About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract

(Begin page 1183)

AAPG Bulletin, V. 85, No. 7 (July 2001), P. 1183-1210.

Copyright ©2001. The American Association of Petroleum Geologists. All rights reserved.

Integrating 3-D seismic data, field analogs, and mechanical models in the analysis of segmented normal faults in the Wytch Farm oil field, southern England, United Kingdom

Simon A. Kattenhorn, David D. Pollard

1Department of Geological Sciences, University of Idaho, Moscow, Idaho, 83844-3022; email: [email protected]
2Rock Fracture Project, Department of Geological and Environmental Sciences, Stanford University, Stanford, California, 94305; email: [email protected]

AUTHORS

Simon A. Kattenhorn received B.Sc. and M.Sc. degrees in geology from the University of Natal-Durban, South Africa, an M.S. degree in geology from the University of Akron, and a Ph.D. in geological and environmental sciences from Stanford University. He is currently an assistant professor of geological sciences at the University of Idaho. His research interests include applying principles of rock and fracture mechanics to fracture development, fault evolution, earthquakes, and planetary tectonics, using field mapping, numerical modeling, seismic reflection data, and seismological data.

David D. Pollard received a B.A. degree from Pomona College, a Ph.D. from Stanford University, and a D.I.C. from Imperial College, all in geology. He is a professor in the Department of Geological and Environmental Sciences at Stanford and is codirector of the Rock Fracture Project, an industrial affiliates program. His research interests focus on understanding rock fracturing and faulting using applications to fluid flow in heterogeneous reservoirs using outcrop and subsurface data, laboratory experiments, and numerical modeling.

ACKNOWLEDGMENTS

Three-dimensional seismic reflection data for this study were provided by BP Exploration Operating Company Limited and the Wytch Farm partnership companies: Arco British Ltd., Premier Oil Plc., ONEPM Ltd., Talisman North Sea Ltd., and Kerr-McGee Oil (UK) Plc. Interpretation software was provided to Stanford University and the University of Idaho by Schlumberger GeoQuest. Fault rendering used FAPS software provided by Badley Earth Sciences Ltd. Thanks to Richard Fox at BP for field assistance in southern England and to Giles Watts at BP for detailed information about Wytch Farm oil field. We thank Scott Young, Laurent Maerten, and Bashir Koledoye for technical support. Funding for this project was provided by BP Exploration Operating Company Limited and the Rock Fracture Project at Stanford University. Simon Kattenhorn acknowledges a McGee Grant Award from the School of Earth Sciences at Stanford University. We are grateful to Bruce Trudgill, Nancye Dawers, and Barry McBride for their constructive reviews of the manuscript.

ABSTRACT

We propose a methodology for the analysis of normal fault geometries in three-dimensional (3-D) seismic data sets to provide insights into the evolution of segmented normal fault systems and to improve recovery efforts in fault-controlled oil fields. Limited seismic resolution can obscure subtle fault characteristics such as segmentation and gaps in fault continuity that are significant for oil migration and thus accurate reservoir characterization. Detailed seismic data analyses that incorporate principles of normal fault mechanics, however, can reveal evidence of fault segmentation. We integrate seismic attribute analyses, outcrop analog observations, and numerical models of fault slip and displacement fields to augment the use of 3-D seismic data for fault interpretation. We applied these techniques to the Wytch Farm oil field in southern England, resulting in the recognition of significant lateral and, to a lesser extent, vertical segmentation of reservoir-scale faults. Slip maxima on fault surfaces indicate two unambiguous segment nucleation depths, controlled by the lithological heterogeneity of the faulted section. Faults initiated preferentially in brittle sandstone and limestone units. Subsequent growth and linkage of segments, predominantly in the lateral direction, resulted in composite fault surfaces that have long lateral dimensions and multiple slip maxima. Reservoir compartmentalization is greatest at the level of prevalent segment linkages, which corresponds at Wytch Farm with the predominant hydrocarbon-producing unit, the Sherwood Sandstone. At relatively shallower depths, fault segments are younger and less evolved, resulting in a greater degree of segmentation with intact relay zones.

(Begin page 1184)

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

AAPG Member?

Please login with your Member username and password.

Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].