Construction of fractured reservoir models for flow simulation incorporating geology, geophysics, and geomechanics

Reinaldo Michelena, Chris Zahm, and James R. Gilman

Objectives

Flow models have the purpose of explaining and forecasting reservoir performance that can help plan the development and exploitation of the resource. Conventional and unconventional naturally fractured reservoirs are particularly difficult to model due to the interconnectivity of matrix and fracture properties. Unconventional reservoirs pose the additional challenge of accounting for natural fractures that can become conductive during hydraulic stimulation. This class explains the steps necessary to build fractured reservoir models using sound stratigraphic and structural frameworks, calibrated 3D seismic attributes, and geomechanical information. Models and concepts are examined in the context of how they impact fluid flow, reservoir simulation results, field production, and forecast. This 2-day course will present the workflows that have been developed along with spreadsheet-based exercises to solidify concepts. The course provides in-depth presentations and discussions of the models presented.

Course Format

The course takes place online in four consecutive 4-hour sessions.

Course Outline

Session 1

  • Natural fractured reservoirs: overview and concepts
  • Impact of natural fractures on reservoir performance: overview
  • Tight unconventional reservoirs: mechanical stratigraphy in core, well logs, and seismic
  • Tight unconventional reservoirs: use and value of outcrop analogs
  • Tight carbonate mechanical stratigraphy interpretation
  • Reservoir engineering data for of naturally fractured reservoirs

Session 2

  • Tight unconventional reservoirs: seismic properties for fracture characterization
  • Discrete vs continuum natural fracture descriptions for simulation in fractured reservoirs
  • Tight unconventional reservoirs: geomechanics review
  • Effective fracture permeability

Session 3

  • Tight unconventional reservoirs: modeling perm of reactivated fractures
  • Pressure transient response time
  • Conventional fractured reservoirs: overview and concepts
  • Conceptual integrated fault damage zone model
  • Value of outcrop analogs in fracture modeling
  • Conventional fractured reservoirs: facies, rock properties in core and well logs

Session 4

  • Conventional fractured reservoirs: rock properties from 3D seismic
  • Calibration of effective fracture permeabilities
  • Special considerations for flow simulation in fractured reservoirs
  • Putting it all together: Integration of outcrop, core, well logs, and seismic for improved reservoir models

Learning Outcomes

  • Highlight geologic concepts (e.g., mechanical stratigraphy, rock properties, faults, folds, etc.) that control natural fracture development in conventional and unconventional reservoirs
  • Demonstrate characterization methods that incorporate the use of 3D seismic data for improved mapping of mechanical facies and fracture properties (i.e., increased value of information)
  • Discuss workflows that combine geologic and geomechanics concepts, petrophysical properties, and seismic attributes within geological models in preparation for reservoir simulation
  • Discuss workflows that combine geologic and geomechanics concepts, petrophysical properties, and seismic attributes within geological models in preparation for reservoir simulation

Who Should Attend

This class is ideally suited for integrated teams working on characterization, modeling, and flow simulation of naturally fractured conventional and unconventional reservoirs: geologists, geophysicists, reservoir engineers, simulation engineers, and geomodelers.

Includes

Downloadable PDF course notes and spreadsheet-based exercises.

Instructor Biographies

Reinaldo Michelena
Chris Zahm
James R. Gilman