Facies Analysis Based on Outcrops and Petrographic Study on Turbidite Deposits of the Cinambo-Halang Formation, Bogor Zone, West Java, Indonesia: Providing a Better Understanding of the Bouma Sequence

Abstract

The Bantarujeg area of West Java, Indonesia, is known for submarine fan turbidite deposit that forms the widespread Cinambo Formation. The Cinambo Formation is Late Oligocene–Early Miocene in age. Deposited conformably above it is the Gunung Kromong Limestone Complex. The Halang Formation is conformably deposited above the latter, and is subdivided into the Lower Halang Formation consisting of breccia, claystone, tuff, and conglomerate, and the Upper Halang Formation consisting of tuffaceous sandstone, claystone, and conglomerate. The Halang Formation is Middle Miocene– Late Miocene in age.

The turbidity current depositional mechanism in Majalengka is related to the morpho- tectonic settings during the early rifting in the Bogor Basin. The Oligocene extensional regime and subsequent normal block faulting in the Bogor Basin that caused a steep slope gradient from the neritic shelf margin marine in the northern Java coast to upper bathyal marine along the axis of the Bogor Basin. The Cinambo Formation and Halang Formation represent two sequences of sedimentary deposits related to sediment gravity flow. From the bottom to the top, grain size coarsens, due to progradation of a deep submarine fan. In detail, the internal characteristics of individual turbidites follow a Bouma sequence.

Based on field data observation and analysis can provide an overview of the fieldoutcrop perspective in relationship with reservoir and seal characteristics, rock distribution and properties from proximal to distal turbidite facies area. This overview can be applied in deepwater turbidite oil and gas fields, that are depending upon subsurface geophysical data.

AAPG Datapages/Search and Discovery Article #90196 © 2014 GCAGS, Lafayette, Louisiana, October 5-7, 2014