Structural Interpretation of Seismic Data

Trainer(s): Tim Needham
Duration: 5 days

Course objectives

  • To gain a full understanding of structures imaged by seismic.
  • To understand the formation and geometry of structures in different tectonic settings.
  • To be able to assess the impact of structures at all scales in exploration, appraisal and production settings.
  • To understand the growth and linkage of fault systems to provide the most accurate structural framework for reservoir modelling and development planning.
  • Understand the interaction of the structures with the depositional systems to improve prediction of reservoir occurrence and distribution.
  • To understand how seismic data are used in fault seal analysis.
  • To understand how seismic data are used to assess the geology of fractured reservoirs.

Course outcomes

Course participants should complete the course with a good appreciation of the above and be able to assess:

  • The workflows required for successful structural analysis and be able to apply the necessary techniques.
  • The data requirements for such studies.
  • Have an appreciation of the uncertainties involved.

Course outline

The intention is that the course is classroom based, using a mixture of lecture and practical sessions along with a discussion of software-based approaches for structural analysis. The course will include case studies and examples from all tectonic settings. The suggested course outline is:

Day 1

  • Introduction
    • Setting the scene
    • The importance of structural geology in seismic interpretation for exploration and production
    • Defining the structure
    • Techniques of structural analysis
    • Interpretation of seismic data: 2D, 3D & time-lapse
    • Limitations of seismic
    • Exercise: Alternative interpretations
  • Geomechanical analysis
    • Mechanisms of fault and fracture formation
    • Analysis of stress and strain and their applications
    • How can geomechanical concepts be used in seismic interpretation?
    • Exercise: Stress analysis and fault reactivation
  • Extensional tectonics 1
    • Fault geometry, growth & linkage
    • Interaction of faults
    • Exercise: Fault mapping and use of displacement analysis
    • Fault mapping and validation of interpretations
    • Restoration in extensional settings: 2D & 3D
    • Exercise: Fault geometry prediction
    • Case study: Fault mapping from North Sea, Algeria & NW Shelf Australia

Day 2

  • Extensional tectonics 2
    • Basin-scale faulting and uplift/subsidence analysis
    • Interpretation of basin-scale structure
    • Extension at continental margins
    • Case study: Restoration and forward modelling – North Sea & NW European margin
    • Relationship between seismic and sub-seismic scale deformation.
    • Case study: Fault population analysis from two oilfields
  • Folds and folding mechanisms
    • Fault-related folding
    • Mechanics of folding
    • Seismic interpretation of folds.
    • Analysis of curvature: applications and limitations.
    • Case study: Curvature on fold structures at subseismc and seismic scales

Day 3

  • Contractional tectonics:
    • Thrust geometries
    • Thrust-related folding
    • Interpretation techniques
    • Exercise: Section construction and thrust restoration
    • Structural restoration & forward modelling: testing the interpretation.
    • Traps and fields in contractional settings
    • Case studies: Foreland fold-thrust belts examples and histories - Moine thrust, Andean thrust belt & Zagros
    • Case studies: Deep water fold belt examples and histories – Namibia, Niger delta
  • Inversion tectonics
    • Recognition of inversion on seismic
    • Reactivation of normal faults
    • Extensional collapse on thrust faults
    • Implications for trap and seal integrity
    • Case study: Inversion in NW Europe & French Alps
    • Exercise: Inversion interpretation, SE Asia

Day 4

  • Strike slip tectonics
    • Characteristic strike-slip fault geometries
    • Recognition in seismic data
    • Fields in strike-slip settings
    • Case study: Trinidad & Assam strike-slip zones
  • Salt tectonics
    • Mechanisms of salt flow
    • Growth and geometry of salt structures in different tectonic settings
    • Allochthonous salt structures
    • Restoration of salt structures
    • Case studies: Gulf of Mexico & Zechstein basin
    • Exercise: Salt diapir seismic interpretation

Day 5

  • Fault seal analysis
    • Use of seismic data in seal analysis
    • Fluid properties for use in seal analysis
    • Fault rocks: Microstructure, permeability and control on seal capacity
    • Fault seal algorithms & calibration of fault seal estimates
    • Use in reservoir modelling
    • Dealing with uncertainty and risk
    • Case studies: NW Europe, Algeria
  • Fractured reservoirs
    • How seismic data can assist fractured reservoir analysis.
    • Recognition of fractured reservoirs & influence on reservoir performance
    • Fracture analysis & prediction using integrated multiscale data sets.
    • Case study: Kuwait

Course summary and concluding discussion.