Interferometric Multiple Interferometric Multiple Migration of UPRC Data Migration of UPRC Data

Jianhua YuJianhua Yu

University of UtahUniversity of Utah

OutlineOutline Motivation and ObjectiveObjective

Interferometric Migration:

Crosscorrelogram migration Autocorrelogram migration

ExamplesExamples

Synthetic DataSynthetic Data UPRC data UPRC data

SummarySummary

OutlineOutline Motivation and ObjectiveObjective

Interferometric Migration:

Crosscorrelogram migration Autocorrelogram migration

ExamplesExamples

Synthetic DataSynthetic Data UPRC data UPRC data

SummarySummary

IVSPWD ObjectiveIVSPWD Objective Provide Look-ahead Image Below Drill Bit Provide Look-ahead Image Below Drill Bit

Reduce Uncertainty in DrillingReduce Uncertainty in Drilling

?

ProblemProblem

No Source WaveletNo Source Wavelet

No Source Initiation TimeNo Source Initiation Time

Not Easy to Get Pilot Signal in Not Easy to Get Pilot Signal in

Deviated WellDeviated Well

Interferometric Migration

No need to know source location

No need

to know source

wavelet

No limits to deviated well

SolutionSolution

No need to know initial time

OutlineOutline

. Motivation and Objective. Motivation and Objective . . Interferometric Migration . Examples . Examples . Summary . Summary

.. Crosscorrelogram migration Crosscorrelogram migration

.. Autocorrelogram migration

Interferometric MigrationInterferometric Migration

WellWell

Drill bitDrill bit

ReceiverReceiver

Primary

Primary, Ghost and Direct WavePrimary, Ghost and Direct Wave

Direct Wave

Ghost

Free-surface related Ghost Travel Free-surface related Ghost Travel TimeTime

xgxgsgghost

''

x

g

s

g’

'sg

xgxg '

Ghost Imaging Condition Ghost Imaging Condition After Correlation of TracesAfter Correlation of Traces:

x

g

s

g’

Condition: recording data have to be dense !!

Crosscorrelogram Ghost Imaging Crosscorrelogram Ghost Imaging ConditionCondition:

xgxgghost

'

x

g

s

g’

Crosscorrelogram MigrationCrosscorrelogram Migration ågg

xgxggg'

'' )()( xm

Migrated Migrated ImageImage

Crosscorrelation Function

.. Crosscorrelogram migration Crosscorrelogram migration

.. Autocorrelogram migration

Interferometric MigrationInterferometric Migration

Free-surface related Ghost Travel Free-surface related Ghost Travel time:time:

xgxgsgghost

''

x

g

s

g’

xg

xg ' sg

'xg

x

g

s

g’

xg

xg ' sg

'xg

xgxgsgghost

'' sg

Autocorrelogram Ghost Imaging Autocorrelogram Ghost Imaging ConditionCondition:

Autocorrelogram MigrationAutocorrelogram Migration

),,()(,

..

sg

gsrrm

åx

Migrated Migrated ImageImage

Autocorrelation Function

OutlineOutline

. Motivation and Objective. Motivation and Objective . Autocorrelogram Migration . Autocorrelogram Migration Method Method . Examples . Examples . Summary . Summary

Geological ModelGeological Model

0

Dep

th (

m)

3

40X (m)

V1

V2

V4

V3

V5

V6

Velocity ModelVelocity Model0 4

0

3

Dep

th(k

m)

X(km) 0 40

3

X(km)

3.5

2.0

3.5

2.0

Interval Velocity RMS Velocity

Shot Gather and CrosscorrelogramShot Gather and Crosscorrelogram

1 2000

4

Tim

e (s

)

1 2000

4

Tim

e (s

)

Traces

CSG 10 and Master trace at 80

Traces

Shot Gather and AutocorrelogramShot Gather and Autocorrelogram

1 2000

4

Tim

e (s

)

1 2000

4

Tim

e (s

)

Traces

CSG 10

Traces

Crosscorrelogram Migration ResultsCrosscorrelogram Migration Results

1.6 2.10

2.2

Tim

e (s

)

X (km)1.6 2.1

X (km)

With primary Without primary

1.6 2.10

2.2

Tim

e (s

)

X (km)1.6 2.1

X (km)

With primary Without primary

Autocorrelogram Migration ResultsAutocorrelogram Migration Results

Acquisition SurveyAcquisition Survey

00

00 4.54.5

-5-5

East (kft)East (kft)

North

(kft)

North

(kft)

Well Rig 3C Receivers

Drill bit

10

Dep

th (

kft

)D

epth

(k

ft)

0

Main Acquisition ParametersMain Acquisition Parameters

Drill-bit Depth: 9188 ftDrill-bit Depth: 9188 ft

Offset Range: 1135-4740 ftOffset Range: 1135-4740 ft

Recording Length: 20 sRecording Length: 20 s

Sample Interval: 2 msSample Interval: 2 ms

Station Number: 10Station Number: 10

Drill-bit Data of CSG #96Drill-bit Data of CSG #961 10

0

7

Tim

e (s

)Trace Number

Main Processing StepsMain Processing Steps Trace editing and static shiftTrace editing and static shift

Frequency panel analysis and noise eliminationFrequency panel analysis and noise elimination

Amplitude balance and energy normalizationAmplitude balance and energy normalization

Velocity analysisVelocity analysis

Calculating cross- and autocorrelograms, vertical stackingCalculating cross- and autocorrelograms, vertical stacking

Cross- and Autocorelogram migrationAutocorelogram migration

Frequency Panel AnalysisFrequency Panel Analysis1 10

0

7

Tim

e (s

)

1 100

7

Tim

e (s

)

< 5 Hz 5-15 Hz

Frequency Panel AnalysisFrequency Panel Analysis1 10

0

7

Tim

e (s

)

1 100

7

Tim

e (s

)

15-25 Hz 25-40 Hz

Processed CSG 96 Part of CRG 6Processed CSG 96 Part of CRG 6

1 100

7

Tim

e (s

)

1 130.5

4.5

Tim

e (s

)

Crosscorrelogram of CSG 96 Crosscorrelogram of CSG 96

1 100

4

Tim

e (s

)

1 10 1 10

8 s 12 s 16 s

Trace No.

Autocorrelogram of CSG 96 Autocorrelogram of CSG 96

1 100

4

Tim

e (s

)

1 10 1 10

8 s 12 s 16 s

Window = 8 sWindow = 8 s

1 0.5

3.2

Tim

e (s

)T

ime

(s)

50 1 50

Window=12 sWindow=12 s

Autocorrlogram Migration ImagesAutocorrlogram Migration Images

TracesTraces TracesTraces

Window = 8 sWindow = 8 s

1 0.5

3.2

Tim

e (s

)T

ime

(s)

50 1 50

Window=12 sWindow=12 s

Crosscorrlogram Migration ImagesCrosscorrlogram Migration Images

TracesTraces TracesTraces

Acquisition Survey MapAcquisition Survey Map

Well Rig

3C Receivers

Drill bit

00

00 15001500 30003000 45004500-5000-5000

East (ft)East (ft)

Nor

th (

ft)

Nor

th (

ft)

Line ACC4

3.0

2.0

1.0T

ime

(s)

SP 1255 1235 1215

Autocorrelation Ghost Image(Corr. Window=8 sAutocorrelation Ghost Image(Corr. Window=8 s))

DrillingDrilling holehole

3.0

2.0

1.0T

ime

(s)

SP 1255 1235 1215

Crosscorrelation Ghost Image ( Corr. Window 12 s)Crosscorrelation Ghost Image ( Corr. Window 12 s)

DrillingDrilling holehole

OutlineOutline

. Objective. Objective . . Autocorrelogram Migration . Examples . Examples . Summary . Summary

SUMMARYSUMMARYCrosscorr. and autocorrelogram Crosscorr. and autocorrelogram migration works for deviated wellmigration works for deviated well

Dense recording data is necessary Dense recording data is necessary for crosscorrelation migration to for crosscorrelation migration to get good quality image get good quality image

All result are comparable to surface-All result are comparable to surface-CDP sectionCDP sectionNo source position is needed for No source position is needed for crosscorrelogram migrationcrosscorrelogram migration

SUMMARYSUMMARY

Difficulty of separating upgoing Difficulty of separating upgoing and downgoing wave can cause and downgoing wave can cause artifacts in migration imageartifacts in migration image

What’s NextWhat’s Next

Improve the method’s efficiency Improve the method’s efficiency for real-time purposefor real-time purpose

Reduced the virtual multiple and Reduced the virtual multiple and other wave’s influenceother wave’s influence

Integrated migration image of Integrated migration image of both borehole data and CDP databoth borehole data and CDP data

AcknowledgementsAcknowledgements• I greatly appreciate Union Pacific I greatly appreciate Union Pacific

Resources for donating this dataResources for donating this data

• I am grateful to the 2000 sponsors of I am grateful to the 2000 sponsors of the UTAM consortium for financial the UTAM consortium for financial supportsupport

• I also thank all of people who give I also thank all of people who give me some suggestions and help for me some suggestions and help for this workthis work