tomostatic waveform tomography for mapleton, utah data
DESCRIPTION
Tomostatic Waveform Tomography for Mapleton, Utah data. Jianming Sheng, and Maike Buddensiek. University of Utah. Feb. 5, 2004. Outline. Motivation. Data Preprocessings. Waveform Tomogram. Summary. First-break + First-peak. 0. 2500. Depth (m). 500. m/s. 45. 0. Distances (m). 80. - PowerPoint PPT PresentationTRANSCRIPT
Tomostatic Waveform Tomography Tomostatic Waveform Tomography for Mapleton, Utah datafor Mapleton, Utah data
Jianming Sheng, and Maike Buddensiek Jianming Sheng, and Maike Buddensiek
University of UtahUniversity of Utah
Feb. 5, 2004Feb. 5, 2004
OutlineOutline
Data PreprocessingsData Preprocessings
SummarySummary
MotivationMotivation
Waveform TomogramWaveform Tomogram
First-break + First-peak First-break + First-peak
00
4545
Dep
th (
m)
Dep
th (
m)
25002500
500500
m/sm/s00 8080Distances (m)Distances (m)
MotivationsMotivations
• Produce better seismic image by Produce better seismic image by fitting waveformsfitting waveforms
ObservedObserved
PredictedPredicted
Recorded CSG # 49Recorded CSG # 49
00
0.150.15
Tim
e (s
ec.)
Tim
e (s
ec.)
2020 160160Geophone #Geophone #
168 shots168 shots168 receiver168 receiver
Interval: 5mInterval: 5m
dt: 0.5 msdt: 0.5 mslength: 1slength: 1s
OutlineOutline
SummarySummary
MotivationMotivation
Waveform TomogramWaveform Tomogram
Data PreprocessingsData Preprocessings
Data PreprocessingsData Preprocessings
• Instrument caused amplitude anomaliesInstrument caused amplitude anomalies
Amplitude Vs. TraveltimeAmplitude Vs. Traveltime
Dashed: FittedDashed: FittedSolid: ObservedSolid: Observed
4040
2020
Log
-Am
pli
tud
eL
og-A
mp
litu
de
00 0.090.09Traveltime (sec.)Traveltime (sec.)
Data PreprocessingsData Preprocessings
• Instrument caused amplitude anomaliesInstrument caused amplitude anomalies• Earth attenuationEarth attenuation
Frequency Spectrum Vs. OffsetFrequency Spectrum Vs. OffsetF
req
uen
cy (
Hz)
Fre
qu
ency
(H
z)
0.00.0
Offset (m)Offset (m) 606000100100
Attenuation CompensationAttenuation Compensation
Liao and McMechan (1997)Liao and McMechan (1997)
22 sr sf f t
Q
Centroid frequencyCentroid frequency
Spectrum Spectrum variancevariance
Attenuation factorAttenuation factor
Frequency vs. TraveltimeFrequency vs. Traveltime
8585
4040
Fre
qu
ency
(H
z)F
req
uen
cy (
Hz)
00 0.10.1Traveltime (sec.)Traveltime (sec.)
Q=24.0013Q=24.0013
Data PreprocessingsData Preprocessings
• Instrument caused amplitude anomaliesInstrument caused amplitude anomalies• Earth attenuationEarth attenuation
• Transform data to 2D formatTransform data to 2D format
i
multiplymultiply to spectrumto spectrum
multiplymultiply t for the geometrical spreadingfor the geometrical spreading
Preprocessed CSG # 49Preprocessed CSG # 49
00
0.150.15
Tim
e (s
ec.)
Tim
e (s
ec.)
2020 160160Geophone #Geophone #
Frequency Spectrum Vs. OffsetFrequency Spectrum Vs. OffsetF
req
uen
cy (
Hz)
Fre
qu
ency
(H
z)
0.00.0
Offset (m)Offset (m) 606000100100
Frequency Spectrum Vs. OffsetFrequency Spectrum Vs. OffsetF
req
uen
cy (
Hz)
Fre
qu
ency
(H
z)
0.00.0
Offset (m)Offset (m) 606000100100
OutlineOutline
SummarySummary
MotivationMotivation
Waveform TomogramWaveform Tomogram
Data PreprocessingsData Preprocessings
Misfit FunctionMisfit Function
2
0
2
00mmWddddme
s g
calsg
obssg
calsg
obssg
ConvolutionConvolution Selected receiverSelected receiver
Frazer and Sun, 1998Frazer and Sun, 1998
Waveform Tomogram Waveform Tomogram
00
4545
Dep
th (
m)
Dep
th (
m)
25002500
500500
m/sm/s00 8080Distances (m)Distances (m)
First-break + First-peak First-break + First-peak
00
4545
Dep
th (
m)
Dep
th (
m)
25002500
500500
m/sm/s00 8080Distances (m)Distances (m)
OutlineOutline
SummarySummary
MotivationMotivation
Waveform TomogramWaveform Tomogram
Data PreprocessingsData Preprocessings
SummarySummary• The waveform tomogram does not show The waveform tomogram does not show much improvement compared to the first-much improvement compared to the first- break and first-peak tomogram.break and first-peak tomogram.
• Elastic modeling code is needed.Elastic modeling code is needed.
AcknowledgmentAcknowledgment
I thank the sponsors of the 2003 UTAM I thank the sponsors of the 2003 UTAM Consortium for their financial support . Consortium for their financial support .