Randal L Billingsley1, Vello Kuuskraa2
(1) Advanced Resources International, Denver, CO
(2) Advanced Resources International, Arlington, VA
ABSTRACT: Integrating Surface, Subsurface and Seismic Data with Geomechanical Modeling to Predict Areas of Increased Permeability in Naturally Fractured Gas Reservoirs
Commercially producing natural gas from tight, naturally fractured reservoirs often depends upon the ability to preferentially drill areas of high fracture permeability. Yet techniques for projecting fracture trends away from established production remain rudimentary, often relying on simple offset drilling. Currently, a field based research program is being conducted by Advanced Resources, Barrett Resources, and Burlington Resources, supported by the Department of Energy (PRDA DE-RA26-99FT40191), to improve technology in this area. Geomechanical modeling is being used as the integration framework for the interpretation and extrapolation of fractured reservoir data in areas of fault influenced production.
A key component is a thorough understanding of the subtle structure of the field area, from wellbore to regional scale, to identify favorable locations, prospects and trends. Geomechanical modeling provides the analytic framework for incorporating the three dimensional fracture, faulting, folding and stress data in the field area and capturing the reservoir's deformation history. The model output is a geographically grounded areal projection of accumulated stress and strain necessary for prospect generation and risk management in a fractured terrane. Deformation patterns and stress fields around faults are modeled using geometries derived from depth converted seismic data and quality controlled by matching projected geometries of deformation features to observed structure, fracture and production patterns.
Initial use of this approach has been successful in explaining fracture dependent production variability in areas of the Piceance Basin (CO) and Green River Basin (WY). The current research program aims at demonstrating its applicability in more diverse settings in other basins.
AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado