude scaler for the edgetraces based on user specified searchwindow sizes.

The higher value of search window that isinput, the more tapering will be applied.


Overheadchap 14- 3

Example Locations

For 3D, this tool scans the CDP fold over amoving rectangular array of user definedsize, computing top and bottom tapernumbers for the center CDP in the array.

CDP Taper Example Locations

on the edge

live in the corner

dead in thecorner

one line in from the edge

first live, butnot on the edge


Overheadchap 14- 4

Example Calculations

No zero fold CDPs - taper value is 1

Some zero fold CDPs and the center CDPhas non-zero fold, the taper number iscalculated as:

Center CDP is on the edge(first/last line or first/last xline)Taper value = 0

Center CDP has fold >0Total number of CDP’s in window = 25Total number of zero fold CDP’s = 5

INT(array area/2) - number of zero fold CDPsINT(array area/2).

Taper value = (12-5)/12 = 0.58

Center CDP has fold = 0Taper Value = 0

Center CDP has fold > 0Total number of CDP’s in window = 25Total number of zero fold CDP’s = 6Taper Value = (12-6)/12 = 0.50

Using Equation

If CDP not on the edge thenTotal number of CDP’s in window = 25Total number of zero fold CDP’s = 10Taper value = (12-10)/12 = 0.17


Overheadchap 14- 5

Execution of CDP Taper

Editing Flow: 49-CDP taper


Disk Data Input

Select dataset -----------------------stack - dmo stack (reset)

Trace read option -------------------------------------------- Get AllCDP Taper

Top number of inline CDP’s ------------------------------------- 5

Top number of cross line CDP’s---------------------------------5

Bottom number of inline CDP’s----------------------------------9

Bottom number of cross line CDP’s----------------------------9Trace Display Label

Trace label --------------------------------------dmo stack (taper)Disk Data Output

Output Dataset Filename--------stack - dmo stack (taper)


Overheadchap 14- 6

Generating QC Plots

of the Taper Values

QC Plots from XDB

1. Open the Database display window

2. Select the 3D option

3. Select your area and your line and theCDP order

4. Display an XYgraph of CDP: X, Y, FOLD

5. Display an XYgraph of CDP: X, Y,TOPTAPER

6. Display an XYgraph of CDP: X, Y,BOTTAPER

7. Edit the Colorbar

Set the interpolation mode to “MANUAL”and the change the color of the first colorbox to black.

Here you can clearly see the original zerofold CDP’s in the fold plot and you can seethe traces which have been assigned ataper scaler of zero.


Overheadchap 15- 1

3D Velocity Viewer/Editor

This stand-alone tool enables you to scanthrough a 3D velocity field, identify and editvelocity control points, and analyze theinterpolation between the control points. Thistool also lets you smooth the velocity fieldand convert stacking velocities to intervalvelocities.


• 3D Velocity Viewer/Editor Overview

• 3D Velocity Viewer/Editor Execution


Overheadchap 15- 2

3D Velocity Viewer/Editor Overview

Inline view of velocity field

Locations of velocity functionsnear the viewing plane

Pulldown menus

Last time slice location

Last crossline location


Overheadchap 15- 3

Velocity Viewer Icons

• Zoom:Enables zooming of the velocity field.

• Move:Move view forward and back or up anddown.

• Rotate:Rotate to an inline, crossline, or time sliceview.

• Edit vel function:Popup another screen to display and edit aselected velocity function.

• Display Vel Scale:Display a simple velocity scale.


Overheadchap 15- 4

Time Slice View

3D Table Triangulation

The triangulation of the function locations isdefined via the Delaunay approach thatproduces the most equilateral trianglespossible.


Overheadchap 15- 5

3D Velocity Viewer Parameters

We will output two tables from thisprogram. One edited and smoothed inpreparation for FK Migration and anotherthat is an Interval Velocity as a function oftime for phase Shift 3D Migration.

Editing Flow: 50-Vel condition for mig


3D Velocity Viewer/Editor*

Select the type of field to edit --------- Stacking (RMS) vel

Do you wish to edit an existing table -------------------- yes

Select input velocity----------------------------------- “best vels”

Do you wish to specify the bounds of the field?------- No

Select output velocity database ---- smoothed for fk mig

Specify and alternative name of output INTV --------- Yes

Select output Interval velocity -------- for phase shift mig

Minimum depth (or time) -------------------------------------------0

Maximum depth (or time) ------------------------------------------0


Overheadchap 15- 6

Edit and Smooth the RMS Velocity

for FK Migration

1. Click on the Edit Icon and move the cursorinto the display area.

Location ofvelocity functionbeing edited

Location of

velocityfunction usedas referencefor plot onright side.

additional

Velocity functionbeing edited(circles markcontrol points)

Additionalfunctionused asreference

Conversion of velocitybeing edited to interval velocity(two different conversionmethods are being used)

Edit Icon


Overheadchap 15- 7

Editing Icons

• Zoom:Enables zooming of the velocity field.

• Picking Tool:Edit velocity points

MB1: Edits the nearest velocity function.

MB2: Freezes a blue function that you canuse as a reference.

MB3: Delete all points at a functionlocation, and hence delete the function.

Shift MB1: Adds a new function at a certainlocation.

Anther way to think of this is to Freeze theblue curve on a function that you like withMB2 and edit the questionable functionwith MB1.


Overheadchap 15- 8

Velocity Field Gridding andSmoothing

1. Select the Modify ➛ Smooth Velocityfield pull down menu to smooth the RMSvelocity field.


Overheadchap 15- 9

Convert to Interval Velocity

1. Select the Modify ➛ Convert RMS toInterval Velocity pull down menu.

There are two choices, Constant Velocity Dixor a Smoothed Gradient Dix conversion.

For our purposes in making and intervalvelocity vs. time function we will choose theSmoothed Gradient method.

We now have two velocity fields:

• A smoothed RMS field for FK migrationand

• A smoothed Interval Velocity field forPhase Shift 3D migration.


Overheadchap 16 - 1

3D Migration

The ProMAX 3D suite of migration toolsincludes poststack time and depth migrationalgorithms.

The available migrations are

• F-K

• Finite Difference (FD) Time and Depth

• Phase Shift Time and PSPC Depth


• 3D Migration Summary

• Input Requirements for 3D Migration

• Migration Program Overviews

• 3D Migration Exercise


Overheadchap 16 - 2

3D Migration Summary

The choice of poststack migration processcan be difficult. Factors to consider whendeciding which migration to use shouldinclude the following:

• complexity of the velocity field

• steepness of dips to be imaged

• runtime

Migration Name Type Domain Velocity V(x,y) V(t/z) Dip Rel.Time

Stolt 3D F-K Time VRMS(x,y,t) Poor Poor Fair 0.9

Phase Shift 3D Phase Shift Time VINT(t) Poor Good Excel 1

Explicit FD 3D Time F-X Time VINT(x,y,t) Fair Excel Good 13

Explicit FD 3D Depth F-X Depth VINT(x,y,z) Good Excel Good 18

PSPC 3D Depth Phase Shift Depth VINT(x,y,z) Good Good Excel 5


Overheadchap 16 - 3

Input Requirements for 3D Migrations

• Input data should be a 3D paddedstacked volume, usually with DMOalready applied.

• Trace data corrected to a flat datum.

• Velocities referenced to a flat datum.

• The input stacked data must be sortedwith the primary sort of inline(ILINE_NO) and the secondary sort ofcrossline (XLINE_NO).

• You may need to use the Pad 3d StackVolume process to pad the stacked datausing ILINE_NO as the primary sort.

• With all 3D Migrations, you should beaware of the potential need for extendedscratch space.

• Explicit FD 3D Time and Explicit FD 3DDepth Migrations require that the tracespacing of the input data be equal inboth the inline and crossline directions.


Overheadchap 16 - 4

Stolt 3D Migration (Time)

Input Velocity Field Type:

• VRMS(x,y,t) (a fully variable Time/RMSvelocity field).

Pros:

• Very fast.• Excellent imaging at constant velocity.

Cons:

• Breaks down with vertical velocityvariations.

• Breaks down with lateral velocityvariations.

Tricky Parameters:

• Stolt Stretch Factor: Use 1 for constantvelocities and try 0.6 for velocities thatgradually increase with depth.

• Number of in-line/cross-line traces topad.


Overheadchap 16 - 5

Phase Shift 3D Migration (Time)


• VINT(t) (a single Time/Interval velocityfunction), or

• VINT(x,y,t) (a fully variable Time/Intervalvelocity field).

Pros:

• Fast.• Excellent handling of steep dips (up to

and > 90 degrees).• Good handling of vertical velocity

changes.

Cons:

• Breaks down with lateral velocityvariations.

Tricky Parameters:

• Number of in-line/cross-line traces topad:


Overheadchap 16 - 6

Explicit FD 3D Time Migration


• VINT(x,y,t) (a fully variable Time/IntervalVelocity field).

Pros:

• Excellent at handling vertical velocitygradients.

• Good at handling steep dips (up to 70degrees).

• Fair at handling lateral velocity changes.

Cons:

• Slow.

Tricky Parameters:

• FD Migration Algorithm"Full" is a 1 pass 3D migration, while"Split" is a 2 pass 2D migration.

• Equal CDP spacing


Overheadchap 16 - 7

Explicit FD 3D Depth Migration


• VINT(x,y,z) (a fully variable Depth/Interval Velocity field).

Pros:

• Excellent with vertically varyingvelocities.

• Good with laterally varying velocities.• Handles steep dips well (up to 70

degrees).

Cons:

• Slow.

Tricky Parameters:

• FD Migration Algorithm"Full" is a 1 pass 3D migration, while"Split" is a 2 pass 2D migration.

• Equal CDP spacing


Overheadchap 16 - 8

PSPC 3D Depth Migration


• VINT(x,y,z) (a fully variable Depth/IntervalVelocity field).

Pros:

• Fairly fast.• Excellent at handling steep dips.• Handles vertical velocity variations well.

Cons:

• Breaks down with strong lateral velocityvariations.

Tricky Parameters:

• Number of phase-shift velocities perdepth step


Overheadchap 16 - 9

Re-datum the Interval Velocities.

Editing Flow: 51- redatum velocities


Velocity Manipulation*

Type of velocity table to input --- Interval Vel in Time

Get velocity table from database? -----------------Yes

Select input velocity database entry -- for phase shift

Combine a second velocity table with the first ---- No

Resample the input velocity table(s)? ---------------No

Shift or stretch the input velocity table?----------- No

Adjust the velocities to final datum ---------------- Yes

Type of parameter table to output --- Int Vel in Time

Select output velocity database entry ----------------

------------------------------------- for ps mig - at datum

Output a single average velocity table? ------------ No

Vertically resample the output velocity table? ---- No

Adjust output velocities by percentages? ---------- No3D Velocity Viewer/Editor

Select the type of field to edit - Interval Velocity in Time

Select input velocity database entry ------------------

------------------------------------- for ps mig - at datum



3D Phase Shift Migration Flow

Editing Flow: 52- migration - phase shift


Disk Data Input

Select dataset -----------stack - dmo stack (CDP Taper)

Trace read option ---------SORT - ILINE x XLINE *:*/Phase Shift 3D Migration

Enter name of migration server host(s) ----------

Number of migration server nodes----------------------1

Select Velocity parameter file ----- for phase shift mig

Minimum/maximum in-line numbers --------------1/ 42

Minimum/maximum x-line numbers--------------- 1/ 79

Maximum migrated time --------------------------------0

Migrated time sampling interval ---------------------- 0

Minimum frequency to migrate -------------------------0

Maximum frequency to migrate -----------------------80

Number of in-line traces to pad --------------------------0

Number of cross-line traces to pad --------------------0

In-line taper length (in traces) ------------------------- 0

Cross-line taper length (in traces) --------------------- 0

Top time taper (in ms) ------------------------------- 100

Bottom time taper (in ms) -------------------------- 100

Re-apply trace mutes and rekill dead traces? -----YesTrace Display Label

Trace label -----------------------------mig - phase shiftDisk Data Output

Output Dataset Filename-------migration - phase shift


Overheadchap 17- 1

ProMAX Marine 3D Geometry

This chapter serves as an example of howyou would do the geometry assignmentsequence for marine 3D data from UKOOAdata


Overheadchap 17- 2

3D Marine Geometry

from UKOOA Data

Import a UKOOA file which is the standardoutput from navigation processing. The filecontains:

• coordinates for each shot location

• receiver coordinates for each trace ofeach shot.


Overheadchap 17- 3

Determine Primary Azimuth forBinning

You should measure a value ofapproximately 32 degrees East of North.

25 mt group int25 mt shot int50 mt line spacing32 degree azimuth


Overheadchap 17- 4

Cable Feather QC

• Press MB1 on any shot and its cable willhighlight.

• Press MB2 near a shot and all shots on thesame shot line will highlight.

• Press Shift-MB2 to clear the screen.


Overheadchap 17- 5

Midpoint Scattergram


Overheadchap 17- 6

Display the Grid and the Shots


Overheadchap 17- 7

Interactive Grid QC and Alteration

You may choose to have one subsurface linefor each surface sail line. In this case youmay elect to turn off the midpoint and shotplots and redisplay the shots only in black.

• Views ➛ Remove ➛ Shot basedPosting of Position

• Views ➛ Remove ➛ Midpoint basedPosting of Position

• Display ➛ Source ➛ Control Points ➛Black

• Grid ➛ Display


Overheadchap 17- 8

One CDP Line per Sail Line


Overheadchap 17- 9

2. Display ➛ Midpoint ➛ Control Points ➛Black :


Overheadchap 17- 10

Critical Parameters for CDP Binning

In Preparation for Flex Binning, it isCRITICAL to get the conventional CDPBinning and Offset Binning parameterscorrect.

CDP Binning Parameters Control:

• How many lines and crosslines existbefore and after Flex Binning

• In the Flex Binning assignment one ofthe parameters pertains to the number oftraces per offset bin that shouldcontribute to each CDP. Typically, this willbe set to 1 in order to stabilize the offsetcontribution to each CDP.

• The Goal of the Offset Binning is toachieve one trace per CDP per offsetbin, the same requirement for DMOprocessing. For a typical marine caseyou would specify the offset binincrement as twice the shot interval.


Overheadchap 17- 11

Marine 3D Collection Geometry

x

207 mt

25 mt group intv

near offset = 207next offset = 232

first bin center = 219.5

3182 mt

minimum offset to bin = 194.5

offset bin increment = 50

maximum offset to bin > 3219.5

maximum offset = 3182 mt

x

50 mt offset bin intv

first bin center = 219.5

3182 mt

minimum offset to bin = 194.5

offset bin increment = 50

maximum offset to bin > 3219.5use 3300 ft


Overheadchap 17- 12

Zoom of Offset vs CDP plot

with Offset Bins Overlay/


Overheadchap 17- 13

Assigning CDP Flex Binning:

Editing Flow: Assign CDP flex binning


Assign CDP Flex Binning*

Crossline overlap factor ------------------------------------------- 3

Inline overlap factor -------------------------------------------------1

Maximum number of trace/offset bin-------------------------1

Omit traces with zero weight --------------------------------- No

Limit flex binning to subset of survey --------------------- No

Apply crossline distance weighting ----------------------- Yes

Crossline distance weighting ------------------------------

---------------------------------------------0: 0-1, 52-0/3000: 0-1, 75-0/

Apply inline distance weighting ---------------------------- Yes

Inline distance weighting --------------------------0: 0-1, 6.25-0

Apply azimuth weighting rule -------------------------------- No

Apply prime line weighting ----------------------------------- Yes

Prime line weighting ------------- 0:1.0,0.1/3000:1.0,0.8/

Number of user defined rules ----------------------------- None

Verbose printout? -------------------------------------------------- No


Overheadchap 17- 14

Inline and Crossline Overlap

We will run with a crossline overlap factor of 3and an inline overlap factor of 1.

Inline Direction

Cro

sslin

e D

irect

ion

Inline Overlap Factor = 0.8

Cro

sslin

e O

verla

p Fa

ctor

= 2

.0


Overheadchap 17- 15

Inline and Crossline Distance Weights

Inline Overlap = 1Crossline Overlap=3

NearOffsets

IntermediateOffsets

FarOffsets

0

1

1

0

1

0

1

1 1

Inline Bin Size=12.5Cross Line Bin Size=50

XLine --> offset: distance - weights0: 0-1, 25-0 3175: 0-1, 75-01500: 0-1, 50-0

Inline --> offset: distance - weights0: 0-1, 6.25-0

inlinedirection

75’

25’50’

6.25’


Overheadchap 17- 16

Azimuth Weighting

Pass Azimuth 1

Pass Azimuth 2

Taper Length

Pass weight Reject weightLinearly tapered weight

Pass weight if Reciprocal Traces = ‘Yes’, otherwise reject weight

Lineraly tapered weight if Reciprocal Traces = ‘Yes’, otherwise reject weight


Overheadchap 17- 17

Prime Line Weighting

In the marine case we may elect to weighttraces by a single sail line.

All of the traces that contribute to the CDPline are examined by their S_line traceheader word. The sail line with the highestnumber of contributors is the prime sail line

You may elect to put an offset variant weightfunction based on the dominant sail linerepresented in the traces.

0: 1.0, 0.1/ 3000: 1.0, 0.9


Overheadchap 17- 18

QC plots from the XDB Databasedisplay

1. 3D: XYGRAPH: CDP: Xcoord, Ycoord,FOLD

2. 3D: XYGRAPH: CDP: Xcoord, Ycoord,FLEXFOLD

1. 3D: XYGRAPH: CDP: Xcoord, Ycoord,MINOFF

2. 3D: XYGRAPH: CDP: Xcoord, Ycoord,MAXOFF

1. 3D: XYGRAPH: CDP: Xcoord, Ycoord,MEANOFF

2. 3D: XYGRAPH: CDP: Xcoord, Ycoord,RMEANOFF

1. 3D: XYGRAPH: CDP: Xcoord, Ycoord,STDDOFF

2. 3D: XYGRAPH: CDP: Xcoord, Ycoord,RSTDDOFF


Overheadchap 17- 19

Produce QC plots from the database

Open the Database and use DBTools togenerate the following pairs of displays.

Fold:

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, FOLD, CDP (or use the predinedplot)

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, FLEXFOLD, CDP

Offsets

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, MINOFF, CDP

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, MAXOFF, CDP


Overheadchap 17- 20

Mean Offsets

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, MEANOFF, CDP

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, RMEANOFF, CDP

Standard Deviation of Offsets

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, STDDOFF, CDP

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, RSTDDOFF, CDP

Azimuth

View ➛ 2D Matrix CDP order: Xcoord,Ycoord, MEANAZTH,CDP


Overheadchap 17- 21

CDP Contribution and Null QC

There is one more set of QC plots that youmight find useful.

We already know that we have good offsetdistribution and fold but we don’t know howmany traces we have used more than onceand how many we have thrown away.

2. From the Database, generate 2D (simple)plots of the FLEXCDP#1, #2 and #3attributes from the Trace database.

Any trace that is NULL for FLEXCDP#1 didnot contribute to any CDP. Non NULL CDP’sin #2 and #3 contributed to more than 1 CDP.


Overheadchap 17- 22

Expand Flex Binning

Expand Flex Binning performs the secondstep of replicating or deleting traces per thebin assignments.

The tool finds the list of CDPs the tracecontributes to by querying the TRC databaseparameter FLEXCDPS.

If the trace contributes to no bins, it will bedeleted.

o

X

O

o

X

O

original shot andreceiver locations

shot and receiverlocations afterflex binning


Overheadchap 18- 1

ProMAX Land Swath Geometry

This chapter serves as an example of how toinput the geometry for a swath geometry. Themain items of interestare:

• ways to handle the spreads rolling on andoff the ends of the swaths and

• how to handle the cable roll between theswaths.


Overheadchap 18- 2

3D Land Swath Geometry

Receivers 1001-1154

Receivers 2001-2154

Receivers 8001-8154

shots 10001 -10153

shots 50001-50153

1

153-154


Overheadchap 18- 3

Geometry Dimensions

110’

440’

110’


Overheadchap 18- 4

Prepare the Lineand run the Spreadsheet

Make a new line, called “3D Land 5 swathzig-zag”

Use the File ➛ Setup pull down and enterthe project constants:

• Nominal Receiver Station Interval = 110ft.

• Nominal Source Station Interval = 110 ft.(or 155)

• nominal Crossline Separation = 440 ft.

• Source stations numbers are NOT basedon receiver station numbers

• This project was recorded using asurface source and the coordinatesystem is English units

Editing Flow: 01 - spreadsheet




Overheadchap 18- 5

Line Station Split and Import.

Note:

We are splitting the stationnumber into two numbers, onefor the line and the remaining forthe station along the line.


Overheadchap 18- 6

Filter, Apply and Generate a Basemap

Use the View ➛ View All ➛ Basemap pulldown menu.

MeasuretheAzimuth


Overheadchap 18- 7

Patterns Spreadsheet

We will define a basic bi-symmetric splitgeometry where we will have for any givenshot 4 live cables and 60 traces on eachcable. The shots will be between the centertwo cables and between traces 30 and 31 oneach cable. There will be no gap in the splitspread


Overheadchap 18- 8

Complete the Sources Spreadsheet

1. Return to the Sources Spreadsheet.

2. You may elect to reorder the columns ofthe spreadsheet so that the pattern andpattern shift cards appears near the Lineand Station columns for convenience.

Use theSetup➛ Order pull down andthen click on the column headers in theorder you want the to appear. Use MB2 onthe last column heading of interest.

3. For all of the shots in the first swath (on line10) we will use pattern number 1 and thenwe will shift the pattern by -29 for the firstshot and increment the pattern shift by 1for each shot.

4. Complete the pattern number and patternshift entries for all shots in all 5 swathsusing multiple Find and Fill operations.

5. When complete exit from the Sourcesspreadsheet using the File ➛ Exit pulldown.


Overheadchap 18- 9

Trace Assignment

For this example we will automaticallycompute a CDP grid and then apply the gridusing the batch CDP Binning* process.

In this case the Assignment step isperforming the following calculations:

• Computes the SIN and SRF for eachtrace and populates the TRC OPF

• Computes the Shot to Receiver Offset(Distance)

• Computes the Midpoint coordinatebetween the shot and receiver.

• Computes the Shot to Receiver Azimuth.


Overheadchap 18- 10

Spread QC after Trace Assignment


Overheadchap 18- 11



Overheadchap 18- 12

Grid Overlay for QC

Click on Grid ➛ Open and select the gridname that you saved.


Overheadchap 18- 13

Complete CDP Binning using theBatch CDP Binning Tool

This process will perform the CDP binningand Finalization steps in a batch job insteadof interactively using the spreadsheet.

Once the Binning is complete you cangenerate QC plots using the database



CDP Binning*



Overheadchap 19- 1

Land Geometry Using SPS Data

This chapter serves as an introduction to howto build a ProMAX database given SPSsurvey data.


Overheadchap 19- 2

3D Land Geometry from SPS Data

In this exercise you will import three SPS filesthat are likely output from modern recordingsystems. The files contains:

• coordinates for each shot

• coordinates for each receiver

• relationships between shot and receivers

You will load these files to fill the SIN andSRF and PAT (Patterns) spreadsheets, andcontinue with interactive binning.


Overheadchap 19- 3

Project Specifications:

• Group interval 50 m and cable spacing360 m

• Shot interval 60 m and shot line spacing400 m

• The shot lines are perpendicular to thereceiver lines.

• There are a maximum of 320 traces pershot

• The source and receiver spacing yields anatural CDP binning of 25 metersparallel to the cables and 30 metersperpendicular to the cables.

• This project was collected with surfacesources.

• There are a maximum of 320 traces pershot and a total of 215 shots.

• The general pattern is 80 traces/cableusing a symmetric split spread, rolling onand off on each end of the swaths.


Overheadchap 19- 4

SPS Project Basemap

9210192109

92149

92235

101112

9251

9

9251

3

9250

19250

7

101

217

9251

6

60m

50m

400m

360m


Overheadchap 19- 5

Setting Project Constants

From the main menu click Setup

• 50 m receiver station interval

• 60 m source station interval

• 360 m crossline separation

• The source stations are not based on thereceiver station numbers.

• These data were recorded using asurface source and the measurementsystem is metric.

We will measure the azimuths on abasemap generated from the receiversspread sheet.

Note:

Note that the Assignment mode isset to the third option of Matchingline and station numbers in theSIN and PAT spreadsheet


Overheadchap 19- 6

Measure the Project Azimuth

Generate a basemap of the project byopening the Receivers Spreadsheet andselecting View ➛ View All ➛ Basemap .

You should measure a value of approximately97.5 degrees East of North.

Go back the Setup window and enter the97.5o azimuth for both the shots andreceivers.


Overheadchap 19- 7

Trace Assignment

In the main menu, click on Bin.

The Assignment step is:

• Computing the SIN and SRF for eachtrace and populating the TRC OPF

• Computing the Shot to Receiver Offset(Distance)

• Computing the Midpoint coordinatebetween the shot and receiver.

• Computing the Shot to ReceiverAzimuth.


Overheadchap 19- 8

Spread QC after Trace Assignment

Open the Receiver Spreadsheet andgenerate a basemap using the View ➛ ViewAll ➛ Basemap pull down menu.


Overheadchap 19- 9

Automatic Bin Calculation and QC

Select to “Bin midpoints” and click on OK.You should get the following window.

Set the Azimuth=97.5, Grid Size in X = 30,Grid size in Y=25, Bin Space Name, OffsetBin Increment=50 and select to set theInlines to be parallel to grid Y axis.

Click on the “Calc Dim” Button


Overheadchap 19- 10

QC the Calculated Grid


Click on Grid ➛ Open and select the gridname that you saved from the Calc Dimoperation.


Overheadchap 19- 11

Complete CDP Binning

using the Batch CDP Binning Tool

1. Build and execute the following flow:

This process will perform the CDP binningand Finalization steps in a batch job insteadof interactively using the spreadsheet.

Once the Binning is complete you cangenerate the QC plots usingthe database display tools.



CDP Binning*



Documents

ProMAX 3D User Training Manual - pudn.comread.pudn.com/downloads272/sourcecode/math/1240848/promax3dhead.pdf · ProMAX 3D Seismic Processing and Analsysis: - pg 3. Overhead chap 1-