Interpreting Subsurface Seismic Data

Front Cover
Interpreting Subsurface Seismic Data
Interpreting Subsurface Seismic Data
Copyright
Contents
Contributors
About the editors
1 - Introduction
1. Brief history of seismic exploration
1.1 Data acquisition and processing
1.2 Data interpretation
2. Book overview
2.1 Interpretation of seismic data in complex systems
2.2 Reprocessing of vintage 2D data
2.3 Quantitative imaging
3. Future outlook
References
1 - Interpretation of seismic data in complex systems
2 - Natural Gas Hydrate Systems
1. Gas hydrate
2. Bottom simulating reflections
3. Direct gas hydrate indicators
3.1 Velocity pull ups
3.2 Phase reversals
4. Summary
Acknowledgments
References
3 - Seismic geomorphology as a tool to explore the georesource potential of slope failures—examples from offshore N ...
1. Introduction
2. Methods
3. Slope failures in the North West Shelf of Australia
3.1 Introduction
3.2 Fault-scarp degradation complexes
3.2.1 Overview
3.2.2 External geometries
3.2.3 Internal architecture and processes of emplacement
3.3 Near seabed failures
3.3.1 Overview
3.3.2 Headwall area
3.3.3 Down slope reach and transition to mass flow
4. Concluding remarks
Acknowledgments
References
4 - Seismic facies and geobody characterization in the pre-salt rift section: the Lagoa Feia Group, Campos Basin, o ...
1. Introduction
2. Geological and tectonic settings
3. Datasets
3.1 Seismic data
3.2 Well data
3.3 Seismic velocities
4. Methods
4.1 Seismic attributes analysis
4.2 Characterization of carbonate geobodies
5. Results
5.1 Seismic facies
5.2 Facies interpretation
5.3 Mapping of carbonate geobodies
5.3.1 CGB-06
5.3.2 CGB-07
5.3.3 CGB-08
5.3.4 CGB-10
5.3.5 Other CGBs
6. Discussion
6.1 Rift Initiation Systems Tract
6.2 High Tectonic Activity Systems Tract
6.3 Low Tectonic Activity Systems Tract
7. Conclusions
Acknowledgments
References
5 - Subjective uncertainty and biases: the impact on seismic data interpretation
1. Uncertainty and biases
2. Anchoring to conceptual models
2.1 Formal definition
2.2 Plain language examples
2.3 Effect on seismic interpretation
3. Availability bias
3.1 Formal definition
3.2 Plain language examples
3.3 Effect on seismic interpretation
4. Herding
4.1 Formal definition
4.2 Plain language examples
4.3 Effect on seismic interpretation
4.4 Broader implications
5. Framing bias
5.1 Formal definition
5.2 Plain language examples
5.3 Effect on seismic interpretation
5.4 Broader implications
6. Mitigation
6.1 Training
6.2 Data use
6.3 Automatization
7. Final considerations
References
2 - Interpretation and reprocessing of legacy data
6 - The use of public vintage seismic reflection profiles: an example of data rescue from the eastern Tyrrhenian ma ...
1. Introduction and background
2. Materials and methods
2.1 Data
2.2 Workflow
2.3 Digitalization and georeferencing
2.4 SEG-Y conversion
2.5 Database construction and interpretation
3. Geological background
4. Results
4.1 Unconformities and seismic units
4.2 Seismic unit U1 (Mesozoic–Cenozoic)
4.3 Seismic unit U2 (Miocene)
4.4 Seismic unit U3 (Early Pliocene–Middle Pliocene p.p.)
4.5 Seismic unit U4 (Middle Pliocene p.p.–Pleistocene)
4.6 Reconstruction of the structural setting
5. Discussion
6. Conclusions
Acknowledgment
References
7 - Time to depth seismic reprocessing of vintage data: a case study in the Otranto Channel (South Adriatic Sea)
1. Introduction
2. Geological setting
3. Data and methods
3.1 The Mediterranean Sea project and the MS-29 line
3.2 Time reprocessing
3.2.1 Editing
3.2.2 Deghosting
3.2.3 Data interpolation
3.2.4 Multiple attenuation: SRME and WEMA
3.2.5 Q correction
3.2.6 Wavelet extraction and minimum-phase conversion
3.2.7 Surface consistent deconvolution
3.2.8 Prestack time migration
3.3 Ray-based tomography
3.4 Coherency inversion
3.5 The MS-29 velocity modeling and depth imaging
3.5.1 Starting velocity model and layer-based tomography refinement
3.5.2 The grid tomography refinement
4. Results and discussion
4.1 Results from reprocessing
4.2 Seismic interpretation
4.3 Morphological and geodynamic insights
5. Conclusions
Acknowledgments
References
8 - Imaging subsurface structures using wave equation datuming advanced seismic techniques
1. Introduction
2. Wave equation datuming technique
2.1 Formulation of the procedure
2.2 WED properties and application
3. Case studies
3.1 OBS for seismic and tsunami risk assessment offshore western Peloponnesus
3.2 Exploring the deep crust below Central Sicily
3.3 Irregular topography and lithological heterogeneities in the Tuscany Geothermal Province
3.4 Wave equation datuming and high-resolution marine surveys
3.5 Wave equation datuming and high-resolution S-wave prospecting
4. Conclusion
Exercises
Exercise 7.1
Exercise 7.2
Acknowledgments
References
3 - Quantitative seismic interpretation
9 - AVO: theory and practice
1. AVO standard equation
2. AVO measurements
3. Measurement errors
4. Anisotropy
5. Intercept-gradient crossplots
6. AVO and elastic properties
7. AVO projections
8. AVO in the impedance domain
9. Seismic χ-angles
10. Application
11. Summary
References
10 - Applications of seismic AVA inversions for petrophysical characterization of subsurface targets
1. Introduction
2. A brief introduction to Bayesian inversion
3. Nile Delta inversion example
3.1 Seismic data presentation
3.2 Calibration and validation of the rock-physics model
3.3 Target-oriented, seismic-petrophysical inversion: theoretical background
3.4 Target-oriented seismic-petrophysical inversion: field data application
3.5 Interval-oriented, seismic-petrophysical inversion: theoretical background
3.6 Interval-oriented, seismic-petrophysical inversion: field data application
4. Example of MCMC inversion applied to an onshore reflection seismic data
4.1 An overview of MCMC algorithms and of the implemented MCMC inversion
4.2 Rock-physics models calibration
4.3 Field data inversion
5. Conclusions
References
11 - Full-waveform inversion of seismic data
1. Introduction
1.1 Overview of FWI
1.2 FWI versus conventional tomography
1.3 Application to real data: requirements
1.3.1 Recoverable wavenumbers
1.3.2 Low frequencies and cycle-skipping
1.4 Underlying theory
2. Workflow and validation on a 3D field dataset
2.1 FWI workflow
2.1.1 Data preparation
2.1.2 Source preparation
2.1.3 Starting model
2.1.4 Starting frequency
2.1.5 Inversion strategy
2.2 FWI results
2.2.1 Shallow overburden
2.2.2 Intermediate depths
2.2.3 Reservoir depths
2.2.4 Shot gather comparison
2.2.5 Migrations
2.3 Summary
3. Challenges and opportunities
3.1 Crustal datasets
3.2 Land datasets
3.3 FWI at full bandwidth: interpretation game-changer
3.4 FWI and machine learning
3.5 FWI in other fields
References
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
Z
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