Module 0. Introduction to Unconventional Geomechanics
- A few words about Oilfield Geomechanics
- What is geomechanics? Definitions, history, relevance
Modules 1 – 2. Principles of Stress and Strain & Field Stress Measurements
- Basic of stress-strain and Mohr circles- applications on natural fractures
- Effective stress concepts, role of pore pressure
- Field stress variations, structural effects
- Stresses around boreholes
- Stress determinations
Module 3. Pore Pressure Evaluation
- Basic concepts and causes of overpressure
- Pore pressure analysis – Eaton, Bowers’, NCT, effective stress methods
- Analysis workflow
- Challenges in unconventional, field examples.
Modules 4 – 5. Mechanical Rock Behavior
- Mechanical properties, elasticity plasticity, poroelasticity, viscoelasticity.
- Failure in rocks, failure criteria
- Influence of faults and fracture, anisotropy
- Laboratory testing, measurements, interpretation
- Use of logs for mechanical properties, calibration, correlations.
Module 6. Geomechanical Modeling and Workflows
- Concepts and tools
- 1D, 2D and 3D models
- Geomechanics workflows in unconventionals
Modules 7 – 8. Hydraulic Fracturing Fundamentals
- Basic, objectives, parameters
- Frac containment, net pressure
- Injection testing, DFITs
- Horizontal wells
- Perforating, Proppants – 100 mesh and proppant transport,
- Fracturing fluids
- Role of natural fractures. Injection zone selection
Module 9. Stress Shadows: Single Frac & Multi-stage, Multi-well Effects
- Mechanics of stress shadows
- Effect on multi stages and clusters
- Multi-well stress shadows
- Tip shear stresses, Modeling examples
Module 10. Rock Fabric Characterization
- Description and quantification of rock fabric attributes – cores
- Mechanical behavior, hydraulic behavior, testing in unconventionals
- Stresses – critically stress fractures and hydraulic conductivity
- Geometry and spatial occurrence, DFN models.
- Examples of evaluation in unconventional plays
Module 11. Shale Geomechanics
- Unconventional shale plays – shale types – challenges, critical issues
- Geological scenarios for completions
- Geomechanics of interfaces – HF interaction with interfaces, effect of fracture toughness
- HF models: traditional and advanced models
- Shale properties static and dynamics examples from different plays – elastic parameters, time dependency, frictional properties
- Shale and Shale like behavior – mineralogic content, shale and flow.
- Myths to debunk – brittleness, complexity, SRV and microseismic, sand volume per lateral length
Module 12. Hydraulic Fractures (HFs) and Natural Fractures (NFs)- Operational Effects
- HFs propagation with NFs – effect of NF orientation
- Dual HF propagating in a fractured media
- Pressure Diffusion – coupled effects – stimulation benefits
- Interaction HF – NF – crossing rules.
- Influence of NF characteristics – Dense vs sparse DFN, stress anisotropy, NF connectivity, parametric studies. Modeling examples.
- Influence of operational parameters, effects of fluid viscosity, injection rates – injection time,
- Influence of the stress field and insitu pore pressure on HF behavior.
- Microseismicity response with anisotropic stresses – dry and wet MS events. Effect of initial aperture of the NFs.
Module 13. Depletion Effects & Refracs
- Depletion effects on HFs, depletion and in situ stresses.
- Parent -child evaluations, Cluster efficiency, drainage volumes
- Frac hits – types.
- Microseismic depletion delineation, Cube evaluations
- Refracturing – candidates, case histories, lessons.
- Geomechanics of refracs.
- Refracs economics, refrac activity, examples.
- Refracs methods, engineered refracs.
Module 14. Multi-well Completions
- Zipper fracs, stress perturbations, induced shear around zipper fracs
- Interaction of HFs, overlapping HFs, models
- Zipper fracs stress shadows.
- Effect of multiple well completion in fractured rock mass – sheared fabric – friction angle effect, geometry of zipper fracs. Effect on fabric stimulation.
- Sheared length, pressure diffusion.
Module 15. HF Monitoring and HF Models (extra session)
- Temperature Logs, strengths and weaknesses, procedures. Effect of wellbore and completion.
- RA logging procedures, strength and weaknesses, tracer applications
- Micro seismic monitoring – MS as a geomechanics issue. Events, field data, MS imaging, passive seismology, triggered or induced seismicity, array design, surface vs downhole, source mechanisms, SRV from MS and drainage volume.
- Tiltmeters- direct fracture monitoring, measurements, patterns, cases.
- DAS/DTS Basics, production estimations, cluster efficiency, integrated analysis.
- HF Models – advanced models fundamentals, input data, 2D models, pseudo (planar) 3D, Cell/Grid based models, lumped pseudo 3D, Fully 3D, HF reservoir simulators.