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A geochemical evaluation of the West Crocker Formation
- clues to deepwater source rock facies?
AzLINA ANuARl, PETER ABOLINS
1
, PAUL CREVELLo
2
AND WAN HASIAH ABDULLAH
3
1PETRONAS Research and Scientific Services Sdn. Bhd.
Lot 3288 & 3289, off Jalan Ayer ltam, Kawasan Institusi Bangi
43000 Kajang, Selangor Darul Ehsan, Malaysia
2Petrex Asia Sdn. Bhd.
7-15-2, Kirana, 7 Jalan Pi nang, 50450 Kuala Lumpur, Malaysia
3Department of Geology, University of Malaya
50603 Kuala Lumpur, Malaysia
Paper 6
Recent exploration activity in the present day deepwater areas of offshore northwest Sabah have resulted in
varied successes in the targetted turbidite sands; results ranging from dry wells to considerable oil discoveries. These
mixed results have raised some issues regarding the hydrocarbon charge in a turbidite setting, particularly
concerning the source rock distribution, quality and maturity (Walker, 1978).
Almost all published geochemical studies to date have focussed on the shallow water (present day and ancient)
areas of offshore Sabah and have discussed source facies dominated by dispersed terrigenous organic matter (Azlina
Anuar, 1994; Leong et al., 1999). However, are these source facies appropriate models for deepwater depositional
settings? To try to address this issue, a field study and subsequent geochemical characterisation study, of an onshore
deepwater analogue - the West Crocker Formation - were carried out. The West Crocker was selected by virtue
of geographic and temporal proximity to the current exploration turbidite targets. In this way, source facies
variations were minimised. Furthermore, the West Crocker has been well described sedimentologically, with
several turbidite elements recognised and described in the field (Crevello, 1998; Crevello, 2001).
Warta Geologi, Vol. 29, No.6, Nw-Dec 2003
Warta Geologi (Newsletter of the Geological Society of Malaysia), Vol. 29, No. 6, November-December 2003
Copyright © 2017 by Geological Society of Malaysia (GSM)