The Frontier Halmahera Basin, Eastern Indonesia: A New Hydrocarbon Province?

Ryan, Marc C.; Butcher, H.; Halvorsen, T.; Kuilman, L. W.; Demichelis, J.; Sayentika, A.; Jansson, A.; van Koeverden, J. H.; Wall, M.; Messina, C.; Hay, S.; Kulsrud, G.
Statoil, Stavanger, Norway.

The Halmahera Basin is frontier acreage located within the Eastern Indonesia archipelago between Sulawesi and West Papua. The basin is covered by a loose speculative 2D seismic grid. No wells have been drilled in the basin.

Statoil (operator, 80%) and Niko Resources (20%) were awarded the 8,215 km2 Halmahera II PSC in the Halmahera Basin as part of the Indonesian 2011 Phase I Regular License Round offering. Firm commitments for the first three years of exploration include 6,000km of 2D seismic acquisition and geochemical study.

Given the frontier nature of the block, the petroleum system is yet to be proven. Nevertheless, a source analogue, the Miocene Klasafet Formation marine source rock, is proven to be working in the Salawati Basin, some 120km southeast of the block. Statoil and Niko aim to help de-risk the source rock presence and maturity prior to a decision to drill by undertaking a multi-beam survey with seabed coring and geochemical analysis of the samples as part of the firm work program.

Two reservoirs have been identified in the Halmahera Basin and included in the petroleum system:

1. Oligocene/Miocene Carbonate Reefal Buildup Play. Several carbonate growths on basement highs are thought to exist within the block. The 2D seismic acquisition work commitment (6000km) will help further mature the play and identify drillable prospects.

2. Re-deposited Carbonate. A large re-deposited carbonate sediment slope apron (3800km2) is mapped adjacent to a large long-lived Miocene to present carbonate platform margin. Two large anticlines lie well placed within this base of slope apron facies, trapping these sediments within four-way closures.

An additional Australian' Mesozoic play with high impact potential has been also been suggested to be present in the block, however, current seismic quality is insufficient to evaluate this play.

AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012