Seismic characterization of a carbonate reservoir in Tarim Basin
File(s)
Published version
Author(s)
Liu, Y
Wang, Y
Type
Journal Article
Abstract
Seismic characterization of carbonate reservoirs is a challenging
task for geophysicists because of their special depositional
environment and complex interior structures. We developed a
case study of the seismic characterization of a karstified carbonate
reservoir in the Tarim Basin, western China. The characterization
procedure is sequential and includes fault and fracture
detection, seismic facies classification, seismic impedance
inversion, and lithofacies classification. We presented a dip-steered
coherence algorithm for detecting faults and karst
fractures in the carbonate reservoir. Incorporating the dip information
improves the performance and robustness. We applied
normalized seismic segments, rather than the amplitude values,
as the input to seismic facies classification, so as to reduce the
impact of strong amplitudes, such as karst fractures, and to enable
the analysis of weak amplitudes in the background strata.
For the impedance inversion, we adopted a Fourier integral
method for fast simulation in the stochastic inversion in this karstified
carbonate reservoir. The algorithm honors the lateral
variation based on the seismic trace similarity, instead of the
lateral variogram that is commonly used in stochastic inversion.
We conducted lithofacies classification, in which we used
seismic coherence as a prior knowledge, so as to honor the fracture-
associated local lithofacies with dolomitization and to distinguish
it from limestone without dolomitization. Based on
reservoir characterization described above, we determined three
drilling wells for potential oil/gas exploration.
task for geophysicists because of their special depositional
environment and complex interior structures. We developed a
case study of the seismic characterization of a karstified carbonate
reservoir in the Tarim Basin, western China. The characterization
procedure is sequential and includes fault and fracture
detection, seismic facies classification, seismic impedance
inversion, and lithofacies classification. We presented a dip-steered
coherence algorithm for detecting faults and karst
fractures in the carbonate reservoir. Incorporating the dip information
improves the performance and robustness. We applied
normalized seismic segments, rather than the amplitude values,
as the input to seismic facies classification, so as to reduce the
impact of strong amplitudes, such as karst fractures, and to enable
the analysis of weak amplitudes in the background strata.
For the impedance inversion, we adopted a Fourier integral
method for fast simulation in the stochastic inversion in this karstified
carbonate reservoir. The algorithm honors the lateral
variation based on the seismic trace similarity, instead of the
lateral variogram that is commonly used in stochastic inversion.
We conducted lithofacies classification, in which we used
seismic coherence as a prior knowledge, so as to honor the fracture-
associated local lithofacies with dolomitization and to distinguish
it from limestone without dolomitization. Based on
reservoir characterization described above, we determined three
drilling wells for potential oil/gas exploration.
Date Issued
2017-08-16
Date Acceptance
2017-06-27
Citation
Geophysics, 2017, 82 (5), pp.B177-B188
ISSN
0016-8033
Publisher
Society of Exploration Geophysicists
Start Page
B177
End Page
B188
Journal / Book Title
Geophysics
Volume
82
Issue
5
Copyright Statement
© 2017 Society of Exploration Geophysicists. All rights reserved.
Subjects
0404 Geophysics
Geochemistry & Geophysics
Publication Status
Published
Date Publish Online
2017-08-16