geoframe 4 - synthetics - exercises -...

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GeoFrame 4 - Synthetics

- Exercises -

GeoFrame 4

December 13, 2001

Copyright Notice

© 2001 Schlumberger. All rights reserved.

No part of this manual may be reproduced, stored in a retrieval system, ortranslated in any form or by any means, electronic or mechanical, includingphotocopying and recording, without the prior written permission ofSchlumberger Information Solutions, 5599 San Felipe, Suite 1700, Houston,TX 77056-2722.

Disclaimer

Use of this product is governed by the License Agreement. Schlumbergermakes no warranties, express, implied, or statutory, with respect to the productdescribed herein and disclaims without limitation any warranties ofmerchantability or fitness for a particular purpose. Schlumberger reserves theright to revise the information in this manual at any time without notice.

Trademark Information

GeoFrame™, WellPix™, WellEdit™, WellSketch™, CPS-3™ and severalother applications mentionesd in this material are trademarks ofSchlumberger.

All other products and product names are trademarks or registered trademarksof their respective companies or organizations.

Schlumberger Contents

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• • • • • •Contents

Chapter 1 About This Course

GeoFrame Synthetics Workflow. . . . . . . . . . . . . . . . . . . . . . . . .

Course Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

How to Use the Training Guide . . . . . . . . . . . . . . . . . . . . . . . . .

Common Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Typographic Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . .

Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Standard Buttons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Course Agenda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Chapter 2 Exercises

Create a Synthetic Seismogram Display. . . . . . . . . . . . Exercise

Calibrating the Sonic Log . . . . . . . . . . . . . . . . . . . . . . . Exercise

Bulk Shift, Stretch,Squeeze Time/Depth Relationship. Exercise

Statistical Wavelet Extraction. . . . . . . . . . . . . . . . . . . Exercises

Statistical Wavelet Extraction - other options . . . . . . Exercises-

Deterministic Wavelet Extraction. . . . . . . . . . . . . . . . Exercises-

Deterministic Wavelet Extraction - other options . . . Exercises-

Wavelet Dephasing in Computation Manager . . . . . . Exercises

Getting Started in WellEdit and editing well logs. . . . Exercises-

GeoFrame 4 Synthetics iii

Contents Schlumberger

iv GeoFrame 4 Synthetics

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Chapter 1

• • • • • •About This Course

Overview

This course is designed to help users learn theSyntheticsmodule and portionsof otherGeoFrameapplications, such asWellEdit , that is needed to completethe process of generating accurate synthetics. You will learn quality controtechniques for borehole paths, borehole markers, and log curve data. Youedit and correctbad logs. Working with corrected data, you will learn how tocreate a synthetics work panel incorporating logs, seismic, interpretation atops, and extract wavelets from the seismic data.

GeoFrame 3.8 IESX Synthetics Chapter 1 - 1

About This Course Schlumberger

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GeoFrame Synthetics Workflow

The workflow for this course is illustrated in Figure 1.1. Workflow progressioand chapter titles corresponding to each stage of the workflow are shown

Figure 1.1 GeoFrame Synthetics workflow

Create Project

QC Log Data

Calibrate SonicLog

Build SyntheticsDisplay

Create, Extractand ApplyWavelets

Phase Rotate orShift Seismic

Data

Lesson 7 - QC and Edit Log Data

Lesson 1 - Select, Create andEdit a Layout, Generate and Save a

Lesson 2 - Velocity Survey andSonic Calibration

Lesson 3 - Manipulate theTime/Depth Relationship

Lesson 4 - Analytical and TimeVariant Wavelets

Lesson 5 - Wavelet Extraction

Lesson 6 - Wavelet Editing

Synthetic Seismogram

Chapter 1 - 2 GeoFrame 3.8 IESX Synthetics

Schlumberger About This Course

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Course Objectives

After completing this course, you will be able to:

• Create a customized synthetic seismogram display

• Calibrate a sonic log

• Create analytical and time variant wavelets

• Extract a wavelet from the seismic data

• Use theWavelet Editing module

• Understand theDraw/Erase andFilter/Despike modes of theWellEdit module

This training manual contains certain conventions to make the manual eato use. The following sections describe the standards you will encounterthroughout the training guide.



ions

How to Use the Training Guide

Certain conventions in this guide make it easier to use. The following sectdescribe the conventions used throughout the training guide.

Common Commands

The following table describes the most common commands you willencounter throughout the exercise and training guides.

Command Generally Refers to Action Required Example

Click Buttons or objects in awindow or dialog box

Position the cursor overthe button or object andclick the left mousebutton once.

Click Start .

Right click Right Mouse Button(MB3)

Position the mousecursor over a button orother area of a window,and click the right mousebutton.

Right click theField icon to openthe Insert Structuredialog box.

Double-click Items in a window ordialog box

Position the cursor overthe item and click the leftmouse button twicerapidly.

Double-click thelocation name toopen the LocationEditor.

Drag Cursor 1. Position the mousecursor over aspecified area of awindow.

2. Press and hold theleft mouse button.

3. Drag the cursor toanother area of thewindow.

Drag the cursorfrom 7000 to 7500feet.

Enter Text fields 1. Position the cursorover the text field.

2. Click the left mousebutton once toactivate the field.

3. Type the desiredtext.

Enter the itemnumber.



Open Windows and dialogboxes

Select the appropriatemenu option or click theappropriate button orobject to display thedesignated window.

Open the Printwindow.

Press Keys on the physicalkeyboard

Press the designatedkey.

Press F9.

Select Menus and menuitems in a window

1. Position the cursorover the menu.

2. Click the left mousebutton once. A droplist appears.

3. Move the cursor tothe desired menuitem.

4. Click the left mousebutton once.

Select File > New .

Select Drop lists 1. Position the cursorover the arrow to theleft of the drop listfield.

2. Click the left mousebutton once on thearrow to display thedrop list items.

3. Move the cursorover the item to beselected. Click theleft mouse buttononce to select theitem.

Select a locationfrom the drop list.

Type Entries Text fields

(An entry to be typedappears in boldcourier font).

1. Position the cursorover the text field.

2. Click the left mousebutton once toactivate the field.

3. Type the desiredtext.

1. Type the pathand file namein theDatabasefield.

2. Enter MARGforFormation top .

3. Type SECTION1 in the Namefield.

Command Generally Refers to Action Required Example



ut

Typographic Conventions

The following table lists the special formatting you will encounter throughothe training and exercise guides.

Item Shown As Description Example

ImportantInformation

Italic text Highlightsimportantinformation withinthe text

Always enter the datein the format MM-DD-YY.

Typed Entries Bold text, courier font Indicates thespecificinformation youmust type into afield or commandline

Type 112298 in theDate field.

Buttons, menuand menuitem names,keyboard keys

Bold text Highlights itemson the window orbuttons on thekeyboard withwhich you mustinteract

1. Click Ok.

2. Select File > New.

3. Press Tab.

Mousecommandand/or keycombinations

Keyboard key name(s)and/or mousecommand separatedby a hyphen

Indicates thecombination ofkeyboard keys ormouse action andkeyboard key youmust perform

1. Press <Alt> <F4> .

2. Control-clickWELL-O andWELL-K .

Menus andMenu Items

Menu names andmenu item name(s)separated by an arrow(>)

Indicates thesequence of menunames and menuitem(s) the usermust select

SelectXSection > Create inthe Prospect window.



File names,SystemMessages andScreen Text

Bold text, Courier font Highlights systemmessages or textthat appears in awindow

1. If you receive theerror Databasenot found ,contact the systemadministrator.

2. Exported files arestored in a userspecified directorywith a userspecified nameand a .pbfextension(PowerPlanBackup File).

SystemMessages/Screen Text

Bold text, Courier font Highlights systemmessages or textthat appears on awindow

If you receive the errorDatabase notfound , contact thesystem administrator.

Caution Text displayed in ahighlighted boxpreceded by the wordCaution.

A statement toproceed cautiouslyand avoidconditions that, ifunheeded, mayadversely affect aprocedure functionor data. Lesssevere thanWarning

Caution: Take care inapplying spatiallyvarying static mistiesbecause they can causefalse structures toappear in the seismicsection.

Warning Text displayed in ahighlighted boxpreceded by the wordWarning .

A statement ofinformation toavoid conditionsthat, if unheeded,will adverselyaffect a procedure,function, or data.More severe thanCaution

Warning: You mustenter an end date that islater than the start dateto correctly calculate theduration.

Note Italic font, preceded bythe Illustrated graphicsymbol and the wordNote

Providessupplementalinformation Note: ClickingList

Summary displays onlythe item names.


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• • • • • •



Tip Italic font, preceded bythe Illustrated graphicsymbol and the wordTip

Provides helpfulsuggestions. Oftenused in Exercises. Tip: If the user can’t tell

the difference betweenshading on or off, zoomin to see the seismicmore clearly.

Best Practice Italic font, preceded bythe Illustrated graphicsymbol and the wordsBest Practice

Provides guide toefficient work flow.

Best Practice:Thebasemap will look lesscluttered if only one zoneper layer is posted.

Buttons,Dialog boxand Windowtitles, FieldNames, andmenu options.

Noted in bold type. Highlights specificwindow and fieldnames

Click OK.

Open the Createdialog box.

Select the Edit option.


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Exercises

The exercise guide contains exercises that list specific steps for you to perand specific data to enter.

Exercises

Exercises are introduced by a description of the steps to follow. The stepsappear in a numbered list of specific actions to take and data for you to seor enter.

Create a cross section:

1. SelectXSection > Create in the Prospect window.

2. TypeSECTION 1 in theName field.

3. Click OK to confirm the entry and close theXSection Create dialog box.

Standard Buttons

Use command bar buttons to inform the system that an action or commancomplete. All dialog boxes contain one or more of the following buttons:

• OK — applies the current settings and closes dialog box

• Apply — applies the current settings

• Reset— clears any changes or entries in the dialog box without saviany information

• Default — restores the settings/information in the dialog box to thesystem default

• Cancel — cancels any unsaved changes and closes dialog box

• Close — closes dialog box

• Help — displays help on the currently-active dialog box



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Course Agenda

The following is a general outline for the course. We have included time fobrief morning and afternoon breaks, as well as time for lunch.

Morning About This Course

Lesson 1 - Select, Create, and Edit a Layout, Generate andSave a Synthetic Seismogram

Lesson 2 - Velocity Survey and Sonic Calibration

Lesson 3 - Manipulate the Time/Depth Relationship

Afternoon Lesson 4 - Analytical and Time Variant Wavelets

Lesson 5 - Wavelet Extraction

Lesson 6 - Wavelet Editing

Lesson 7 - QC and Edit Log Data


Schlumberger Exercises

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Chapter 2

• • • • • •Exercises

ExerciseExercise

Create a Synthetic Seismogram Display

Getting Started

1. FromGeonet chooseGeoFrame 4.01 > GeoFrame to open theProject Manager dialog box.

2. Choose the project assigned by the instructor, put in the passwordclick onConnect. After connection to the project selectApplicationManager.

3. When theApplication Manager dialog box opens click on theSeismic icon, to open theSeismic Catalog.

4. From theSeismic Catalogclick onSynthetics, and then clickOK .

5. When theModel Selector dialog box opens, accept theDefaultModels and clickOK .

6. This will open theGeoFrame Synthetics main window, and theBorehole Selection dialog box. From theBorehole Selection dialogbox, select the boreholeBasalt-B6. This will display aD vs. T, SonicScale, RC, Wavelet, Synthetic andSeismic Track using the defaultvalues for this borehole.

7. In theSynthetics main window selectUser > Preferences to open theGeneral Preferences dialog box.

GeoFrame 4 Synthetics Exercises - 1

Exercises Schlumberger

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8. In theGeneral Preference dialog box change theVertical Scale to 3inches/second, theTrack Extension to .5 seconds, and theBackground Color to something other than white. Make any othergeneral changes you would like to make and then clickOK .

Zoom and Unzoom the display.

1. Click on theZoom icon, and then click with MB1 and drag over thearea to be zoomed. Zoom the display again.

2. Click on theUnzoom icon to remove one of the zooms.

3. Click on theUnzoom All icon to re move all zooms.

Change the size of a track.

1. In theRC track header area move the curser towards one edge of ttrack until the curser changes to “-->|”. Then click and hold MB1 andmove the curser to make the track wider, when the track is the deswidth, release MB1, and the track will be redrawn at the new width

Relocate a track in the display.

1. Place the curser in theRC track header area and move the curser unit changes to “<=> “. Click and hold MB1, drag the track until itoverlaps the boundary between theWavelet andSynthetic tracks,release MB1. TheRC track should be redrawn between theWaveletandSynthetic tracks.

Create a New Layout and save it.

1. In theSynthetics main window, chooseFile > New Layout.

2. Click on theSelect borehole icon to open theBorehole Selectiondialog box. In theBorehole Selectiondialog box, select theCopper_6borehole. ClickOK .

3. Click on theSelect time/depth relationship icon to open theTime/Depth Selection dialog box. Select theSonic logDT.WELLEDIT and clickOK .

4. Click on theAdd sonic track icon to open theSonic/DensitySelection dialog box. Select theDT.WELLEDIT andRHOB curves.Turn on (red) the radio buttons for the Interval Velocity Log and theAcoustic Impedance log. Click OK .

5. Click theAdd a scale track icon, to add aScale track to the layout.

Exercises - 2 GeoFrame 4 Synthetics


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6. Click theAdd a marker track icon to open theMarker Selectiondialog box. Select the markersDALLAS , HOUSTON, KOBE, andPARIS. (Hold the control key down to select then.) ClickOK .

7. Click theAdd a reflection coefficient track icon to open theRCParameters dialog box. ClickOK .

8. Click theAdd a wavelet track icon to open theWavelet Selectiondialog box. Select theRicker30 wavelet. ClickOK .

9. Click theAdd a synthetic track icon to open theSyntheticGeneration dialog box. ClickOK .

10. Click theAdd reference seismic track icon to open theSeismicExtent dialog box. In theselected line type select theclosest XLine.Select the8mig class of data. ClickOK .

11. Click theAdd a cross-correlation track icon to open theCorrelationGeneration dialog box. Accept the default values and clickOK .

12. Click theAdd an auxiliary log track icon to open theAuxiliary LogCurve Selection dialog box. Select theCALI curve and clickOK .

13. From the Synthetic main window selectFile > Save Layout. Type in aName andDescription of your choice, and clickOK .

Customize the new layout in the Synthetics main window.

1. In theSynthetics main window, chooseUser > Preferences to opentheGeneral Preferences dialog box. In theVertical control type in.5 for theTrack Extension. Click OK .

2. Place the curser in theSeismic track and click MB3, selectAppearance from the popup menu. From theScale tab change theHorizontal Scale to 15, and any other changes you would like to sein the seismic data. ClickOK .

3. Repeat the same procedure for theWavelet, Synthetic, andCorrelation tracks.

4. Place the curser in theSeismic track and click MB3, selectBoreholefrom the popup menu. This will display the borehole in theSeismictrack.



5. Place the curser on the borehole in theSeismic track and click MB3,selectAppearance from the popup menu to open theBoreholeAppearance dialog box.

6. In theBorehole Appearance dialog box (borehole tab) Annotate theboreholeName at the bottom of the borehole. Change the color togreen.

7. Click theSynthetic tab in theBorehole Appearance dialog box.

8. Click onSynthetics in borehole, and selectPrimary-Ricker30-normal.

9. In theDisplay parameters area of the dialog box, changeNum.Traces to 2,Wiggle color to red, andPos. Fill color to yellow.

10. ClickOK .

11. Zoom the display between theDALLAS andHOUSTON markers.

12. In theSonic track, place the cursor on theRHOB curve and clickMB3, selectAppearance, to open theLog Curve Appearance dialogbox.

13. In theFill area of the dialog box changeFill Style to Solid, Log Fill toRight, and theFill Color to yellow. Click OK .

14. Un-zoom the display.

15. Place the curser on thePARIS marker, and click MB3. From thepopup menu, SelectAppearance to open theMarker Appearancedialog box.

16. Turn on thePost across track radio button (red), and clickOK .

17. Place the cursor on one of the horizontal grid lines and click MB3.From the popup menu, selectAppearance to bring up theGridAppearance dialog box,

18. .Change the width of theHorizontal 2 Line to the next wider value,and turn on the radio button (red)Apply across tracks (horizontalLines only). Click OK .



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19. Save the current layout to the current name (the one you previouslyin.) Click the Save current layout icon, select the name you input anclick OK . In the confirmation box, click yes to overwrite the currentlayout.

Save the Synthetic.

1. In theWavelet track, click MB3 and selectContent from the popupmenu, to open theWavelet Selection dialog box.

2. Change thePolarity of the wavelet toReverse.

3. Click OK .

4. In theSynthetics track, click MB3 and selectSave from the popupmenu, to open theSave Synthetics dialog box.

5. In theSave Syntheticsdialog box type in the Name: Copper6-Rev. In theDescription type:Ricker30, Reversepolarity .

6. Click OK .



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ExerciseExercise

Calibrating the Sonic Log

This exercise takes you through the steps required to calibrate a sonic log.exercise begins with theSynthetics window open, but with no boreholeselected.

1. In theSynthetics main window selectFile > Open Layout, to opentheLayout Selection dialog box.

2. Select the default layout and clickOK .

3. Click theSelect a different borehole icon to open theBoreholeSelection dialog box.

4. Select theDiamond 14 borehole and clickOK .

5. Click Tools > Velocity Survey to access the sonic calibration module

6. Click Select sonic at the top of theVelocity Survey screen to select asonic log, then clickOK .

7. Click Select Checkshot at the top of theVelocity Survey screen,toggle onAll checkshots, select a Diamond_14 checkshot, then clickOK .

8. With the pointer in theLogs panel, click MB3 and selectContentfrom theLogspopup window. ClickRHOB, RC from calib sonic,andInterval velocity in theAvailable curves list. The curves willdisplay in theSelected curves list. Click OK .

9. Put the pointer in theDrift curve panel. Click with MB3 and selectDelete all with MB1

10. With the pointer still in theDrift curve panel, click with MB3 andselectAdd with MB1.



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11. Using theOffset/Depth readouts at the bottom left of the screen,position the pointer atOffset 0.00, Depth 0.00 and click with MB1.The pointer is now has a rubber band attached to it.

12. Using as few points as possible, digitize a drift curve following thetrend only of the original curve. Do not attempt to follow every poin

13. Click with MB3 and selectBreak with MB1. Your new drift curvedisplays as a red dashed line.

14. ClickCalibrate. In theSonic window, a (red) calibrated curve nowoverlays the (black) original. In theDrift curve window, a blueresidual drift curve displays.

15. ClickZoom at the bottom left of the screen. Position the pointer in tSonic window, and click two points to zoom into approximately thetop 10% of the sonic log.

16. In theDrift curve window, click with MB3, and selectMove to entertheMove mode.

17. Use the vertical scroll bars to scroll down the display, observing andifferences between the raw and calibrated sonic curves. As each digitized point appears in theDrift curve window, carefully examineits location on the sonic curves. If the digitized point is not sitting onsonic log break, click the digitized point with MB1 (you are inMovemode) and move it to sit on a sonic log break. ClickCalibrate torecalibrate the input sonic log and observe the results.

18. Repeat steps 14 and 15, moving down the log. There will be minordifferences between the raw and calibrated log but this is normal.

19. After you finish calibration, clickSave Data.

20. Accept theSonic name (DT_clb) and enter a description in theSonicdescription below. Include your name and date in the description.

21. Toggle onSave calibrated sonic and toggle offSave editedcheckshots.

22. Toggle onMake calibrated sonic preferred dvt.

23. ClickSave, and confirmOK in theIESX information dialog boxes.

24. Close theVelocity Survey windows.



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25. Post some of the interpreted horizons to match posted markers.

26. Click MB3 in theDvsT track, then selectContent. Select the newlysaved calibrated sonic log and observe the favorable TWT shift of tsynthetic, reference seismic, and markers in the mainSyntheticswindow.



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ExerciseExercise

Bulk Shift, Stretch & Squeeze Time/Depth Relationship

In this exercise, you will use the interactive bulk shift and stretch/squeezefunctionality to make your synthetic tie to the seismic data.

1. In the Default layout, click theSelect a different borehole icon toopen theBorehole Selection dialog box.

2. Select the boreholeFeldspar-A8, and clickOK .

3. Click theAdd a marker track icon to open theMarker Selectiondialog box.

4. Select the markersCARACAS, DALLAS , HOUSTON, KOBE ,PARIS, andSALT; then clickOK .

5. In theSeismic track, click MB3 and selectBorehole from the popupmenu, to post the borehole.

6. Put the cursor on the borehole and click MB3. SelectAppearancefrom the popup menu to open theBorehole Appearance dialog box.

7. Click theSyntheticstab in theBorehole Appearance dialog box.SelectSynthetics in Borehole, change theWiggle color to green andthePos. Fill color to green, then clickOK .

8. Select the appropriateTime/Depth relationship in theDvsT trackusing MB3 > Content. SelectPreferred Checkshot, and clickOK .

9. ChooseTools > Bulkshift, or click theBulkshift icon. You are now inbulkshift mode.

10. Click MB1 to select theCaracas event from the log or markerinformation.

11. Click MB1 to select the seismic event at the borehole, correspondito the geological event you just selected.



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nchor theed.

12. Click theStretch/Squeeze icon.

13. To select a point at the top of the zone you want to stretch/squeezeclick with MB2 at theCARACAS event. A new anchor is added.

14. Place anchors at other locations between these two using MB2.

15. Select a point at the bottom of the zone you want to stretch/squeezThe top of the Salt marker is suggested. Click twice with MB1. Youhave now defined the zone to be altered by defining top and bottomanchors.

16. Click MB2 at the Houston marker.

17. Choose a point (depth) at the top of the Houston marker to adjust specific time, and click with MB1.

18. Move the cursor to the time at the borehole with which you wish tocorrelate that depth. The area between the second point and the atoward which you moved will be squeezed, while the area betweensecond point and the anchor from which you moved away is stretch

19. Place the cursor over theDvsT curve, click MB3 > Save.

20. Enter a name and description for the checkshot. Toggle onAnchors asCheckshot. LeaveMake Preferred Checkshot off.

21. SelectOK to save the checkshot and close the dialog.

22. Place the cursor over the synthetic track, and click MB3 > Save.

23. Enter a name and description for the synthetic. ClickSaveto save thesynthetic and close the dialog.



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ExerciseExercise

Statistical Wavelet Extraction

This exercise is based on the training class workflow and assumes theSynthetics window used for the extraction has been correctly populated wthe calibrated sonic log and density log. Suggested boreholes includeAgate_H6, Copper_6, Diamond_14, and Tourmaline_5.

1. From theSynthetics main menu, clickTools > Wavelet > Extract.

2. SelectStatistical underWavelet extraction method.

3. Click Select seismic underSeismic and RC data selection.

4. In theSeismic extent dialog box, select the appropriate survey undeAvailable surveys and the appropriate seismic class underAvailableclasses.

5. In theStart cdp/End cdp boxes, set to 20 traces either side of theborehole, as posted in theReference seismic track. For the first threesuggested boreholes, accept the default forClosest inline. ForTourmaline_5, selectClosest 2D line,and set Start cdp to 470 andEnd cdp to 510. In theStart time (ms)/End time (ms) set an intervalof no more that 500ms around the zone of interest. ClickOK .

6. UnderWavelet extraction parameters, setWavelet length (ms) to160.

7. Click Wavelet phase and setWavelet polarity to Normal andWavelet phase to Zero phase.

8. Click OK .

9. Click Extract to display a wavelet.

10. If required, click the icon to the left ofReject spectra. Clickindividual Seismic spectra in thePower versus Frequency display toreject them. The spectra display in yellow when you select them.



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11. ClickExtract . A revised wavelet appears, extracted without therejected spectra.

12. ClickSave to save the wavelet.

13. Enter a name and meaningful description (time range of extractionand clickOK . The extracted wavelet displays in the mainSyntheticswindow under the wavelet sub-panel, and is automatically convolvewith the RC series to give a set of synthetic traces.

14. ClickApply, thenClose in the mainWavelet Extraction window.



ExerciseExercise

Statistical Wavelet Extraction - other options

1. Explore the following options under Wavelet phase:

• Change the wavelet polarity

• Change the wavelet phase

2. Re-extract and apply the wavelet.



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ExerciseExercise

Deterministic Wavelet Extraction

This exercise is based on the training class workflow and assumes theSynthetics panel used for the extraction has been correctly populated withcalibrated sonic log and density log. Suggested boreholes include Agate_Copper_6, Diamond_14, and Tourmaline_5.

1. Before enteringWavelet Extraction, examine the RC series andseismic around the borehole and do the following:

• Identify a time window around the zone of interest

• Ensure there are no large reflection spikes at the top and bottom oselected window

• Avoid gates dominated by a single reflector

2. From theSynthetics main menu, clickTools > Wavelet > Extract oruse the icon.

3. SelectDeterministic underWavelet extraction method. Since youare extracting deterministically, theSelect RC button is active.

4. Click Select RCand set theStart time (msec) andEnd time (msec)to use of no more than 500ms. ClickOK .

• • • • • •

Note: **ACTIVE RC** will always be available. Optionally, if RCs for the boreholealready exist, they may be used.

5. Click Select seismic underSeismic and RC data selection.

6. In theSeismic extent dialog box, select the appropriate survey undeAvailable surveys and the appropriate seismic class underAvailableclasses.



7. In theStart cdp/End cdp boxes, set to20 traces either side of theborehole, as posted in theReference seismic track. For the first threesuggested boreholes, accept the default forClosest inline. ForTourmaline_5, selectClosest 2D line,set the Start cdp to 470 and theEnd cdp to 510. In theStart time (ms)/End time (ms) set anappropriate range of about 500ms. Click OK .

8. UnderWavelet extraction parameters, setWavelet length (ms) to160. Leave the other parameters to default.

9. UnderWavelet extraction controls, selectCorrelation and clickExtract .

10. After the wavelet displays, click Show statistics.

11. ClickClose.

12. In theWavelet extraction dialog box, clickSave to name and providea description of the deterministic wavelet, then clickOK .



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ExerciseExercise

Deterministic Wavelet Extraction - other options

Explore the following options:

1. UnderWavelet extraction controls, try each of the options underCorrelation , clicking Extract after each selection. LeaveSignal toNoise until last because it takes more time to process, accepting thdefault parameters in theSignal/Noise Log dialog.

2. UnderSelect seismic, try some of the other options.

Note: Before choosingSelect area of operation, go to the base mapand define a rectangular path around the borehole (make itapproximately 10 lines by10 cdps). SelectEdit > Seismic Areal Path> Rectangular. Save it using MB3. Return toSelect area ofoperation, toggle it on, then clickPath. Select your path, then clickOK . The path dimensions can be worked out from the detailsprovided. If it is too big, (the process takes longer with bigger areasselect another one. Select a time range of about 500ms in the zoneinterest.)

3. Save and apply your wavelets as necessary.

4. In theSynthetics main window, clickUser > Preferences and ensureUse is toggled on underDeterministic lag.



ExerciseExercise

Wavelet Dephasing in Computation Manager

This exercise is designed to take you through the workflow of dephasing awavelet inSynthetics > Tools > Wavelet > Edit, and applying the wavelet asa filter inComputation Manager. You will use one of the wavelets extractedduring the class.

1. From theSynthetics main window, clickTools > Wavelet > Edit.

2. Click the desired wavelet underAvailable wavelets.

3. In theName andDescription dialog boxes enter a new name anddescription for the wavelet so that it will be identifiable later.

4. UnderWavelet type, toggle toDephase. The wavelet changes in theviews to the left. Note the changes to the Amplitude/Time andPhase/Frequency views.

5. Enter a newName andDescription.

6. Click Create.

7. Click Close.

If you use IESX this wavelet could be used as a filter in ComputationManager.

1. From theIESX Session Manager, click Application > ComputationManager. Toggle offComputed Seismic Attributes, GeoFeatureMapping, andVariance Cube,then click OK.

2. In theComputation Manager main menu, clickFile > Survey toselect the seismic data to which to apply the filter.

3. Highlight the appropriateSurvey andInput class, restricting to a fewlines as necessary.

4. UnderAttribute Volume , enter a new name in theClass Name entrybox and a description in theDescription entry box.



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5. When satisfied, clickOK .

6. From the list ofAvailable operations, selectFilter .

7. In theFilter main menu, toggle filter types toUser defined filter. IntheUser defined filter list, click the wavelet name created in step 3above. ClickOK .

8. In theFilter main menu, clickOK . No further specifications arerequired.

9. In theComputation Manager main window, clickStart to apply thefilter to the seismic data.

10. SelectFile > Exit to close theComputation Manager.

11. View the new class of data inSeis%DV.

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Tip: In Seis%DV, select a split-screen layout so that the newly created de-phasclass of data can be viewed and compared to the original class.



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ExerciseExercise

Getting Started in WellEdit and editing well logs.

1. Select the Diamond-14 borehole to display in the main syntheticwindow.

2. Select the sonic marked DT.

3. Put the curser on the sonic curve and click MB3, selectLaunchWellEdit to open theWellEdit main window.

4. Click the Select an object in the graphic displayicon (first one onthe left). Click on the sonic curve with MB1 to select it.

5. From theWellEdit main window selectEdit > Attributes to open theCurve Attribute Editor dialog box. Change theLeft scale to 280 andtheRight scale to 0. ClickOK .

6. From theWellEdit main window selectView > Scale change to opentheVertical Scale Change dialog box. Select a scale of 1/240. ClickOK .

7. From theWellEdit main window click theEdit tab.

8. Click theDraw/Erase Mode icon (third from the left) to open theDraw/Erase Mode dialog box.

9. Highlight the top icon.

10. Edit the spike in the sonic that is at a depth of between 7800 and 78Place the cursor on the curve and click with MB1 to add new pointswhen finished click MB3 and the edited curve will be displayed.

11. Repeat the process for the spikes between 9100 and 9200, and 94and 9500 feet.

12. Save the edited curve. Click on theSave icon (last one on the right) toopen theOutput dialog box.



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13. In theOutput dialog box, changeModifiers from WELLEDIT to yourname. Change theRemarks to Edited by (your name) inwelledit .

14. ClickOK .

15. In theConfirm dialog box clickOK .

16. ChooseFile > Exit to exitWell Edit .

17. In theSyntheticsmain window, place the cursor on the sonic track anclick MB3. From the popup menu selectContent to open theSonic/Density Selection dialog box.

18. From theSelected Curves listclick on the current sonic to remove itfrom the list. From theAvailable Curves list select your edited sonic.

19. ClickOK . This will now use the edited sonic to compute a synthetic


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