Previous Talks

Wednesday, November 11th, 2009

The Mechanical Earth Model: expanding the impact of geomechanics via multi-scale, multi-discipline co-simulation with application across the upstream portfolio

Peter Connolly and Kurt Hilarides, Rock Mechanics Team, Chevron Exploration Technology Company

Abstract

Mechanical properties of clay-rich shales depend on readily measured conditions of temperature, stress state and rates of deformation, much as observed for deformation of other rock types.

An often heard adage in the oil patch is "the age of easy oil is over". This is a result of over 100 years of exploration in which the main targets have been shallow, 4 ways naturally pressured or in passive basins. As the number of these "simple reservoirs" diminishes, the on-going challenge is to extract hydrocarbons from much deeper locations where the structure and seals are less certain, the fluid pressures modified by previous exploitation and the stress state complicated by present day tectonics. The industry’s solution to these challenges is to deploy high technology across all disciplines. One area of focus is the use of Mechanical Earth Models (MEM) to make pre-drill risk predictions using log and 3D finite element (FEA) based simulations of varying levels of sophistication.

There are four key components to a successful MEM, each with their own data sources and technical requirements:
  • Material Properties. petrophysics and geomechanics derived, these typically take the form of empirical relationships between log and lab- measurements
  • Geometry: from 3D seismic interpretations and geological mapping
  • Boundary Conditions: impact of contemporary and historical regional tectonics.
  • Calibration: is an iterative process that occurs during the analysis, look-back and recycle phases. It relies heavily on information from offset wells and provides the basis for future VOI analyses.
Each component in the MEM workflow requires a series of internal and external interfacing steps the construction of which has resulted in a highly flexible process that can be modified to suit the question being asked of it.
The presentation will provide a high level overview of the MEM process and review case studies where the MEM approach has been at various scales and across upstream activities.

Speaker Biographies

Peter Connolly joined Chevron’s Rock Mechanics Team in January 2005 where his main job is Mechanical Earth Modelling using 3D finite element analysis. His work focuses on characterizing the stress and deformation state for application to exploration risking, predrill salt exist strategies; and wellbore stability in non-Andersonian stress fields. He provides general numerical modelling support and consultation and heads a research project on the in-situ characterisation of shale. Prior to CVX, He was project manager at the Geophysical Institute, University of Karlsruhe and the World Stress Map. He holds a Ph.D. in structural geology from Imperial College London and is currently an Adjunct Professor at Missouri University of Science and Technology.

W. Kurt Hilarides has worked in the upstream petroleum industry for thirty-two years. He has a Geological Engineering degree from Michigan Technological University. He has worked for Shell Oil Co., Petro-Lewis, and Tenneco Oil Co.; in domestic and international E&P geological engineering assignments. He founded and managed Integrated Geoscience Technology, Inc. from 1987 until 1999 when he joined the Chevron ETC Drilling and Completions Unit as a consultant to the Rock Mechanics Team, working on petrophysics and rock mechanics technical service and research.