Reverse Time Migration(RTM)Based On Elastic Wave Modeling And Seismic Data Interpretation

声明

摘要

Abstract

Acknowledgements

Table of Contents

1 Introduction

1．1 Motivation

1．2 Background：Seismic Depth imaging，Multicomponent，Seismic Migration

1．2．1 Seismic depth imaging

1．2．2 Single component and multicomponent seismic

1．2．3 Seismic Migration

1．3 Scientific way towards hydrocarbon exploration

1．4 Field data application(Nandpur gas field，Punjab platform area：Pakistan)

1．5 Elastic wave modelling

1．6 Reverse-time Migration

1．7 Thesis Overview

2 Scientific way towards hydrocarbon exploration

2．1 Introduction

2．2 Seismic Data acquisition

2．2．1 Signal recording

2．2．2 Detection and recording of seismic waves

2．3 Seismic data processing

2．3．1 Processing sequence

2．3．2 Data refinement

2．4 Seismic interpretation

2．4．1 Approach used in interpretation

2．5 Field Data Application(Nandpur Gas Field，Pakistan)

2．5．1 Field data Used for Interpretation

2．5．2 Tectonic framework of Pakistan

2．5．3 Interpretation of Given Seismic lines

2．5．4 Synthetic Seismogram

2．5．5 Marking reflector

3．3．6 Interpretation of seismic lines o／885-kbr-264

2．5．6 Time and depth structure map

2．5．7 Geophysical well logging

3 Elastic wave modeling

3．1 Introduction

3．2 Elastic wave equations in curvilinear coordinates

3．3 Non-staggered DRP／OPT Maccormack Scheme

3．4 The non-uniform media

3．5 Implementation of free surface boundary condition

3．5．1 Physical free surface boundary condition at topographic surface

3．5．2 Traction imaging for traction derivatives

3．6 Numeric Source

3．7 Absorbing condition

3．8 Numerical Examples

3．8．1 A point reflector subsurface model(half space)

3．8．2 Modelling with a buried P-wave source

3．8．3 Elastic Wave Modelling with a surface source

3．9 Chapter summary

4 Reverse-time migration based on Elastic seismic waves

4．1 Introduction

4．2 Principles of reverse-time migration

4．2．2 Seismic waves time reversal

4．3 The wavefieid imaging principle

4．4 Reverse Time Migration with subsurface Point Reflector Model

4．4．1 Forward modelling and downgoing waves

4．4．2 Reverse-time extrapolation and upgoing waves

4．4．3 Cross-correlation and time coincidence of waves

4．5 Imaging conditions

4．5．1 Cross-correlation imaging condition without normalization

4．5．2 Source normalized cross-correlation imaging conditions

4．6 Reverse-time migration：Topography Model

4．6．1 Reverse time migration Workflow

4．6．2 Modeling experiment for Uniform model

4．6．3 Modeling experiment for real model

4．6．4 Receiver wavefield backpropagation

4．6．5 Cross-correlation of source and receiver wavefield

4．6．6 Imaging techniques to improve final RTM Results

4．7 Pre-stack reverse time migration

4．8 Reverse time migration：Two layer Model

4．9 Reverse time migration：Marmousi Model

4．9．1 Modeling experiment for Uniform model

4．9．2 Modeling experiment for real model

4．9．3 Cross-correlation of source and receiver wavefield

5 Conclusions and future Directions

5．1 Conclusions

5．2 Future Directions

References

Publications