Slippery Surfaces: On the Behavior of BeddingIn Development




In Development

Principal Investigator(s):

The proposed study is part of a Structural Geology Initiative at EGI designed to advance our understanding of mechanical stratigraphy and its role in hydraulic stimulation. The goal is to improve existing techniques for predicting fracture geometry with a more realistic representation of geologic heterogeneity. In particular, we are studying how hydraulic fractures interact with bedding planes to create geometric complexity. Accurate prediction of fracture geometry helps to determine the spacing of fracture stages to optimize completion efficiency

Fundamental to understanding how mechanical stratigraphy impacts hydraulic stimulation, this proposal is focused on developing criteria for the failure and slip of bedding planes. Sponsors are invited to contribute rock samples for mechanical testing of bedding plane strength and friction. In exchange for rock sample donations, EGI offers a complimentary suite of geomechanics testing including Young’s Modulus, Poisson Ratio, compressive strength, tensile strength, and compressibility.

Criteria for interaction of a propagating hydraulic fracture with an orthogonal free surface have been incorporated in fracture growth models. We are extending these models by investigating the failure and slip of bonded surfaces. Future work will incorporate local stress heterogeneity and non-orthogonal impingement. In this study, we are constructing a finite element numerical model, constrained by laboratory measurement of bedding plane strength and friction, to determine the range of boundary conditions, mechanical properties, and applied loads that result in failure of a bonded bedding plane.

  • A comprehensive written report including rationale, workflow, and discussion of results
  • Tabular and graphical summaries of numerical simulation, sensitivity to model constraints
  • Summary tables of rock mechanics data, bedding plane strength and friction