N469 The Practice and Theory of Seismic Depth Imaging: Conventional and Unconventional Plays

Course Facts

Course Code:
N469
Duration:
3 days
Type:
Classroom
CEU:
2.4 Continuing Education Units
PDH:
24 Professional Development Hours
Certificate:
Certificate Issued Upon Completion

Summary

Many petroleum companies routinely utilize pre-stack depth imaging technology in seismic processing workflows for both conventional and unconventional plays. Depth imaging provides superior results compared to time processing including accurate time-to-depth conversions for well planning, reliable velocity models for pore pressure prediction, and superior geohazard identification. Participants will become familiar with the underlying theory and current industry practices in the application of pre-stack depth imaging technology in conventional and unconventional plays through the use of case studies located in both onshore and offshore environments. 

Duration and Training Method

This 3-day course combines lectures, case history discussions and several classroom exercises.

Participants will learn to:

  1. Investigate the differences between time and depth imaging and understand the practical benefits of utilizing pre-stack seismic imaging workflows.
  2. Evaluate the various methods currently in use for pre-stack depth imaging.
  3. Investigate the influence of anisotropy in depth imaging.
  4. Demonstrate how velocity models are constructed and optimized for pre-stack depth imaging projects.
  5. Construct practical interpretation workflows to analyze sub-salt seismic data.
  6. Supervise the parameterization of pre-stack depth migration projects.

 Day I – Basic Concepts

  • Chapter 1: General Review: Time and Depth Imaging Methods
  • Chapter 2: The Theory of Post Stack and Pre-stack Depth Migration
  • Chapter 3: From Theory to Practice: Migration Parameterization
    • Basic concepts and methods in both time and depth processing
    • Analysis of wave propagation
    • Offshore sub-salt example
    • Onshore faulted section example
    • Ray based depth migration
    • Kirchhoff summation migration
    • Travel time calculation used in ray-based depth migration
    • Wave equation downward continuation
    • Wave equation imaging condition
    • One-way wave equation depth migration
    • Two-way wave equation depth migration
    • Anisotropic depth migration
    • Computer hardware using for depth imaging
    • Parameterization of depth migration algorithms
    • Depth migration operator dip
    • Depth migration aperture
    • Depth migration frequency range
    • Various types and uses of PSDM image gathers

Day II – Model Building and Depth Imaging

  • Chapter 4: Seismic Velocities and Velocity Estimation Techniques
  • Chapter 5: Anisotropy and Time-to-Depth Conversion
  • Chapter 6: Interpretation and Model Building
    • Definitions of velocity fields used in seismic processing and depth imaging
    • Velocity analysis techniques
    • Implementation of Reflection tomography
    • Implementation of Full waveform inversion
    • Time to depth conversion using pre-stack depth migration
    • Seismic to well mistie analysis and correction
    • Definition of anisotropic models
    • Wave propagation in an anisotropic media
    • Model building and depth imaging of unconventional plays
    • Estimation of fracture orientation using azimuthal anisotropy
    • Onshore conventional fault shadow example
    • Onshore unconventional shale play example
    • The link between velocity models and pre-stack depth migration results
    • Salt model building workflow
    • Models for imaging of over thrust geology
    • Fault shadows
    • Construction of anisotropic models for unconventional plays

Day III – Interpretation and Analysis

  • Chapter 7: Velocity Model and Image Quality
  • Chapter 8: Imaging and Interpretation of Sub-Salt Sediments
  • Chapter 9: PSDM Amplitudes
  • Chapter 10: Depth Imaging Projects, Workflows and Examples
    • Optimization of velocity models
    • The relation between anisotropic models and image accuracy
    • Challenges of imaging and interpretation of the subsalt section
    • Sub-salt multiples, converted waves and prism waves
    • Offshore sub-salt example
    • Onshore over thrust example
    • Ray based illumination
    • Migration illumination
    • Amplitude preserved pre-stack depth migration
    • Wave equation normalization
    • Impedance inversion using pre-stack depth migrated gathers
    • Depth imaging workflows
    • Steps for execution of depth imaging projects
    • The link between depth imaging technology and exploration and development

Who should attend

This course has been designed for seismic interpreters having both a basic understanding of the fundamentals of seismic wave propagation and some exposure to seismic data processing in time. Technical advisory staff, engineers, and supervisors having a basic understanding of seismic wave propagation will also benefit from the topics covered in this course. Course participants will be able to successfully work in a depth-imaging project, know how to differentiate signal from artifacts, understand new methods and workflows, and learn about the state-of-the-art of seismic depth imaging technology.

Prerequisites and linking courses

Participants in this course should have a basic understanding of seismic wave propagation and have some familiarity with seismic data processing. Nautilus courses N080 (Geophysics for Subsurface Professionals), N085 (Introduction to Seismic Interpretation), N443 (Essentials of Geophysics), N066 (An Objective Approach to Seismic Acquisition, Processing and Reprocessing) or equivalent training are recommended to provide an understanding of these seismic fundamentals. 

 

Click on a name to learn more about the instructor

David Kessler

Dates for this Course

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Houston

Date:
19 - 21 Oct. 2020
Event Code:
N469a20NA
Fee:
USD $3,240 (Exclusive of tax)
*Seats are currently available for NTA members only - PAYG clients will be advised as seats become available, based on the order they applied to the waitlist.

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