--> Abstract: Hydrocarbon Potential of an Alkaline Lake Basin, by J. Y. Chen, G. Wang, and W. Ma; #91004 (1991)

Datapages, Inc.Print this page

Hydrocarbon Potential of an Alkaline Lake Basin

CHEN JIAN YU, and WANG GIJUN, China University of Geosciences, Wuhan, China, and MA WANYI, Research Institute of nanyang Oil Company, Nanyang, China

The Biyan basin is an oil-rich intermountain basin in the central part of China. It is a half graben with a marginal normal fault in the south and a slope in the north. The thickest Eogene reaches 7 km in the center of the depression. This basin became a typical alkaline lake with specific sedimentary sequences composed of oil shale, trona, dolomite, and dark mudstone during Early Tertiary because of dry climate and peripheral source areas rich in Na-containing minerals.

The source rock is characterized by abundant organic matter with a mean TOC of 2.5% and kerogen of good quality with H/C 1.4-1.7, and IH up to 800 mg/g. The study of biomarkers reveals a low Pr/Ph ratio and an abundant gammacerane and -carotane, thus indicating an environment of high salinity and reduction. All geochemical data demonstrate multiple provinces of primary organic matter, of which halophilous prokaryotic organisms are likely contributors. Crude oil in the Biyan oil field contains high wax and low sulfur. The low-mature oil is discovered in dolomite beds.

The high hydrocarbon potential of this basin is due to particularly favorable conditions for preservation and transformation of organic matter and high subsidence rates.

 

AAPG Search and Discovery Article #91004 © 1991 AAPG Annual Convention Dallas, Texas, April 7-10, 1991 (2009)