ABSTRACT: Structural control on the late Miocene sequence development of the Aru Area, North Sumatra Basin, Indonesia

Yulihanto, Barlian , R&D Centre for Oil and Gas Technology "LEMIGAS," Jakarta Selatan, Indonesia

Combined structural and sequence stratigraphic analyses of the Late Miocene sediment of the Aru Area, North Sumatra Basin, Indonesia reveal that the Late Miocene sequence development was controlled by strike-slip inversion phase along the NE-SW trending Tanjungpura Fault Zone, which had been started since the late of the Middle Miocene time. This inversion phase was characterized by development of either transpressional and transtensional zones in the southwestern and northeastern part of the Aru Area to form Late Miocene basin configuration. The occurrence of the transpressional zone in the southwestern part of the basin which resulted in uplifting of the southern margin of the basin and Barisan Mountain provide large sediments supply for the basin and control the dimension and distribution of the sedimentary sequence during the period of sea level rise.

The Late Miocene sedimentary sequence in this area is bounded by type-1 sequence boundary and comprises of grain-flow to turbidite lowstand sediments in the lower part of the sequence and were deposited along the margin of the transpressional and transtensional zones, subsequently was followed by deposition of the transgressive shales, and an oblique progradational tide dominated deltaic sediment which was mainly developed in the tranpressional zone.

AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia