About This Item
- Full TextFull Text(subscription required)
- Pay-Per-View PurchasePay-Per-View
Purchase Options Explain
Share This Item
The AAPG/Datapages Combined Publications Database
AAPG Bulletin
Abstract
AAPG Bulletin, V.
2007. The American Association of Petroleum Geologists. All rights reserved.
DOI:10.1306/03080706051
Methodology for risking fault
seal
capacity: Implications of fault zone architecture


Roald B. Farseth,1 Eivind Johnsen,2 Susanne Sperrevik3
1Hydro ASA, Research Centre, Box 7190, N-5020 Bergen, Norway; roald.farseth@hydro.com
2Eni Norge AS, Box 101 Forus, N-4064 Stavanger, Norway; eivind.johnsen@eninorge.com
3Statoil ASA, Box 7200, N-5020 Bergen, Norway; sperre@statoil.com
ABSTRACT
We introduce a methodology for quantifying the risk associated with a seal
for fault-bounded prospects. Applying this methodology, the aspects of fault
seal
are confined within four main risk categories. The methodology allows comparable criteria to be applied in the risking procedure to reduce uncertainty in fault
seal
assessments. As a foundation for the methodology, we combine onshore and offshore data from large faults and demonstrate
how
architecture and the distribution of fault rocks may influence sealing capacity. Despite the variable and complex structure of fault zones, we have observed fault zone characteristics that appear in common to the faults investigated, and we consider these factors to be crucial in the risking of fault
seal
predictions. The fault zones in our database, typically bounded by external slip surfaces, represent two main categories: (1) a layer of shale smear entrained into the fault zone and derived from a thick shale source layer within the sequence offset by the fault and (2) fault zones characterized by internal slip surfaces, slivers of footwall and hanging-wall–derived material rotated along the fault zone and commonly enclosed in a matrix of shaly-silty fault gouge. This study highlights the disparity between the complexity of actual faults and the abrasion-type shale gouge ratio (SGR) algorithm currently used in the industry to estimate sealing capacity of faults, which assumes that the seismically derived throw is concentrated in a single fault plane. We discuss
how
this may influence sequence juxtaposition across a fault, the associated SGR values, and ultimately, the fault
seal
risking.
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 members@aapg.org.