Publications

The Arun Field, located in the North Sumatra Basin, Indonesia, is historically one of the largest and most significant natural gas fields in Southeast Asia. Its development has played a crucial role in Indonesia’s energy sector and economic growth. The Arun gas field was discovered in 1971 by Mobil Oil Indonesia (a subsidiary of ExxonMobil). It was one of the biggest gas discoveries in Indonesia at the time, with an estimated reserves of over 17 trillion cubic feet (Tcf) of natural gas. The discovery solidified North Sumatra Basin as a major hydrocarbon-producing region.

The geological and petrophysical complexities can make it challenging to fully understand and model the reservoir. Carbonate reservoirs, often exhibit significant spatial heterogeneity. Rock properties, such as porosity and permeability, can vary widely over short distances due to variations in depositional environments, diagenetic processes (such as cementation and dissolution), and structural features. The presence of fractures, vugs (large pore spaces), and karstification (where dissolution has created larger voids) further complicates the distribution of reservoir quality. These features create both high-permeability pathways and low-permeability zones, making fluid flow unpredictable. The degree of cementation can reduce permeability, while dissolution can create high permeability vugs, but these features are often unevenly distributed.

The aim of this study is to develop a reliable reservoir model to address the heterogeneity within the Miocene-aged carbonates and using the model for carbon capture, utilization, and storage (CCUS) initiatives.