Abstract: Facies and Log Signatures of Sequence Boundaries in Sembakung Area, Tarakan Basin, East Kalimantan, Indonesia

P. Bambang, Muridno Hardjono, P. T. Silalahi Landong

Tarakan basin is one of the basins in East Kalimantan having a complicated geological condition. Tectonic repetition developed in this area constructed various stratigraphic traps. Sedimentary development in log data shows continuous regression in Meliat and Tabul Formations (Middle Meocene), Santul Formation (Late Miocene), Tarakan Formation (Pliocene) and Bunyu Formation (Pleistocene). Supported by seismic data, stratigraphic sequence in the basin is obvious, especally in Sembakung-Bangkudulis area. The sequence boundaries, mainly "lowstand" distribution as good prospective trap, can be mapped by applying tract systems and studying wavelet extract as seismic expression character of a reservoir. Subtle changes in pattern of stratigraphic sequences can become a hint of se imentary environment and its lithology content, supporting both exploration and exploitation planning.

AAPG Search and Discovery Article #90951©1996 AAPG International Conference and Exhibition, Caracas, Venezuela