Geomechanics for Effective Shale Gas Exploitation


Description

Geomechanics plays a critical role in successfully optimising shale gas exploitation. This course can help understand the essential aspects of geomechanics in shale gas enabling an engineer or geoscientist to make better field development and operational decisions. It offers a unified approach that combines theoretical, laboratory (core testing) and field aspects of exploring unconventional reservoirs. This one-day course covers fundamentals of geomechanics as applied to shales, heterogeneity, mechanical anisotropy, and natural fractures in shale and their influence on stimulation, critical elements of a successful shale stimulation programme. Case histories are used to reinforce the concepts.

Objectives

By the end of this course participants will be to develop a better understanding of:

  • application of geomechanics in shale gas recovery
  • rock mechanical properties, rock strength and stresses
  • heterogeneity and anisotropy in shales and stimulation design

Content

Session 1: Geomechanics Fundamentals

  • Concept of stress/strain, elastic properties, Young’s modulus, Poisson’s ratio, bulk modulus, shear modulus, bulk compressibility, rock strength—UCS, tensile strength, and shear strength
  • Computation of mechanical properties and strength parameters from logs
  • Converting dynamic to static and calibrating mechanical properties
  • In-situ stresses—overburden stress, minimum and maximum horizontal stresses, estimating stresses from wire line logs, and calibration
  • Pore pressure and principle of effective stress
  • How does stress help orient wellbore and completions

Session 2: Fracturing and Stress Measurement

  • Hydraulic fracturing, how fractures are created/initiated, fracture growth/ geometry, fracture height and width, preferential direction, vertical and horizontal fracs, and frac barriers
  • Stress measurement using mini-frac/leak-off test (LOT)
  • Basic definitions of fracture gradient, break down pressure, fracture propagation pressure, closure pressure, and other terminologies used in LOT
  • Fractured reservoirs—influence of natural fractures on fracturing

Session 3: Shale Anisotropy and Heterogeneity

  • Shale heterogeneity—microscopic to core to field scale—lateral variations from well-to-well— how to evaluate it?
  • Evaluating shale anisotropy, variation in mechanical properties in vertical and horizontal directions
  • Estimating anisotropic parameters using acoustic azimuthal anisotropy (sonic scanner)

Session 4: Shale Stimulation

  • Critical elements of an effective stimulation program
  • Successful shale completion strategy and case studies
  • Introduction to microseismic and hydraulic fracturing monitoring (HFM)

Who Should Attend

This short course is intended for engineers, geoscientists, and technologists involved in exploration, drilling, completions and production in unconventional reservoirs.

Instructor

Safdar Khan

Safdar Khan is a senior geomechanics engineer with Schlumberger Canada. He has sixteen years (16) of extensive experience in various aspects of petroleum geomechanics. He is engaged on a number of unconventional reservoir geomechanics studies dealing with anisotropic/heterogeneous stress modeling, wellbore stability, and design of multi-stage hydraulic fracturing; advised clients on well placement, horizontal landing points and staging stimulations for effective drainage. Khan has written several technical papers and has taught numerous training courses on unconventional geomechanics internationally. He holds a PhD in geomechanics from University of Toronto.