An organic geochemical study of the Miocene sedimentary sequence of Labuan Island, offshore western Sabah, East Malaysia


Author : Alsharef Albaghdady, Wan Hasiah Abdullah & Lee Chai PengPublication : Bulletin of the Geological Society of MalaysiaVolume : 46Page : 455-460Year : 2003


Description

Bulletin of the Geological Society of Malaysia, Volume 46, May 2003, pp. 455 - 460

 

An organic geochemical study of the Miocene sedimentary sequence of Labuan Island, offshore western Sabah, East Malaysia

ALSHAREF ALBAGHDADY, WAN HASIAH ABDULLAH AND LEE CHAI PENG

Department of Geology, University of Malaya, 50603 Kuala Lumpur

 

Abstract: Labuan is an island, located offshore west of Sabah, East Malaysia. The rocks on Labuan Island are divided into three main units; Temburong, Setap Shale and Belait formations. The relationship between these units is still unclear. An organic geochemical study was performed on ten samples from these main rock units. The main aim of this study was to determine the thermal maturity of these sediments and to differentiate between the formations based on organic geochemical parameters. The study suggests the thermal maturity is early mature to mid mature for oil generation, the Belait Formation being least mature and Temburong the most mature. Based on organic geochemical parameters and supported by vitrinite reflectance data, the Layang Layangan Unit I should be grouped within the Belait Formation.

 

Abstrak: Labuan adalah sebuah pulau yang terletak di luar pesisir pantai di bahagian barat negeri Sabah, Malaysia Timur. Batuan di Pulau Labuan dibahagikan kepada tiga unit utama: Formasi Temburong, Syal Setap dan Formasi Belait. Hubungan di antara unit-unit ini masih kurang jelas. Suatu kajian geokimia organik dilakukan ke atas sepuluh sampel dari unit-unit utama batuan ini. Tujuan utama kajian ini ialah untuk menentukan tahap kematangan terma sedimen-sedimen ini dan untuk membezakan di antara formasi-formasi ini berdasarkan parameter-parameter geokimia organik. Kajian ini mencadangkan kematangan terma adalah diperingkat awal ke pertengahan bagi penjanaan minyak di mana Formasi Belait yang paling kurang matang dan Temburong yang paling matang. Berdasarkan parameter-parameter geokimia organik dan disokong oleh data dari pantulan vitrinit, Unit I Layang Layangan sepatutnya diletakkan di dalam Formasi Belait.