About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Special Volumes

Abstract

R. Sorkhabi and Y. Tsuji, 2005, Faults, fluid flow, and petroleum traps: AAPG Memoir 85, p. 153-180.

DOI:10.1306/1033722M853134

Copyright copy2005 by The American Association of Petroleum Geologists.

Distribution and Nature of Fault Architecture in a Layered Sandstone and Shale Sequence: An Example from the Moab Fault, Utah

N. C. Davatzes,1 A. Aydin2

1Department of Geological and Environmental Science, Stanford University, Stanford, California, U.S.A.; Present address: Earthquake Hazards Team, U.S. Geological Survey, Menlo Park, California, U.S.A.
2Department of Geological and Environmental Science, Stanford University, Stanford, California, U.S.A.

ACKNOWLEDGMENTS

We acknowledge the financial support of the Rock Fracture Project in the Geological and Environmental Science Department at Stanford University. Useful feedback and discussions were provided by Peter Eichhubl. We also thank Bill Dunne, Jonathan Caine, Rasoul Sorkhabi, and Jennifer Wilson for careful reviews of the manuscript, which helped us improve the clarity of the presentation.

ABSTRACT

We examined the distribution of fault rock and damage zone structures in sandstone and shale along the Moab fault, a basin-scale normal fault with nearly 1 km (0.62 mi) of throw, in southeast Utah. We find that fault rock and damage zone structures vary along strike and dip. Variations are related to changes in fault geometry, faulted slip, lithology, and the mechanism of faulting. In sandstone, we differentiated two structural assemblages: (1) deformation bands, zones of deformation bands, and polished slip surfaces and (2) joints, sheared joints, and breccia. These structural assemblages result from the deformation band-based mechanism and the joint-based mechanism, respectively. Along the Moab fault, where both types of structures are present, joint-based deformation is always younger. Where shale is juxtaposed against the fault, a third faulting mechanism, smearing of shale by ductile deformation and associated shale fault rocks, occurs. Based on the knowledge of these three mechanisms, we projected the distribution of their structural products in three dimensions along idealized fault surfaces and evaluated the potential effect on fluid and hydrocarbon flow. We contend that these mechanisms could be used to facilitate predictions of fault and damage zone structures and their permeability from limited data sets.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24