ABSTRACT: Tectonostratigraphy of the East Indonesian blocks
Villeneuve, Michel1, J. J. Cornee1, J. P.
Rehault2, C. Honthaas2, W. Gunawan3, and Geobanda group4
(1) CNRS, Universite de Provence, Marseille, France
(2) Universite de Bretagne Occidentale, Brest, France
(3) GRDC, Bandung, Indonesia
(4) N/A, N/A
Apart from the Asiatic, Australian and Pacific margin, four microblocks have been distinguished within the East Indonesia area. These blocks named Banda, Lucipara, Banggai-Sula and Irian Jaya, display very different stratigraphic and tectonic evolution.
The Banda Block exhibits an Upper Triassic carbonate platform, followed by constant drowning until the Oligocene. Oligocene pelagic sediments suffered overthrusting by an ophiolitic nappe prior to Mio -Pliocene molassic type sedimentation.
The Lucipara Block is composed mainly of a metamorphic basement intruded by Early Miocene volcanic arc material and capped by molassic or deep clastic sediments.
The Banggai-Sula Block exhibits a Triassic metamorphic and volcanic basement capped with clastic and pelagic Mesozoic sediments. A Tertiary shallow marine carbonate platform was then deposited. Molassic clastic sedimentation occurred during the late Pliocene.
The Irian Jaya Block exhibits marine clastic sedimentation during Paleozoic and Mesozoic times and a shallow marine carbonate platform during the Cenozoic (until the late Miocene). Volcanic arc intrusions, interbedded with marine sediments, occurred in the late Miocene.
Tectonostratigraphic affinities suggest a northern Gondwana origin for the Banggai-Sula, Lucipara and Irian Jaya blocks but the Banda Block, which broke away during the Late Miocene consequent to the opening of the Banda basins, seems to be different, despite its Gondwanan affinity.
Lithostratigraphic and tectonic data from each of these blocks will be detailed.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia