INTEGRATED POST MORTEM ANALYSIS IN EXPLORATION WELLS KKP BLOCK, WEST NATUNA BASIN, INDONESIA

• Main Author: FITRIS SUNDEWI (NIM: 22015033), ROSA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30684
• Institution: Institut Teknologi Bandung

<p align="justify">West Natuna Basin is one of the sedimentary basins located in western Indonesia. This basin has a large resource potential. KKP block is part of the basin that not proven yet to be commercial hydrocarbon accumulation, although directly adjacent to a producing oil and gas fields. Several eksploration wells have been drilled, without discovery at all within the block. Through this research is expected to known the cause of the lack of hydrocarbon accumulation at KKP Block. <br /> <br /> Petroleum system analysis is conducted in the order to evaluate the main factor causing accumulation does not exist. Analysis involved geochemistry data analysis for source rock evaluation, and estimate hydrocarbon volume of active source rock. Elektofacies analysis, reservoir property value and seal capacity are defined from log data. Cutting, SWC, and biostratigrafi data analysis are used to defined environmental deposition. Interpretation seismik section and depth structure maps are the basis to evaluate migration pathways. <br /> <br /> Based on the analysis, the source rock has sufficient TOC content, 0,5-1% TOC, and mostly is type III, source rock maturity is reached at a depth of 12136 ft and 14104 ft. Volume of hydrocarbons is 14,5x109-60,5x109 bbl, sufficient to expulsion from active source rock. Reservoir rock is sandstone, part of the Lower Gabus Formation, which has porosity ranging from 0,14 to 0,16, is poor-fair quality. Seal rock is part of the Lower Gabus Formation and Muda Formation, has ability to hold a hydrocarbon column of 2021 ft oil and 1048 ft gas. Hydrocarbon traps are faulted anticline and erotional truncated. Hydrocarbon migration patways mainly occurred through the fault. Based on the evaluation of petroleum system, hydrocarbon accumulation does not occur at the prospect of exploration wells due to poor integrity of the traps, that lead to leaking of hydrocarbons during the hydrocarbon migration process.<p align="justify">