DECISION MAKING IN PRIORITIZING HYDROCARBON PROSPECT TO DRILL AND DEVELOP IN INDONESIA PROLIFIC BASIN

• Main Author: Cessna Adyagharini, Aileron
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/62233
• Institution: Institut Teknologi Bandung

Indonesia has one of the oldest histories of the hydrocarbon industry, with the first commercial oil field discovery in Telaga Said, North Sumatera (Darwis, A. et al., 2007; Soeparjadi et al., 1975). Across Indonesia, out of 128 basins, 20 are producing basins (Chandra, 2020); within those 20 basins, some hydrocarbon discovery remains undeveloped, and prospect remains undrilled, especially prospects in deep-water setting and the Eastern Indonesia region. Hydrocarbon prospect is a potential hydrocarbon-bearing area in individual present-day trapping systems, holding economic value and exploitable with current technology and tools (Magoon and Dow, 1994; Otis and Schneidermann, 1997; Schlumberger, 2021). Choosing the “right” prospect to drill is essential to an oil and gas exploration and production company. Successful drilling will add new resources and reserves to the company portfolio and valuation. The deep-water Offshore Kutai Basin in Kalimantan still has many undeveloped discoveries and undrilled prospects, especially on the northern part of the basin. Determining a prospect to drill is sometimes constrained by technical issues, including surface and subsurface conditions, and not to mention other administrational limitations such as contracts and government regulation. The research will address the key aspects in the exploration and early development stage, selecting suitable criteria and sub-criteria in drilling decision-making, deciding the most critical criteria and sub-criteria, and concluding the most suitable prospect options to drill. The assessment will apply the decision-making method for the selection of the key aspects and criteria. The chosen decision-making method is Analytic Hierarchy Process (AHP). The development of the criteria and sub-criteria for the AHP model relies on Focus Group Discussion (FGD) and literature study. The selected AHP model concentrated on a comprehensive subsurface analysis, drilling strategy, and endorsement of proper contract type and reasonable timeline. The model generated three criteria and eight sub-criteria to select alternative hydrocarbon prospects to drill and develop. Three criteria used and applied to the hydrocarbon prospects prioritization are Geosciences, Drilling Plan, and Working Area. Sub-criteria under the Geosciences are Petroleum Geology, Resources, and Geological Risk Analysis. Second, Drilling Plan involves Well Objectives and Well Location sub-criteria. The last one, Working Area, comprises Contract Type, Contract Timeline, and Prospect Setting sub-criteria. The selection of the alternatives considers a cluster of mature prospects areas yet lacks oil and gas facilities, such as pipeline, production facilities, and storage facilities. The alternatives consist of prospect analog to a discovery published by Saller et al. (2008), deposited in the Miocene level as most of Kutai Basin exploration history, and situated on a block with only another six years left to operate. Next is the prospect analog to field published by Meciani and Orsi (2019), with stacks of multiple Pliocene reservoir targets and situated on a block with another twelve years of the contract. The AHP model utilized pairwise comparisons to establish relations within the structures and create a comparisons matrix under each criterion, creating the weighting ratio for the model. The prioritization calculation shows Geosciences as the highest criteria with 49.5%, followed by Drilling Plan (25.6%) and the Working Area (24.8%). Based on the global calculation, the top three results of the sub-criteria are Petroleum Geology of Geosciences with 21.53%, Well Objectives of Drilling Plan with 21.20%, and Resources of Geosciences with 15.10%. The three highest-ranking from the pairwise comparison applied to the prospect alternatives are Resources of Geosciences (80.5%), Well Objectives of Drilling (79.5%), and Contract Timeline of Working Area (73.0%), all three weighted on the field from Saller et al. (2008) prospect analog. The matrices multiplication between the global and prospect alternatives calculations also concluded that the Saller et al. (2008) prospect analog as the proposed prospect to drill with 61.20% of prioritization weight.