IJOG 401 Indonesian Journal on Geoscience Vol. 8 No. 3 December 2021: 401-416 How to cite this article: Sabra, E., 2021. Evaluation of Hydrocarbon Source Rock Potential and Organic Geochemistry in North Arafura Shelf, Papua (Indonesia). Indonesian Journal on Geoscience, 8 (3), p.401-416. DOI: 10.17014/ijog.8.3.401-416 INDONESIAN JOURNAL ON GEOSCIENCE Geological Agency Ministry of Energy and Mineral Resources Journal homepage: hp://ijog.geologi.esdm.go.id ISSN 2355-9314, e-ISSN 2355-9306 Indexed by: SCOPUS (Q3) Evaluation of Hydrocarbon Source Rock Potential and Organic Geochemistry in North Arafura Shelf, Papua (Indonesia) Eriko Sabra Centre for Geological Survey, Geological Agency, Ministry of Energy and Mineral Resources Jln. Diponegoro 57, Bandung 40122, Indonesia Corresponding author: sabraeriko@gmail.com Manuscript received: May, 14, 2019; revised: January, 16, 2020; approved: January 26, 2021; available online: August, 22, 2021 Abstract - The results of this study identified two potential source rock intervals of Permian age in the North Arafura Shelf area of Papua, Indonesia. The first potential source rock interval (SR-1) was identified at 3834.9 m to 3838.6 m depth within the Kola-1 well, which is believed to be good to very good potential source rock with TOC in the range of 2.94 to 3.4 wt %, S1 0.78 to 0.97 mg HC/g, and S2 5.63 to 9.5 mg HC/g. The source rock is composed of type II and III kerogens with HI in the range of 164 to 275 mg HC/gTOC and reached the maturation stage with Ro of 0.83 - 0.86%, Tmax of 442 - 444 o C, and Production Index (PI) of 0.09 - 0.12. The second potential source rock interval (SR-2) is at 3060.1 - 3136.3 m depth in the ASM-1X well and has fair potential to be source rock with TOC of 0.95 wt %, S1 of 1.01 mg HC/g, and S2 of 3.39 mg HC/g. This source rock has type II kerogen with a HI value of 357 mg HC/g TOC and has reached maturation as indicated by a Ro value of 0.63%, Tmax of 430 o C, and PI of 0.23. Biomarker analysis revealed SR-1 is type III kerogen with terrigenous input and was deposited in an estuarine environment. Keywords: source rock, biomarker, Permian, eastern Indonesia © IJOG - 2021. Introduction Background The studied location is in eastern Indonesia, which is considered to be an exploration frontier for hydrocarbons. Several wells were drilled within the area (i.e. ASM-1X Wells, Kola-1, ASA-1, Buaya Besar-1, and South Oeta-1), but all are plugged and abandoned (Aldha and Ho, 2008) (Figure 1). However, poor documentation of source rocks in this area may lead to further unsuccessful exploration. Previous studies have been conducted regionally, in order to investigate the source rock potential (Peck and Soulhol, 1986; Sulaeman et al., 1990; Livsey et al., 1992; Kend- rick and Hill, 2002; Aldha and Ho, 2008; Subroto and Noeradi, 2008). Unfortunately, none of these studies have applied comprehensive source rock evaluation in smaller, more discreet areas. The present study intends to investigate the source rock potential based on the evaluation of quantity, quality, and maturity of organic matter within a specific area. In addition, several biomark- er parameters will be used to determine the source of hydrocarbons. The goal is that these results will provide guidance for future exploration endeavors.