An assessment of paleodepositional environment and maturity of organic matter in sediments of the Setap Shale and Belait formations in West Sabah,East Malaysia by organic geochemical methods

作     者：Amer M. Burgan Che Aziz Ali 

作者机构：School of Environmental and Natural ResourcesDepartment of GeologyFaculty of Science and TechnologyUniversiti Kebangsaan Malaysia 

出 版 物：《Chinese Journal Of Geochemistry》 (中国地球化学学报)

年 卷 期：2010年第29卷第1期

页      面：42-52页

核心收录：

学科分类：070902[理学-地球化学] 0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 0708[理学-地球物理学] 

基　　金：University Kebangssan Malaysia 

主　　题：有机质成熟度 沉积古环境 黑色页岩 地球化学方法 沉积物 评估 马来西亚 贝雷 

摘      要：The black shale samples collected from two Neogene formations in the Klias Peninsula area,West Sabah,have been assessed and characterized in details by gas chromatography,gas chromatography-mass spectrometry and a variety of organic geochemical *** aims of this study are to describe the characteristics of organic matter of these sediments in terms of source/type of the organic matter,assess its thermal maturity and paleoenvironment of deposition,based primarily on biomarker *** results of both formations do not reveal significant differences within the rock *** gas chromatograms of the saturated hydrocarbon fractions of the Setap Shale and the Belait formations displayed monomodal n-alkane distributions and nearly identical regular sterane compositions with a predominance of C27 regular *** are consistent with open marine depositional environments dominated by marine biological *** related feature of these rock extracts is the presence of a high relative abundance of gammacerane,indicating anoxic marine hypersaline source depositional *** relatively high abundance of common land plant-derived biomarkers,such as bicadinanes and oleananes,is a clear indication of a major terrigenous input to the source of the extractable organic *** predominance of oleanane biomarkers in both formations is indicative of angiospermis input and Tertiary source *** high C29/C30 hopane ratios,moderate development of C33-C35 hopanes,high abundance of tricyclic terpanes and a slight predominance of C27 regular sterane over C28 and C29 steranes are characteristic features tending to suggest a significant marine influence on these source rocks,thereby suggesting a mixed source *** 22S/(22S+22R)C32 hopane ratio has reached equilibrium,and this is supported by the high maturity level as indicated by the 22S/22SC31-33 extended hopane ratios and 20S/(20S+20R)C29 regular steranes ratios.