Fracture Characterization

Course Duration: 5 days, including lecture-based modules and hands-on exercises

Who should attend: Exploration and development geologists, geophysicists, drilling and reservoir engineers, managers, and technical personnel

Course Level: Basic to Intermediate

Course Summary: Understanding the natural fracture system and/or aspects of induced fracture stimulation represent critical aspects of reservoir characterization. For example, a recent analysis revealed that 50% of wells drilled in a fractured reservoir system yielded only 10% of the cumulative production because of improper well placement. This course will address multiple aspects of fracture dynamics, from rock mechanic behavior and fracture theory, to characterization of paleostress versus in-situ (modern) stress field, to fractured basement, to optimal well placement, to fracture stimulation and completion techniques, to integrated fracture analysis and modeling.

You Will Learn:

• The fundamentals of the behavior of rocks, including stress and strain (including rock failure), elastic versus nonelastic deformation, brittle and ductile deformation, role of fluids, and so forth.
• To understand the role of geomechanical investigation and aspects of fracture mechanics in exploratory through drilling and completion to extraction stages.
• The diversity of datasets from which geomechanical and fracture data can be extracted, including seismic aspects, drilling parameters, core and log analyses, formation tests, etc., and how they can be integrated to provide a comprehensive geomechanical model

Course Topics and Tentative Itinerary:

• Day 1 — Fundamentals of rock mechanics and rock properties
  • Discussion of stresses (total, effective, anisotropy, orientation, etc.) and resultant strain (elastic, nonelastic, brittle, ductile, failure, etc.), and properties including elastic moduli (bulk, shear, Poisson’s ratio, etc.) and failure criteria (tensile versus shear failure, failure limits).
• • Discussion of extraction of geomechanical information through geologic time from understanding the structural system of faulting, folding, fracture development, compaction, etc.
  • Seismic investigations of current static pressure regime (e.g., velocity- and frequency-based pore pressure prediction, p- and s-wave anisotropy, shear wave splitting, nodal analysis)
  • Risk assessment of seal integrity (strata and fault seal) during exploratory stages

• Day 2 — Data Sources and Techniques
  • Well log techniques (density and acoustic logging, shear wave splitting, azimuthal [image] log analysis, including LWD analysis)
  • Core-derived measurements (p-wave anisotropy, anelastic strain recovery, microseismicity, rock strength experiments)
  • Seismic-derived measurements (velocity- and frequency-based pore pressure prediction, p- and s-wave anisotropy, shear wave splitting, nodal analysis, reservoir monitoring)
  • Other techniques, formation tests, leak-off tests, etc.

• Day 3 — Wellbore Placement and Stability
  • Optimizing wellbore placement, including inclination and azimuth, within the geomechanical system
  • Position relative to the natural fracture system and/or induced fracture system
  • Stress distribution around the wellbore, monitoring and mitigating borehole breakout and/or induced failure, and LWD imaging and mudlogging techniques
  • Finding the “sweet spots”

• Day 4 — Completion Aspects
  • Formation tests (real-time LWD and wireline), leak-off tests, mini-fracs, and pressure transient analysis
  • Hydraulic stimulation and fracturing, including techniques of stimulation, feasibility of stimulation process, fracture orientation versus wellbore orientation, and monitoring techniques (e.g., proximal well and surface tiltmeters, microseismicity and nodal analysis)

• Day 5 — Reservoir Compaction and Compressibility
  • Reservoir changes with time, including effective stress variations, reservoir compaction, subsidence
  • Mass balance approaches and passive and/or active seismic monitoring
• • Special Focused Topic on Fractured Basement
• • Examination of basement fracturing
  • Petrophysical analysis of crystalline basement rocks, including fracture mineralization

• Days 1-5 — Hands-On Exercises and Examples
  • Numerous hands-on examples and exercises will be used to reinforce key concepts throughout the course, included fractured basement, clastic, and carbonate examples, fracture stimulation examples, etc.