Organic geochemical,petrographic and palynological characterization of claystones of the Palaeogene Toraja Formation,and oil seeps in the Enrekang Sub-basin,south Sulawesi,Indonesia:Implications for hydrocarbon source rock potential  

作　　者：Agus Ardianto Budiman Komang Anggayana Agus Haris Widayat Dwiwahju Sasongko Rakhmat Fakhruddin 

机构地区：[1]Research Group of Earth Resources Exploration,Faculty of Mining and Petroleum Engineering,Institut Teknologi Bandung,Jln.Ganesha 10,Bandung,40132,Indonesia [2]Department of Mining Engineering,Faculty of Industrial Technology,Universitas Muslim Indonesia,Jl.Urip Sumohardjo Km 05,Makassar,Sulawesi Selatan,90231,Indonesia [3]Department of Chemical Engineering,Faculty of Industrial Technology,Institut Teknologi Bandung,Jln.Ganesha 10,Bandung,40132,Indonesia [4]Research Center for Geological Resources,National Research and Innovation Agency,Jl.Cisitu,Sangkuriang Bandung,Jawa Barat,40135,Indonesia

出　　处：《Energy Geoscience》2024年第3期117-134,共18页能源地球科学（英文）

基　　金：provided by Universitas Muslim Indonesia tothe first author(AAB).

摘　　要：An organic geochemical,petrographical,and palynological evaluation was conducted on 30 claystone outcrop samples of the Toraja Formation,along with a geochemical analysis of an oil seep in the Enrekang Sub-basin.The aim of the study was to determine the correlation between oil and source rock in terms of age,depositional environment,organic material sources,and maturity level.The total organic carbon content of the claystone samples varies from 0.03 to 4.52 wt%,which are classified as poor to excellent.The claystones are immature to post-mature with a mixture of TypeⅡandⅢkerogen.Their vitrinite reflectance values range from 0.47 to 4.52%Ro.The samples of Toraja Formation rock and the oil seep source rock might have a similar depositional environment,a deltaic marine depositional setting with high oxidizing conditions.Organic material sources for rock and oil samples are dominated by terrestrial input.The oil is inferred to have originated from the Paleogene source rocks,which correlates in age with the Toraja Formation.The recovered palynomorphs from the studied rock samples suggest a late Eocene to Oligocene age with a strong terrestrial influence of shallow marine depositional setting.The biomarker analysis shows that the rock samples have a more substantial contribution from the terrigenous higher plants,while the oil sample indicates a higher degree of marine influence.The maturity levels are also different between the oil(peak mature)and the analyzed rock samples(immature).It is inferred that the oil seep source rock is equivalent to the analyzed rock sample but more mature,having been deposited under more marine conditions.The oil seep source rock is not exposed and is located in the deeper part of the basin.A deeper marine facies(i.e.distal delta front and prodelta facies)in front of the distributary mouth bar within a delta is interpreted as the source rock of the oil seep sample.

关 键 词：Organic geochemistry PETROGRAPHY PALYNOLOGY Toraja Formation Enrekang Sub-basin 

分 类 号：P618.13[天文地球—矿床学]