Applied Subsurface Geological Mapping with Structural Methods

Cover
CONTENTS
FOREWORD
PREFACE
ACKNOWLEDGMENTS
	Reviewers
	Contributors
	Drafting
	Support Personnel
	Contributing Authors
	Special Recognition
	Special Recognition
	Biography
	Biography
CHAPTER 1 INTRODUCTION TO SUBSURFACE MAPPING
	TEXTBOOK OVERVIEW
	THE PHILOSOPHICAL DOCTRINE OF ACCURATE SUBSURFACE INTERPRETATION AND MAPPING
	TYPES OF SUBSURFACE MAPS AND CROSS SECTIONS
CHAPTER 2 CONTOURING AND CONTOURING TECHNIQUES
	INTRODUCTION
	THREE-DIMENSIONAL PERSPECTIVE
	RULES OF CONTOURING
	METHODS OF CONTOURING BY HAND
	COMPUTER-BASED CONTOURING CONCEPTS AND APPLICATIONS
		Surface Modeling
		Steps Involved in Gridding
		Conformable Geology and Multi-Surface Stacking
		Contouring Faulted Surfaces on the Computer
CHAPTER 3 DIRECTIONALLY DRILLED WELLS AND DIRECTIONAL SURVEYS
	INTRODUCTION
	APPLICATION OF DIRECTIONALLY DRILLED WELLS
	COMMON TYPES OF DIRECTIONALLY DRILLED WELLS
		General Terminology
		Horizontal Wells
	DIRECTIONAL WELL PLAN
	DIRECTIONAL TOOLS USED FOR MEASUREMENTS
		Magnetic Surveys
		Nonmagnetic Surveys
	DIRECTIONAL SURVEY CALCULATIONS
	DIRECTIONAL SURVEY UNCERTAINTIES
	DIRECTIONAL WELL PLOTS
CHAPTER 4 LOG CORRELATION TECHNIQUES
	INTRODUCTION
		General Log Measurement Terminology
	ELECTRIC LOG CORRELATION PROCEDURES AND GUIDELINES
	CORRELATION TYPE LOG
	ELECTRIC LOG CORRELATION — VERTICAL WELLS
		Log Correlation Plan
		Basic Concepts in Electric Log Correlation
		Faults Versus Variations in Stratigraphy
		Pitfalls in Vertical Well Log Correlation
	ELECTRIC LOG CORRELATION — DIRECTIONALLY DRILLED WELLS
		Log Correlation Plan
		Correlation of Vertical and Directionally Drilled Wells
		Estimating the Missing Section for Normal Faults
		MLT, TVDT, TVT, and TST
	ELECTRIC LOG CORRELATION — HORIZONTAL WELLS
		Direct Detection of Bed Boundaries
		Modeling Log Response of Bed Boundaries and Fluid Contacts
		True Vertical Depth Cross Section
		True Stratigraphic Depth Method
	COMPUTER-BASED LOG CORRELATION
		Well Log Correlation: The Transition from Paper-Based to Screen-Based
		On-Screen Log Correlation
		Example of Unconformity Identification
		Example of Fault Identification
	REPEATED SECTION
	ESTIMATING RESTORED TOPS
		Vertical Wells
		Deviated Wells
	UNCONFORMITIES
	ANNOTATION AND DOCUMENTATION
CHAPTER 5 INTEGRATION OF GEOPHYSICAL DATA IN SUBSURFACE MAPPING
	INTRODUCTION AND PHILOSOPHY
		Seismic Data Applied to Subsurface Interpretations
		Assumptions and Limitations
	THE PROCESS
	DATA VALIDATION AND INTERPRETATION
		Examining the Seismic Sections
		Concepts in Tying Seismic Data
		Procedures in Tying Seismic Data
		Mis-ties
	DATA EXTRACTION
		Picking and Posting
		Converting Time to Depth
	SOME FINAL THOUGHTS ON SEISMIC MAPPING
CHAPTER 6 CROSS SECTIONS
	INTRODUCTION
	PLANNING A CROSS SECTION
	STRUCTURAL CROSS SECTIONS
		Electric Log Sections
		Stick Sections
	STRATIGRAPHIC CROSS SECTIONS
	PROBLEM-SOLVING CROSS SECTIONS
	FINISHED ILLUSTRATION (SHOW) CROSS SECTIONS
	CORRELATION SECTIONS
	CROSS SECTION DESIGN
		Extensional Structures
		Diapiric Salt Structures
		Compressional Structures
		Strike-Slip Faulted Structures
	VERTICAL EXAGGERATION
	PROJECTION OF WELLS
		Plunge Projection
		Strike Projection
		Other Types of Projections
		Projection of Deviated Wells
		Projecting a Well into a Seismic Line
	CROSS SECTION CONSTRUCTION ACROSS FAULTS
	THREE-DIMENSIONAL VIEWS
		Log Maps
		Fence Diagrams
		Isometric Projections
		Three-Dimensional Reservoir Analysis Model
	CROSS SECTION CONSTRUCTION USING A COMPUTER
		Correlation Cross Sections
		Stratigraphic Cross Sections
		Structural Cross Sections
	FAULT SEAL ANALYSIS
		Fault Surface Sections Constructed by Hand
		Computer-Based Fault Seal Analysis
		Conclusions
CHAPTER 7 FAULT MAPS
	INTRODUCTION
	FAULT TERMINOLOGY
	DEFINITION OF FAULT DISPLACEMENT
	MATHEMATICAL RELATIONSHIP OF THROW TO VERTICAL SEPARATION
		Quantitative Relationship
	FAULT DATA DETERMINED FROM WELL LOGS
	FAULT SURFACE MAP CONSTRUCTION
		Contouring Guidelines
		Fault Surface Map Construction Techniques
	TYPES OF FAULT PATTERNS
		Extensional Faulting
		Compressional Faulting
	FAULT DATA DETERMINED FROM SEISMIC INFORMATION
		Seismic and Well Log Data Integration — Fault Surface Map Construction
		Seismic Pitfalls
	GROWTH FAULTS
		Estimating the Vertical Separation for a Growth Fault
		Growth-Fault Surface Map Construction
	DIRECTIONAL SURVEYS AND FAULT SURFACE MAPS
		Directional Well Pitfalls
		Fault Maps, Directional Wells, and Repeated Sections
	VERTICAL SEPARATION — CORRECTION FACTOR AND DOCUMENTATION
CHAPTER 8 STRUCTURE MAPS
	INTRODUCTION
	GUIDELINES TO CONTOURING
	SUMMARY OF THE METHODS OF CONTOURING BY HAND
	CONTOURING FAULTED SURFACES
		Techniques for Contouring Across Normal Faults
		Technique for Contouring Across Reverse Faults
	MANUAL INTEGRATION OF FAULT AND STRUCTURE MAPS
		Normal Faults
		Reverse Faults
	FAULT TRACES AND GAPS — SHORTCUTS AND PITFALLS
		Rule of 45
		Tangent or Circle Method
		New Circle Method
		Equation to Determine Radius of Circle
		Equation to Determine Heave
		Fault Gap Versus Fault Heave
	STRUCTURE MAP — GENERIC CASE STUDY
	THE ADDITIVE PROPERTY OF FAULTS
	INTEGRATION OF SEISMIC AND WELL DATA FOR STRUCTURE MAPPING
	OTHER MAPPING TECHNIQUES
		Mapping Unconformities
		Mapping Across Vertical Faults
		Top of Structure Versus Top of Porosity
		Contour Compatibility — Closely Spaced Horizons
	APPLICATION OF CONTOUR COMPATIBILITY ACROSS FAULTS
		Exceptions to Contour Compatibility Across Faults
	MAPPING TECHNIQUES FOR VARIOUS TECTONIC HABITATS
		Extensional Tectonics
		Diapiric Salt Tectonics
		Strike-Slip Fault Tectonics
		Compressional Tectonics
	REQUIREMENTS FOR A REASONABLE STRUCTURAL INTERPRETATION AND COMPLETED MAPS
		Multiple Horizon Mapping
CHAPTER 9 INTERPRETATION OF THREE-DIMENSIONAL SEISMIC DATA
	INTRODUCTION AND PHILOSOPHY
		The Philosophical Doctrine Relative to the Workstation
		Optimizing the Data
		Project Setup
		Optimizing Displays for Better Results
		Framework Interpretation and Mapping
	PLANNING, ORGANIZING AND DOCUMENTING A PROJECT
		Teamwork
		Developing a Project Plan
		Developing an Interpretation Workflow
		Organizing a Workstation Project
		Documenting Work
	FAULT INTERPRETATION
		Introduction
		Reconnaissance
		Integrating Well Control
		Fault Interpretation Strategies
		Quality-Checking Fault Surfaces in Map and Seismic Views
	HORIZON INTERPRETATION
		Selecting the Framework Horizons
		Tying Well Data
		Interpretation Strategy
		Infill Strategies
	PRELIMINARY STRUCTURE MAPPING
		Drawing Accurate Fault Gaps and Overlaps
		Gridding and Contouring
	HORIZON AND FAULT INTEGRATION ON A WORKSTATION
	CONCLUSION
CHAPTER 10 COMPRESSIONAL STRUCTURES: BALANCING AND INTERPRETATION
	INTRODUCTION
	STRUCTURAL GEOLOGY AND BALANCING
	MECHANICAL STRATIGRAPHY
	CLASSICAL BALANCING TECHNIQUES
		Volume Accountability Rule
		Area Accountability
		Bed Length Consistency
		Pin Lines
		Line Length Exercise
		Computer-Aided Structural Modeling and Balancing
		Retrodeformation
		Picking Thrust Faults
	CROSS SECTION CONSISTENCY
	CROSS SECTION CONSTRUCTION
		Busk Method Approximation
		Kink Method Approximation
		Kink Method Applications
	DEPTH TO DETACHMENT CALCULATIONS
	NONCLASSICAL METHODS
		Introduction
		Suppe’s Assumptions and Dahlstrom’s Rules
		Fault Bend Folds
		Fault Propagation Folds
		Imbricate Structures
		Box and Lift-Off Structures
		Triangle Zones and Wedge Structures
		Interference Structures
CHAPTER 11 EXTENSIONAL STRUCTURES: BALANCING AND INTERPRETATION
	INTRODUCTION
	ORIGIN OF (HANGING WALL) ROLLOVER ANTICLINES
		Coulomb Collapse Theory
		Growth Sedimentation
	A GRAPHICAL DIP DOMAIN TECHNIQUE FOR PROJECTING LARGE GROWTH FAULTS TO DEPTH
		Rollover Geometry Features
		Projecting Large Normal Faults to Depth
		Procedures for Projecting Large Normal Faults to Depth
		Determining the Coulomb Collapse Angles from Rollover Structures
	ORIGIN OF SYNTHETIC AND ANTITHETIC FAULTS, KEYSTONE STRUCTURES, AND DOWNWARD DYING GROWTH FAULTS
		Backsliding Process
	THREE-DIMENSIONAL EFFECTS AND CROSS STRUCTURES
	STRIKE-RAMP PITFALL
	COMPACTION EFFECTS ALONG GROWTH NORMAL FAULTS
		Prospect Example
		Inverting Fault Dips to Determine Sand/Shale Ratios or Percent Sand
CHAPTER 12 STRIKE-SLIP FAULTS AND ASSOCIATED STRUCTURES
	INTRODUCTION
	MAPPING STRIKE-SLIP FAULTS
		The Problem of Strike-Slip Fault Interpretation
		Strain Ellipse Model
		Problems Interpreting Stress
		Stress Measurements Across Strike-Slip Faults
	CRITERIA FOR STRIKE-SLIP FAULTING
	ANALYSIS OF LATERAL DISPLACEMENTS
		Surface Features
		Piercing Point or Piercing Line Evidence
	SCALING FACTORS FOR STRIKE-SLIP DISPLACEMENTS
	BALANCING STRIKE-SLIP FAULTS
		Compressional Folding Along Strike-Slip Faults
		Extensional Folding Along Strike-Slip Faults
	SUMMARY
	CONCLUSIONS
CHAPTER 13 GROWTH STRUCTURES
	INTRODUCTION
		Expansion Index for Growth Faults
	MULTIPLE BISCHKE PLOT ANALYSIS AND Δd/d METHODS
		Common Extensional Growth Patterns
		Unconformity Patterns
	ACCURACY OF METHOD
	EXAMPLES OF THE Δd/d METHOD
		Generic Example of a Delta
		Applying the Δd/d Method to Seismic Data
		Resolving a Log Correlation Problem
		An Example of Stratigraphic Interpretation
		Locating Sequence Boundaries in a Compressional Growth Structure
		Analysis of the Timing of a Strike-Slip Growth Structure
	THE MULTIPLE BISCHKE PLOT ANALYSIS
		MBPA to Recognize Correlation Problems
		The Use of a Stacked Multiple Bischke Plot
	VERTICAL SEPARATION VERSUS DEPTH METHOD
		Method
		Generic and Real Examples of Analysis of VS/d Plots
	CONCLUSIONS
CHAPTER 14 ISOCHORE AND ISOPACH MAPS
	INTRODUCTION
	SAND—SHALE DISTRIBUTION
	BASIC CONSTRUCTION OF ISOCHORE MAPS
		Bottom Water Reservoir
		Edge Water Reservoir
	METHODS OF CONTOURING THE HYDROCARBON WEDGE
		Limited Well Control and Evenly Distributed Impermeable Rock
		Walking Wells—Unevenly Distributed Impermeable Rock
	VERTICAL THICKNESS DETERMINATIONS
		The Impact of Correction Factors
	VERTICAL THICKNESS AND FLUID CONTACTS IN DEVIATED WELLS
	MAPPING THE TOP OF STRUCTURE VERSUS THE TOP OF POROSITY
	FAULT WEDGES
		Conventional Method for Mapping a Fault Wedge
		Mid Trace Method
	NONSEALING RESERVOIRS
	VOLUMETRIC CONFIGURATION OF A RESERVOIR
	RESERVOIR VOLUME DETERMINATIONS FROM ISOCHORE MAPS
		Horizontal Slice Method
		Vertical Slice Method
		Choice of Method
	INTRODUCTORY RESERVOIR ENGINEERING
		Reservoir Characterization
		Estimation of Reserves
		Field Production History
	INTERVAL ISOPACH MAPS
		True Stratigraphic Thickness from Well Logs
		Interval Isopach Construction Using Seismic Data
APPENDIX
REFERENCES
INDEX
	A
	B
	C
	D
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	I
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	M
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