ABSTRACT: Coalbed methane in Indonesia: an overlooked resource
Stevens, Scott H. , Advanced Resources International, Inc, Arlington, VA
The massive, low-rank coal deposits of Indonesia have not previously been targeted for coalbed methane (CBM) exploration and development. The prevailing view is that coal reservoirs in Indonesia are insufficiently mature to have developed high gas content and favorable permeability required for commercial development. Indonesia's coal basins are geologically unlike the five U.S. coal basins where CBM production has been successfully established.
However, a systematic evaluation of Indonesian coal basins based on well and seismic data indicates that the CBM potential in Indonesia may be considerable. Published accounts of Indonesian coals focus on surface outcrop and strip mines, where thick Oligocene and Miocene-Pliocene coal beds are of low sub-bituminous rank. But CBM exploration will target coal reservoirs at 500 to 1,500 m depth, where coal rank and gas content are much higher.
Recent CBM development in the U.S. has focussed increasingly on lower rank settings, such as the Powder River and Uinta basins. The Powder River basin of Wyoming--the world's most active CBM development with 1,000 new wells drilled in 1999--most closely resembles Indonesian coal settings. However, Indonesian coals are deeper and higher in rank compared with the Powder River basin and could be more productive. CBM basins with multi-Tcf potential include the Barito, Berau, Kutei, Tarakan, and North and Central Sumatra basins. CBM development costs will be high and projects may require special fiscal terms, which fostered CBM development in the U.S. ten years ago.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia