Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi) 125 STRATIGRAPHY REVIEW OF KUNINGAN AREA IN RELATION TO THE PETROLEUM POTENTIAL Edy Sunardi Lab. Sedimentology dan Geologi Kuarter, Fakultas Teknik Geologi, UNPAD ABSTRACT The West Java area is part of back arc basin comprising a number of North-South oriented half graben and sub-basin situated at the southernmost edge of the Sunda Platform. The area chosen for this study is called as Kuningan Area, located at the Bogor Trough, which has a complete sequence of rifting events. However, limited wells are available; therefore, a basin fill history could not be identified. It is predicted that this area has a hydrocarbon potential. Play concepts in the Northwest Java Basin, especially focused on syn-rift and post-rift sediments, whilst in the past they concentrated on carbonate build-ups on structural highs and the Jatibarang volcanics. In the offshore of NW Java Basin, to the north of this area, the proven oil and gas province are scattered in the several sub-basins such as Northwest Java Basin and Arjuna Basin. A number of different plays as shown in structural cross section in W-NE direction of the West Java Basin show the presence of extensive block faulting in the basement forming graben-like structures. The deposition of carbonate build-up is clearly indicated as Baturaja Formation in the lower part and Parigi Formation in the upper part. It is hoped that this configuration extends to the Kuningan Area which is mostly covered by thick Quaternary volcanic rocks. Key words: hydrocarbon potential, Northwest Java Basin.. INTRODUCTION General Interset of Petroleum Potential of Kuningan Area The Kuningan Area is envisaged as part of the Northwest Java Basin (eastern part of Bogor Zone) which represents the southern flanking slope of the Basin (Fig. 1). The Kuningan area is part of Tertiary back-arc basin of Java, and it is mostly covered by volcanic products of Quaternary age, however outcrops exposed amongst these volcanic products indicates that the area is basically underlain by Tertiary sedimentary rocks. Gravity data also indicated the value of Bouger anomaly reaches -25 mGals and is interpreted as deep sedimentary basin up to 3 Km (Fig. 2). Based on those studies, it is believed that the Kuningan area has good potential of the petroleum prospectivity. Exploration activities in the surrounding Kuningan Area are very intensive, such as in the associated graben systems of onshore West Java. To the east and southeast of the area, some exploration wells have been drilled by several operators to test hydrocarbon potential in the area, e.g. Lundin Banyumas and PERTAMI- NA that holds a concession in most of the onshore West and Central Java. More recently in the Citarum Block to the west, at the time beings, Ranhill Oil Company (BPREC) is doing drilling activity in the Jonggol Area, and the conclusive result is in progress after several drilling problems, however there are reported minor gas shows. The intensive exploration in the surrounding Pertamina’s Area to the south through detail study upon reconstruction the basin development of the area, will encourage the area to be taken as new exploration area. Stratigraphic development indicates every stratigraphic unit play a significant role in build-up the petroleum systems of the Kuningan area as proved in the NW Java Basin (located to the north of Kuningan Area) (Figure 2); however the development of every unit is very influenced by tectonic development of the basin as a whole. From this point of views, the petroleum prospectivity of the Kuningan Area is remaining