Tectonic Evolution and Distributions of Triassic Sandstone at Bird Head Area: Implication of New Hydrocarbon Plays in West Papua, Indonesia

Abstract

Hydrocarbon exploration activity in the Eastern Indonesia has been very slow and stagnant for the last 10 years. New exploration play need to generate in order to attract new investor. Traditionally, Jurassic sandstone reservoir are the main exploration target which several giant oil and gas fields was discovered. Recent detail field geological mapping in the Bird Head of Papua Indonesia show the present of thick well-bedded quartz sandstone in the Gunung Botak area. Based on age determination using palynology analysis of samples collected from interbedded claystone within the sequence indicated early Jurassic to Late Triassic. Sandstone bed is characterized by well-bedded, reddish to pinkish color, medium grain quartz, sub-rounded to sub-angular, where petrography analysis indicated the occurrence of volcanic fragments. Total of volcanic fragment is decreasing toward the upper part of the section. Cross-bedding was observed in some sandstone with conglomerate interbedded in the lower part of the sequence. Based on field characteristic as well as petrography analysis, this sandstone sequence was interpreted as fluvial to deltaic deposit. Giant gas field was occurred within middle Jurassic sandstone in the Bintuni basin located to the south of Gunung Botak area. Triassic sequence was not present in this basin and was interpreted as being eroded or hiatus. New propose tectonic model and paleogeography was reconstructed using integrated surface and subsurface data including well and 2D seismic, zircon geochronology and balancing cross-section. Based on our new result, the distribution of Triassic sandstone is occurred between Bintuni basin and Gunung Botak area and it becomes a new exploration target area.

AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019