Journal of Petroleum Geology, Vol.16, No.3, pp. 265-284, 1993

©Copyright 2000 Scientific Press, Ltd.

OIL SOURCE ROCK POTENTIAL OF THE LACUSTRINE JURASSIC
SIM UUJU FORMATION, WEST KOREA BAYBASIN
Part II: Nature of the organic matter and hydrocarbon-generation history

M. S. Massoud(1), A. C. Scott(1), S. D. Killops(2), D. Mattey(2) and M. L. Keeley(3)

(1) Dept. of Geology, (2) Chemistry Department, Royal Holloway and Bedford New College, University of London, Egham, Surrey, TW20 OEX.

(3) Intera Information Technologies, Highlands Farm, Greys Road, Henley-on-Thames, Oxon. RC9 4PS.

Abstract

The offshore West Korea Bay (WKB) Basin is one of a series of NE-SW rift basins which formed in Korea and eastern China over thin continental crust during the Late Mesozoic and Early Cenozoic, and is characterised by a two-layered structure -- a Cenozoic basin is superposed on a pre-Tertiary basin. In Part I of this paper (Massoud et al., 1991), paraffinic oils recovered from Mesozoic and Tertiary sandstone intervals were found to have been generated from different source beds. Also, a probable thick (400-500 m) Jurassic source bed for the Mesozoic oil was geochemically identified in the basinal offshore area of the lacustrine Sim Uuju sequence penetrated by Well 606.