In this month's AAPG BULLETIN...

July 2008

E&P NOTES

Effect of Zechstein Supergroup (Z1 cycle) Werrahalit pods on prospectivity in the southern North Sea

John R. Underhill and Kirsten L. Hunter
Mapping of the Werraanhydrit Formation (Zechstein Supergroup) in the southern North Sea highlights the profound effect that large, isolated and hitherto poorly documented halite pods have in the assessment of gas prospects and existing fields in the basin.

GEOLOGIC NOTE

Terminology for structural discontinuities

Richard A. Schultz and Haakon Fossen
Strain localization structures such as fractures, stylolites, and deformation bands have important effects on reservoir performance but lack a consistent terminology. The classical terms are reviewed and assessed and a new comprehensive nomenclature presented for joints, faults, fractures, anticracks, shear zones, and deformation bands.

ARTICLES

An experimental evaluation of the curvature-strain relation in fault-related folds

David P. Keating and Mark P. Fischer
The assumption that curvature is a direct proxy for strain in folded rock layers is tested by analyzing scaled models. Only for steeply dipping basement faults is there a direct correlation between curvature and strain at all stages of fold development.

The Khazzan gas accumulation, a giant combination trap in the Cambrian Barik Sandstone Member, Sultanate of Oman: Implications for Cambrian petroleum systems and reservoirs

John A. Millson, Jamie G. Quin, Erdem Idiz, Peter Turner, and Ahmed Al-Harthy
Accumulation within the Khazzan tight gas accumulation, northern Oman, is associated with Cambrian Barik Sandstone Member reservoirs in a semiregional stratigraphic-structural trap. Its discovery and development, as well as current geologic understanding, are presented and discussed.

Characteristics of Pleistocene deep-water fan lobes and their application to an upper Miocene reservoir model, offshore East Kalimantan, Indonesia

Arthur Saller, Ken Werner, Fransiskus Sugiaman, Andre Cebastiant, Ron May, David Glenn, and Craig Barker
An upper Pleistocene basin-fl oor fan was characterized from seismic data to provide analogs for reservoir elements in deep-water fi elds planned for development including Gendalo gas fi eld, offshore East Kalimantan, Indonesia. The model is consistent with well test and pressure data from the reservoir.

Origin of coast-perpendicular extensional faults, western Gulf of Mexico: The relationship between an early-stage ridge and a late-stage fault

Ramón H. Treviño and Bruno C. Vendeville
Offshore Corpus Christi, Texas is a coast-parallel growth fault system with a coast-perpendicular shale ridge overlain by a younger normal fault. A model is proposed to explain the origin and development of these two structures that exhibit a seemingly anomalous trend.

About the BULLETIN

First published in 1917 as the Bulletin of the Southwestern Association of Petroleum Geologists--AAPG’s predecessor organization--in order to disseminate scientific material from annual meetings of the S.A.P.G., the AAPG Bulletin changed its name one year later when S.A.P.G. became AAPG.

The AAPG Bulletin has been delivering quality research to the scientific world ever since. The first issue contained papers written by the best-known geologists of the day, and included papers on such topics as South America, Europe, and general geologic problems of structure and sedimentation.

While the 21st-century AAPG Bulletin has undergone some changes since 1917, enlarging to 8 ½ x 11” size to incorporate more material and being published digitally as well as in print, it continues to adhere to the primary purpose of the organization, which is to advance the science of geology especially as it relates to petroleum, natural gas, other subsurface fluids, and mineral resources.

Delivered digitally or in print monthly to each AAPG Member as a part of membership dues, the AAPG Bulletin is one of the most respected, peer-reviewed technical journals in existence, with recent issues containing papers focused on such topics as the Middle East, channel detection, China, permeability, subseismic fault prediction, the U.S., and Africa.