Pamanukan Cilacap Fault Zone (PCFZ), which oriented in NW-SE (Sumatran Trend) has been interpreted to become barrier between Neogene deep water basins in western and central Java, Bogor Basin and North Serayu Basin, respectively. PCFZ also controlled the development of the intra-arc transtensional deep water basin, and the distribution of the volcanoclastic Halang Formation. The PCFZ has been interpreted to have translated the eastern extension of SW-NE pre-Tertiary subduction zone ±200 km to the southeast. These tectonics models suggest that the prolific hydrocarbon zone associated with Sundaland, originally developed to the east of the Northwest Java Basin (NWJB) has been translated to the southeast along the PCFZ. The PCFZ is interpreted as a regional fault which controlled the N-S transtensional pull-apart Paleogene basins in NWJB. The PCFZ is likely to be part of the dextral Malacca strike-slip fault which controlled the development of the Paleogene basins in Sumatra. This regional tectonic reconstruction can be a possible alternative model to explain the distribution of numerous hydrocarbon seep in the Neogene deep water North Serayu and Banyumas basins with enigmatic origin in petroleum system, differed with the adjacent Bogor Basin to the west which shows no hydrocarbon seeps.
Author : Cipi Armandita, Awang Harun Satyana, M. Ma’ruf Mukti, Indra Yuliandri