N. Makassar

Potential Source-Rocks

Non Atlantic-Type Divergent Margin

This Canvas autotrace of a seismic line of Makassar offshore illustrates the geological context of deep northern part of the Straits of Makassar. The generating petroleum sub-system of the Mahakam (continental domain) cannot explain the accumulations encountered in this deep offshore. The potential source-rocks are, quite likely, associated with the deep sediments of the non Atlantic-Type divergent margin (equivalent to a Mediterranean-type basin developed in association with a B-type subduction zone). The generating petroleum sub-system is, probably, dispersive in which the organic matter is transported from conventional offshore. Taking into account the geometry of the depocenters, the hydrocarbon migration is very convergent, which allows the formation of economic accumulations even if the source-rocks intervals are of poor quality.