Maerten, Laurent¹, Frantz Maerten¹ 
(1) IGEOSS, Montpellier, France

ABSTRACT: Chronologic Modeling of Faulted and Fractured Reservoirs Using Geomechanically-Based Restoration

We present a new geomechanical tool that allows chronologic modeling of reservoir deformation. The method aims at restoring complex geological structures such as folded and faulted rock. It is based on the finite element method and simulates the physical behavior of rock mass and takes into consideration rock heterogeneous mechanical properties, fault mechanical interaction as well as tectonic stresses. 
To illustrate the method’s potential for evaluating faulted and fractured reservoirs, we analyze deformation and fault development, though time, in the hanging wall of a syn-sedimentary listric normal fault. As a case study example, we use one of the sandbox experiments carried out by McClay in 1990. A model of the final deformed stage of the analogue experiment was created and restored chronologically by removing the sedimentary layers one after the other. At each restoration stage, fault slip distributions are computed to facilitate the understanding of fault nucleation, propagation and sealing. The model is then analyzed in a forward sense so as to chronologically investigate fault development and deformation in the hanging wall of the basal listric fault. The numerical model corresponds well to the physical model and provides additional insights about the basin (reservoir) evolution and deformation. 
We conclude that the geomechanically-based 2-D and 3-D restoration of complex geological structures, has considerable potential for industry applications on fractured reservoir characterization and production. This method allows to characterizing, for key geologic and tectonic episodes, subseismic faults and fractures, reservoir compartmentalization, hydrocarbon migration pathways, and hydrocarbon traps.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.