PETROLEUM SYSTEMS AND PLAYS OF BORNEO AND PALAWAN
Richard W. Murphy
Weybridge, Surrey, UK
Nine major petroleum systems in the eight significant basins of Borneo and Palawan contain 23-26 BBOE of discovered hydrocarbons. Plays may be viewed as those containing major fields (>50 MMBOE), minor fields (<50 MMBOE), plays that don’t work and frontier plays. They may be further subdivided by trap type, basin setting (delta sag or rift/sag), by reservoir (sandstone or carbonate) and by environment (shelfal or turbidite).
The nine petroleum systems are:
- Middle Miocene to Pliocene sandstone reservoirs in a variety of structural and structural-stratigraphic traps in the Sabah Basin.
- Upper Miocene to Pliocene deltaic sandstone reservoirs in shallow, faulted, four-way anticlines in the Tarakan Basin.
- Oil and gas in very large quantities in long, parallel, unfaulted north-south-trending anticlines in the Mahakam Delta. Reservoirs are west-east-trending channel sandstones.
- Oil and gas in deep water Makassar Sea outboard of the producing shelf with turbidite sands as the reservoir and associated ponded deep water marine shales as the source.
- Oil in upthrust anticlines in the Tanjung Raya area of the Barito Basin
- Oil and gas from Cycle II and III deltaic sandstone reservoirs in complexly faulted structures in the Balingian Province.
- Huge amounts of gas and minor amounts of oil from Cycles V and IV reefs and platform carbonates on the Luconia Shoals microcontinent.
- Large reserves of oil and gas from Cycle V and VI deltaic and turbidite reservoirs in the Baram and Champion deltas in a variety of complexly faulted structural traps.
- Oil and gas in reefs flanking a rift source basin on the North Palawan microcontinent.