DEPOSITIONAL GEOMETRIES AND HYDROCARBON POTENTIAL WITHIN KUJUNG CARBONATES ALONG THE NORTH MADURA PLATFORM, AS REVEALED BY 3D AND 2D SEISMIC DATA

摘要

The back-arc basins of the East Java Sea are a continuation of the very prolific onshore basins. Exploration in the offshore areas, which began in the late 1960's has gone through three main cycles. The first two cycles resulted in only a few discoveries, mostly in the late 1980's, such as Pagerungan and West Kangean. The current exploration cycle has revitalised this largely under-explored area through several oil and gas discoveries. These include Bukit Tua, Jenggolo and Payang within the ConocoPhillips's Ketapang block, adjacent to the open Tanjung Lapak Blocks, small discoveries on the Karapan Block and in addition other discoveries such as Oyong, Ujung Pangkah and the onshore Banyu Urip. This paper is based on the interpretation of a 2729 km MC2D survey and 3963 sq km High Density MC3D (HDMC3D) survey acquired by PGS in 2002 and 2003 respectively. The HDMC3D survey is located over the North Madura Platform in the open North and Northeast Tanjung Lapak blocks, which are scheduled for offering in Indonesia's upcoming 4th Round. The high density nature of the 3D has enabled a detailed interpretation of the complex limestone reservoirs, whilst the regional nature of the 2D survey has allowed the identification of source rock kitchens, migration fairways, as well as the main tectonic events in the area. Interpretation of the seismic data has revealed numerous prospects and leads along the North Madura Platform within both Kujung Ⅰ and Ⅱ/Ⅲ carbonates. Some of these structures may have structural closures of greater than 100 km~2.