ABSTRACT: Fault geometry and kinematics in the Peng Lai 19-3 Field, Bohai Bay, People's Republic of China
O'Reilly, J. Brendan1, Hongxing Ge2, Karl L.
Sharrah2, G. Thomas Morahan2, Mark C. Leach2, Qiangui Ma3
(1) Phillips Petroleum Company, Bartlesville, OK
(2) Phillips Petroleum Company (3) Chinese Offshore Oil Bohai Corporation, Tanggu, China
The Peng Lai 19-3 oil complex, located in the south-central Bohai Bay, People's Republic of China, was discovered by Phillips China Inc, in May 1999. The PL 19-3-1 discovery well encountered good quality fluvial reservoirs in the Miocene Pliocene Guantao and Minghuazhen formations with a gross hydrocarbon column of 425 meters. Ongoing appraisal drilling is confirming that a large accumulation of oil is present.
The PL19-3 field is a N-S trending anticline in the western flank of the central branch of the Tan-Lu wrench zone. The anticline is intersected by numerous NE-SW trending normal faults and by several N-S trending strike-slip faults. Systematic interpretation has resulted in a geometrically and kinematically consistent 3D structural model, which is consistent with the regional structures.
On the eastern flank of the anticline, high angle to vertical strike-slip faults are segmented or overlapping. Flower structures have formed where faults branch. Folds and pull-apart grabens have formed where the strike-slip faults step over or overlap. On the western flank of the anticline, basement wrench zones have formed short, en echelon faults in the overburden sequence.
The NE-SW trending normal faults divide the anticline into a series of horsts and grabens. Many faults terminate near the top of the Oligocene Dongying shale sequence. Others extend to the pre-Tertiary "basement". The bounding faults of the grabens display en echelon patterns, and there is a corresponding en echelon arrangement of the fold axes.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia