Offshore hydrocarbon potential of Indonesia

Offshore producing Tertiary sedimentary basins in Indonesia account for 34% of total daily production and some 12% of cumulative production of oil. The producing basins offshore are basically the geological continuation of onshore producing basins. Exploration plays are in variations of traditional sandstone reservoirs, with occasional prospects in limestone, structural traps and potential stratigraphic traps. Offshore exploration has taken place mainly in the shallower part of the shelf regions although regional reconnaissance seismic reflection information on deeper waters also exists. The offshore potential is governed by the following criteria: regional tectonic setting; water depth, which is important for subsequent development; and development of clastic reservoir rock with limestone plays whose potential is of increasing significance. The knowledge of development of volcanic reservoirs in this rocktype seems important. Knowledge of geological criteria forms an essential prerequisite. In regional perspective, the South China Sea area does not conform to the typical Indonesian offshore basin setting, although geologically the Natuna basins form an undivided part of the Indonesian geological system.