Abstract: Wrench Fault Control of Sedimentation in the East Java, Madura, Sakala and Bali Basins

Cynthia R. Coron

Superimposed over a series of Mesozoic fault-controlled, NE-SW trending arches and basins are younger E-W oriented, left-lateral wrench faults. These form part of a westward propagating system extending from the east Sunda Islands through west Java.

Activity along en echelon wrench segments and second-order, NW-SE crossfaults controlled the spatial/temporal distribution of Eocene through Pliocene lithofacies in the East Java, Madura, Sakala and Bali Basins. The location of early backarc thrusts may have initialized wrench movement as early as Middle to early Late Eocene, during which time the shelf/slope break from eastern Java to north of Kangean Island was coincident with the southern arm of the shear. Carbonate platforms and patch reefs developed on the upthrown sides of active faults onshore Java and east of Kangean Island during the Late Eocene, and in the Central Deep along reactivated faults of the pre-Tertiary trend during the Early Miocene. Several phases of transpression, accompanied by basin inversion and uplift, shape the topography of the Oligocene, Miocene and Pliocene seafloor, controlling the transitions from clastic to mixed to carbonate shelf environments and the shelf/slope break. Sporadic strike-slip movement along older faults translated mixed shelf/carbonate shelf-platform facies northward, adjacent to clastic facies of the Central Deep.

Continued transpression along the Sakala-Madura-Java wrench trend, concomitant with crustal shortening/collision in eastern Indonesia, resulted in the compressional folding and emergence of the Rembang Anticlinorium, and of Madura and Kangean Islands.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994