Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

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 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 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 hydrocarbon potential in the area, Potential of Kuningan Area e.g. Lundin Banyumas and PERTAMI- NA that holds a concession in most of The Kuningan Area is envisaged as the onshore West and Central Java. part of the Northwest Java Basin More recently in the Citarum Block (eastern part of Bogor Zone) which to the west, at the time beings, represents the southern flanking slope Ranhill Oil Company (BPREC) is doing of the Basin (Fig. 1). The Kuningan drilling activity in the Jonggol Area, area is part of Tertiary back-arc basin and the conclusive result is in of Java, and it is mostly covered by progress after several drilling volcanic products of Quaternary age, problems, however there are reported however outcrops exposed amongst minor gas shows. The intensive these volcanic products indicates that exploration in the surrounding the area is basically underlain by Pertamina’s Area to the south through Tertiary sedimentary rocks. Gravity detail study upon reconstruction the data also indicated the value of basin development of the area, will Bouger anomaly reaches -25 mGals encourage the area to be taken as and is interpreted as deep new exploration area. sedimentary basin up to 3 Km (Fig. Stratigraphic development 2). Based on those studies, it is indicates every stratigraphic unit play believed that the Kuningan area has a significant role in build-up the good potential of the petroleum petroleum systems of the Kuningan prospectivity. area as proved in the NW Java Basin Exploration activities in the (located to the north of Kuningan surrounding Kuningan Area are very Area) (Figure 2); however the intensive, such as in the associated development of every unit is very graben systems of onshore West Java. influenced by tectonic development of To the east and southeast of the area, the basin as a whole. From this point some exploration wells have been of views, the petroleum prospectivity drilled by several operators to test of the Kuningan Area is remaining

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showing possibility for petroleum Reerink returned to his store, his prospects. dream shattered, but he must be remembered as the first true Exploration History explorationist in , with his 'seed money from Nederlandsche The first exploration wells in Handel Maatschappij, the predecessor Indonesia were drilled by an of Royal Dutch Shell. entrepreneur Jan Reerink, near Madja The second phase of exploration in Jan Reerink in 1871 made the first West Java began about 1910 in the drillings for oil in the East Indies (Fig Northwest Java basin. So far this deep 3). The oilseeps are connected with 5 basin has only been explored in its m thick lenses of ash tuff between northern, shallower parts. It has dark marly clay shales. The local yielded nine fields with a cumulative population still collects some oil from production of nearly 80 million barrels the seeps. This first attempt for of oil. No significant results were exploitation of the mineral oil by achieved during early campaigns, until drilling failed due to the unfavorable 1931, when the BPM began a large- facies and the complicated structure. scale shallow stratigraphic drilling Jan Reerink is a son of a rice program, employing the counterflush huller, Reerink kept a 'toko' or general coring method. Several shows store in Cirebon, on the north coast of provided the impetus for a deep Java. However he had a dream of rotary drilling program during 1938 to finding petroleum in the Madja area, 1942. It was during this phase that south of Cirebon. After obtaining the the first commercial oilfield was backing of 'Nederlandsche Handel discovered, at Randegan in 1939. Oil Maatschappij' he visited the United was also found at Rengasdengklok, States and Canada where he collected perhaps earlier, but this was not personnel and drilling equipment. He commercial. then returned to Cirebon where he Following World War II and the began drilling at the Cibodas location post-war turmoil, exploration was in December 1871. finally resumed in 1967 by He used a 'Pennsylvania' style rig, PERTAMINA. The first well, with a rope to run the drill bit. No Djatibarang-44, discovered a major casing was available, so total depth field in a very unusual reservoir, the was 125 feet only. Power was Jatibarang Volcanics, a complex supplied by that cheapest of mixture of tuffs, basalts, andesites generators-water buffaloes. He drilled and volcaniclastics which are difficult three more wells at Cibodas, and to interpret on logs. Fractured found sub-commercial oil in two of tuffaceous sands provide the principal them. Reerink returned to North reservoir, dated as Eocene-Oligocene. America and purchased steam Although the Jatibarang field has equipment to replace the buffalos. In produced 72 million barrels of the 1874 he began his second drilling onshore West Java total cumulative campaign with two steam-drilled wells production of around 80 million at Cibodas, and three more at Panais, barrels of oil, eight smaller Madja and Cipinang, which accumulations have been discovered. unfortunately were all unsuccessful. Reservoirs in the smaller fields consist Between 1870 and 1876 the largely of porous carbonate buildups Nederlandsche Handel Maatschappij of the Cibulakan. Oil generation is spent Fl. 225,000 and Reesink himself postulated to have been from the Fl. 50,000. As many 'wildccatters' Lower Cibulakan Formation Talang after him, Reerink wanted to continue Akar lacustrine shales and coals. but the company would not spend any more money. On July 31, 1876

126 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

METHOD AND DATA modified to incorporate new data and ideas. In the case of Kuningan areas, The first component of the interpretations were based on assessment process involved analysis published sparse seismic-reflection of the published geologic and data, and although those geophysical data to identify areas of interpretations could be used to hydrocarbon potential and to identify depositional and structural ascertain the areal and stratigraphic trends, they could not be used to extent of potential petroleum source identify individual prospects, just to rocks, reservoir rocks, and traps give an over view of possible presence within these areas. of hydrocarbon in the Kuningan areas. Published and proprietary reports and information were compiled to Regional Geology better understand the depositional and tectonic history of each province Physiographically, West Java can and assessment area, to identify the be divided into four major blocks areas of hydrocarbon potential, and to (van-Bemmelen 1949); better establish the petroleum . Coastal Plain of Batavia (Dataran geologic framework on which the Pantai ) plays would be defined. . Bogor Zone (Zona Bogor) The scope of this study of . Bandung Zone (Zona Bandung) Petroleum Potential of Kuningan Area . Southern Mountain Zone (Zona ranged from studies of the regional Pegunungan Selatan) geology and tectonics of an area to detailed existing exploration history. The study area is mainly situated Potential petroleum generative in the Bandung Zone, and some parts sources were identified through the in Bogor Zone and Quaternary use of published and proprietary Volcanics. Van-Bemmelen (1949) geochemical studies and proprietary suggested that Bandung Zone is an data from exploratory and inter-montane depressions extending development drilling. Hydrocarbon in elongate shape from Pelabuhan indications from exploratory and Ratu in the west through Cimandiri production wells were used along with Valley and ends in Segara Anakan to analyses of well data to identify the east with 20 - 40 km width. He potential petroleum source rocks and also considered that Bandung Zone to estimate source-rock properties. was centre of West Java Geantiklin Potential hydrocarbon reservoirs which latter on collapse due to the and possible migration pathways from uplifting and filled by young volcanic source to reservoir were identified products of Quaternary age. The primarily through the use of published products are mainly andesitic to exploratory well data and basaltic volcanic rocks. In the north of interpretations of seismic-reflection study area, the main Quaternary profiles. Reservoir-rock properties and volcanoes which are part of the the presence of trapping mechanisms Bandung Zone from west to east are; were appraised by using information G. Gede, G. Pangrango, G. Tangkuban from published well-log/report Perahu, G. Beser, and G. Cakra analysis and from analogous Buana. stratigraphic units in producing areas. Identification of potential areas Tectonic Setting was based primarily on existing The Indonesian archipelago was interpretation and subsurface formed as a result of the interaction mapping of proprietary seismic- of the three major plates; the Indo- reflection data. Where feasible and Australian Plate, Eurasian Plate, and appropriate, the interpretations were Pacific Plate. The Indo-Australian Plate

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subductes beneath the southern Bandung area, which is represent by margin of the Eurasian Plate since the Cicadas (CDS) locality (Sunardi, Early Cretaceous. In the Neogene the 1997). interaction of those three major Plates The notion of three volcanic formed the Sunda-Banda Arc activities is confirmed on the basis of extending from Sumatra, Java and the present data. Lesser Sunda Islands. However, the Though the first activity (Pliocene subduction-related magmatism along volcanics) may have started much the Sunda-Banda Arc has been active later than the oldest age found in the at least since the Eocene. frame of present study (Bellon et.al. There are two major periods of (1989). Since the Early Pleistocene magmatism recorded in this arc; the and Late Pleistocene volcanic Late Eocene - Early Miocene and the activities are different by means of Late Miocene - Pliocene or even to geochemical characteristics, instead of Quaternary. The Early volcanic the results on the determination of activity produced what is called in the radiometric ages, a chronological literature as “old andesite” exposed classification will be adopted extensively along south coast of elsewhere for chronostratigraphical Sumatra to Java Islands. This old classification in the Bandung area. andesite corresponds to what is called Correlation between changes in as Jampang Formation in the Bogor chemistry with time seems likely to be Basin Province in West Java by present in analytical data. Hereafter, Martodjojo (1984). The second we apply classification of the rocks magmatism activity produced a series following the K-Ar ages. These are of volcanic and pyroclastic rocks of the Pliocene Volcanics including one medium to high K calc-alcalic sample of ~1.7 Ma the Old composition and formed a belt known Quaternary Volcanics, the Early as Bandung Zone where young Pleistocene Volcanics and the Middle volcanoes are widespread as presence to Upper Pleistocene Volcanics. in the north of survey area. One of the tectonic phenomena K-Ar age determinations combine resulted from the plate interaction is together with the results from the Cretaceous subduction extending petrographical and geochemical from Java to the Java Sea and finally analysis (Sunardi, 1997) allow up to the Southeast Kalimantan. This clarifying the detail differentiation of Cretaceous subduction is the most the volcanic rocks specially to identify tectonic feature believed in most the tectonic setting of ancient volcanic geologist work in Indonesian Region sequences. This is done with the (Hamilton 1979, Katili 1981). This line correlation of particular geochemical (cretaceous subduction) is the basis in characteristics of modern volcanic dividing the Java and Java Sea into rocks with their specific tectonic two major provinces, they area West setting (Wilson, M.,1994). It seems and East Java (Martodjojo 2003). that there exist the temporal chemical The major structural element in variation of the volcanic rocks in the West Java is in NW-SE direction as Bandung area, which could be constrained from geological and classified into three different volcanic geophysical data. Suwijanto (1978) activity, the Pliocene (4.1 Ma to 2.8 interpreted the major NW-SE Ma), Early Pleistocene (1.1 Ma to 0.21 structural alignments in West Java Ma) and Late Pleistocene (0.16 Ma to based on Citra Landsat. Whereas 0.039 Ma) volcanic activities. Instead gravity data in West Java also show of these three stages of volcanic the major NW-SE contour lineaments activity, it can be also stated that the in the subsurface (Figure 2). Those Upper Pliocene (1.73 Ma) occurred in results are in agreement with the the Southern volcanic range of structural patterns derived from

128 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

Landsat imagery interpretation in the most north of West Java (Todd dan survey area and also from field of Pulunggono, 1971), and it is believed observation. that this structure are known as Martojojo (1984) divided West deepseated faults of old structure. Java into several tectonic provinces Sunda trend in N-S direction was based on the sedimentation formed in Paleogen (Eocene-Late characteristics as follows; Northern Oligocene, 53-32 ma). Extensional Basinal Area, Bogor Trough, Southern pattern of the fault movement can be Slope Regional Uplift and Banten correlated with the Eocene-Oligocene Block. Banten Block is the most rifting along old basement breaks of western part of the Java Island and N-NNE strike process for Sumatra lies close to Sumatra. Further division specifically for the Central Sumatera by Martodjojo (2003) divided the basin (Heidrick & Karsani, 1993) it Banten Block into Seribu Carbonate seems that these trends continue to Platform in the north, Rangkas Bitung develop in the west and north part of sedimentary sub basin, and bayah Java represented by faults that High in the south and to the west separates the Sunda and Arjuna there are low and high called Ujung basin. Kulon and Honje High as well as Deep-seated N-S trend controls Ujung Kulon and West Malingping the Paleogene basin formation in Java Low. Several highs and lows (basin forming tectonics). The onset characterize the Banten Province of sedimentation after Paleogene bounded by N-S to NW-SE growth basin forming was characterized by faults. Bayah and Honje High terrestrial to shallow marine constitute Tertiary structural Highs sediments represented by Bayah or comprising mainly of volcanoclastics Walat Formation. Outcrops of this of Miocene age, and the Honje High is formation is not exposed in the study interpreted to form in response to the area, but exposed about 50 km to the movement along the Sumatra strike- south part of the study area. slip faults forming graben systems in Gravity data of Bouger Anomaly of N-S direction as seen in Sunda Strait. the Java Island Block show that the Whereas, the Bayah High lying to the Kuningan Area has NW-SE south of Rangkas area comprises orientations, and also show the large anticline trending in E-W presence of low gravity values direction. reaching 0 mGals. Whereas Residual Regarding to global tectonic Gravity shows the area has low activity in Java, there are three anomaly up to -25 mGals. This structural trends, they are Meratus residual clearly indicated the presence (trending in NE-SW direction), Sunda of low areas amongst high areas or (trending in N-S direction) and, Java can be interpreted as basin pods. (trending in E-W direction) trends Model of density contrast of 0.25, (Pulunggono dan Martodjojo, 1986). 0.15, 0 and – 0.15 made up to 3 Km From this point of view, the Kuningan depth also supports the presence of area shows the Sunda and Java this sedimentary pods. trends. Sunda trend indicated by From those gravity data, it can be several strike slips that trends N-S, interpreted that the Kuningan Aea as where Java trend regards to the block faulting areas with highs and development of thrust faults and folds lows in which the lows reach 3 Km with E-W trends. and has the potential of the presence These N-S trend major faults was of petroleum systems. Geological first founded at the Sunda Basin by cross section also supports this seismic study in western part of West interpretation where the model shows Java offshore, further study shows the presence of thick sedimentary that these faults can be traced to the

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basin cross the Kuningan Area (Fig. it is occurred as clastic and carbonate 4). rocks, which is represents a syn-rift and block faulted tectonics during Stratigraphy Paleogene. The structure of the sedimentary rocks is NE-SW to N-S Martodjojo (1984) divided West directions, which is placed in an Java into three major sedimentary oblique position to the present E-W provinces on the basis of sedimentary stretching arc system. Eocene characteristics during Tertiary, as volcanic rocks are found in the follows; subsurface of North West Java Basin. . Continental Shelf Province It inclines to the south and strikes NE- (Mandala Paparan Kontinen) SW directions. Clastic sediments . Bogor Basin Province (Mandala were deposited during the Eocene in Cekungan Bogor) the North West Java Basin. During the . Banten Province (Mandala Banten) Oligo-Miocene an offshelf carbonate

platform was developed in the The study area is part of Bogor southern mountain area. During the sedimentary Province. This Early Miocene, a volcanic activity sedimentary province is characterized occurred in the present day southern by gravitational flow sediments mountain area. This was interpreted containing fragments mostly of from the existence of a thick pile igneous rocks and sediments such as consisting of alternation of volcano- andesites, basalts, tuffs, and sedimentary rocks in the area limestones. The study area is mostly (Jampang Formation, formerly also built by young and old volcanic known as the Old Andesite Formation products and is interpreted to overlie (van Bemmelen, 1948). In the North the igneous and sedimentary units West Java basin, a back-arc basin was below. developed in this age, which was filled Pannekoek 1946 (quoted from up by turbidite and debris flows from Martodjojo 1984) underlined the the volcanoes in the southern area. important of two morphological To the north, the volcaniclastic generations; those are Pre-Late sediments grade into normal shelf Miocene morphology and Resent sediments (the present-day NW Java morphology. The boundary between petroleum basin). these two morphology generations is During Middle to Late Miocene axis an unconformity. The first consists of of the volcanically active arc migrated Jampang and Saguling formations, toward the north. In contrast, a whilst the latter consists of Beser and carbonate offshelf platform is thought Bentang formations (Martodjojo to have been developed. The 1984). carbonaceous rock unconformably The stratigraphy of the area as overlies the older volcanic rocks. infer from Regional geological map of Stratigraphy of the study area is the Garut and Pameungpeuk based on regional mapping. It Quadrangle, Jawa (Alzwar et al. 1992) consists dominantly of intrusive and consists of undifferentiated old extrusive rocks of young and old volcanics (QTv), Tuffaceous breccia volcanic products, and also (Tpv) and Young volcanics (Qyc and approximately 15% of Tertiary Qyp), and several sedimentary and sedimentary rocks from Oligocene to carbonate rocks of Oligocene to Pliocene. In the literature, this old Pliocene. volcanic products is called as un-

differentiated old volcanics. The Local Stratigraphy difference between those two The oldest rock exposed in products is difficult to be judged in Kuningan Area is of Oligocene in age, the field but from the position to the

130 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

Young Volcanoes. The young volcanic ranging from few centimeters to products normally lie in the foot twenty centimeters occurred. (lower part) of Young Volcanoes; whilst the old volcanic products are Petroleun System normally lie to the south of it. a. Source Rock However, literature study indicates that on the top of high topography In North West Java Basin, there normally is occupied by tuff or are three (3) primary source rock andesitic intrusion which is inter- types such as lacustrine shales preted to be young volcanic products. (mainly oil-prone), fluvio-deltaic coals Further observation suggest that and shales (oil and gas prone and the so called undifferentiated old marine claystoneslbacterial gas). volcanics as inferred from regional Many authors stated that the Talang map can still be divided into old Akar Formation have the best source volcanic products and Jampang rock potential in the North West Java Formation. This separation is based Basin. Gordon (1985) reported that on the degree of alteration and the coal and carbonaceous shales of mineralization in the rocks in addition the Talang Akar Formation to be an to the rock deformation. The Jampang excellent source rocks for Formation is recognised by more hydrocarbons generated within the intense in alteration and minerali- offshore sub-basin area. It was zation and rock deformation forming indicated that the hydrocarbons fractures and faults but the boundary derivation from terrestrial plant between them is very blurred and material. The other possibility of the cannot be judged clearly. hydrocarbon source rock is syn-rift The young volcanic rocks are lacustrine black shales sediments of composed of andesitic to volcanic the Jatibarang Formation (Jatibarang breccia and tuff. Tuffs are normally and Tugu Barat Fields). Oil and gas occurred at the top of the mountains have produced commercially from forming steep topography. This is fractured volcanoclastics in the interpreted to be the products of Jatibarang Field. There is evident that young volcanoes of Quaternary age. some of oil is sourced from lacustrine. The rocks are hardly altered. The rock composition of the old b. Reservoir volcanic rocks of Old Quaternary and Several reservoirs have produced probably Middle Miocene are nearly oil and gas in the North Java Basin. the same with those of young volcanic The Jatibarang Formation is one of products except lithologically it is the reservoir units that oil and gas more compact and hard, and also in come from fractured vulcanoclastics. some location the andesite rocks were The other reservoir is extensively the altered into argillic, prophilitic and Baturaja Formation developed across silicification phases. the North West Java and South From the mineralisation point of Sumatra Basins. view the old volcanic have hardly This unit contains of shelf mineralization both in quartz veins or limestones, coral reefs and bank altered zone whereas the Jampang complex and have well to excellent Formation show mineralization. The hydrocarbon potential. Leaching of mineralization associated with quartz fresh water formed porosities and veins become the indication of permeability. The Upper Cibulakan Jampang Formation of Middle Miocene clastic is an important reservoir too, volcanic products. This can be seen in which forms the main oil in the Western Block where quartz veins Massive and Main sandstones. This associated with sulphide minerals member is a prolific reservoir with

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excellent hydrocarbon potential, which coinciding with periods of active is found in sufficient thickness. The tectonics and fault movement. porosity of this reservoir is approximately 30% with the e. Trap Styles permeability up to 500 mD. The Parigi Structural styles and trapping carbonates build-ups are another mechanisms are similar in all of the reservoir with good porosities within North West Java Basin. The main the North West Java Basin. structural features are anticlinal This reservoir is typically very domes and tilted fault block traps. porous and often contains large Due to the large amount of sands and amounts of gas. The Parigi Formation coarse clastics in the reservoir has the best reefal build-ups and sections,fault traps often establish porosity development of all Tertiary cross-fault sealing relationships. carbonates. The Upper Parigi is a Stratigraphic traps have been found widespread platform/bioherm unit, where sands unit on-lap and drape which varies in thickness up to 150 m basement highs. These traps have in offshore and 500 m in onshore. The typically been restricted to the Talang reservoir development in Parigi Akar interval, although stratigraphic carbonates arises through the pinch-outs of other reservoir units are presence of vugular, moldic and likely. The carbonate build-ups within intergranular porosity distributed the Baturaja, the Mid-Main Upper through the carbonates section. Cibulakan, and the Parigi Carbonates

also provide good traps. c. Seal

Sealing intervals in the North West RESUME AND DISCUSSION Java Basin are the Upper Talang Akar Northwest Java Petroleum shales, Middle Baturaja shales, Middle Prospect & Play Miocene mudstones of the Upper Cibulakan Formation, and Cisubuh The North West Java Basin shales. consists of several plays (Suyono et.al, 2005); they are Jatibarang Play, d. Migration Pathway Baturaja Play, Upper Cibulakan Play, and Parigi Play (Figure 5). The The pathways for hydrocarbon Jatibarang Play comprises of migration may occur laterally andlor volcanoclastic flows .and tuffs. Oil - vertically out of the source rock. and gas are produced from its Lateral migration takes place within fractured, with structure is an E-W strata units with good horizontal trending anticline and cut by N-S permeability. Vertical migration occurs trending normal faults. The Baturaja when the migration direction is Play is represented by carbonates perpendicular to bedding. Lateral platform/reef complex, which migration pathways are typically developed over palaeohighs. This established in beds that continuity of build-up is a type of trap for oil and permeable units. In the North West gas and combined with drape over Java, the major conduits for lateral basement highs. The main reservoirs migration are predominantly north consist of coral algal reef with south oriented of the Talang Akar secondary porosity is formed by Formation. Vertical migration is very leaching of water. The other Upper prevalent in this region, with most Cibulakan Play consists of sandstones areas showing propensity for multiple sourced from the north and deposited stacked reservoirs. Faults provide the as sand ridges in shelf environment main conduits for vertical migration with faulted anticlines and pinch-out with rapid transport of fluids of sand bodies. The sand reservoirs

132 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

are the primary producing horizons. Ascaria, N. A., Muksin, N., Hernadi, The Parigi Play is widespread platform D., Samodra, A., Busuno, P., bioherm unit and known to contain Puspita, D., Play Concept of Syn- large quantities of gas and offer the Rift and Post-Rift Sediments in the best opportunity for new reserves at Half Graben System, Northwest reasonable cost. The Parigi build-ups Java, Indonesia, Indonesian are well developed in both onshore Petroleum Association, Proceedings and offshore areas. The reservoir 27th Annual Convention. developed rise through vugular, Bellon, H.R. Soeria-Atmadja, R.C. moldic and intergranular porosity that Maury, E. Suparka and Y.S. distributed throughout the carbonates Yuwono, 1989, Chronology and interval. Petrology of back-arc volcanism in Java. In: B. Situmoran (eds.). CONCLUSIONS Proc. 6th Reg. Conf. Geology Mineral Hydrocarbon Res. 1. The Kuningan Area is part of Southeast Asia GEOSEA VI, Jakarta Bogor Trough which is part of 1987, IAGI, p.245-257 Tertiary back-arc basin Fletcher, G. L., Bay, K. W., 1975. experiencing block faulting during Geochemical Evaluation – N.W. Paleogene. Java Basin, Indonesian Petroleum 2. The Kuningan Area is mostly Association, Proceedings 4th Annual covered by Quaternary volcanic Convention Vol. 1, p. 211-241. rocks, but underneath is Gordon, T. L., 1985. Talang Akar approximately 3 km thick Coals–Ardjuna Subbasin Oil sedimentary rocks of Eocene up to Source, IPA Proceedings 14th Pliocene. Annual Convention Vol. 2, p. 91- 3. Gravity data also support the 120. presence of thick sedimentary Hamilton, W., 1979. Tectonics of the units in the Kuningan Area. Indonesian Region. U.S. Geol. 4. Based on this study it is predicted Survey Prof. Paper, pp. 1078. that the Kuningan Area has an Heidrick, Tom L. & Karsani, A, 1993, encouraging potential petroleum A Structural and Tectonic Model of system for hydrocarbon the Coastal Plains Block, Central prospectivity potential. Sumatra Basin, Indonesia, 5. More geological and geophysical Indonesian Petroleum Association data have to be conducted to Volume , Pages 285 - 317 (1993) understand basin evolution and Katili, J.A., (1980), Geotectonics of petroleum systems as well as play Indonesia : A modern view, concepts. Directorate General of Mines,

271pp. BIBLIOGRAHPHY Martodjojo, S., 1984, Evolusi Cekung-

an Bogor, ITB, Disertasi Doktor, Alzwar, M., Akbar, N. and Bachri, S., 238 p. (1992). Geological Map of the Martodjojo, S., 2003, Evolusi Cekung- Garut & Pameungpeuk Quadrangle, an Bogor, ITB Press, 238 p. Java. Geol. Res. Developm. Cent., Mazied, M., 2002. Application of Bandung, Indonesia. Sequence Stratigraphic Concepts Arpandi. D., Patmosukismo, S., 1975. and Depositional Models for The Cibulakan Formation as One of Reservoir Mapping: An Example the Most Prospective Stratigraphic from the Upper Cibulakan Units in the North-West Java Formation in the L and LL Fields, Basinal Area, IPA Proceedings 4th Offshore Northwest Java, IPA Annual Convention Vol. 1, p. 181- Proceedings 28th Annual 210. Convention Vol. 1, p. 597-607.

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Patmosukismo, S., Yahya, I., 1974. Suyono, Sahudi K, Prasetya, I, 2005, The Basement Configuration of the Exploration in West Java: Play North West Java Area, Indonesian concept in the past, present and Petroleum Association, Proceedings future, efforts to maintain reserves 3rd Annual Convention, p. 129-152. growth, IPA Proceeding, pp. 267- Reksalegora, S. W., Kusumanegara, 281. Y., Lowry, P., 1996. A Depositional Todd, D.F. and Pulunggono, 1971, Model for the "Main" Interval, The Sunda basinal areas, American Upper Cibulakan Formation: Its Association of Petroleum Geologists Implications for Reservoir Conference, Houston. Distribution and Prediction, ARII Van Bemmelen, R.W., 1949. The ONWJ, IPA Proceedings 25th Annual Geology of Indonesia. Government Convention Vol. 1, p.163-173. Printing Office, Den Haag, Vol I, IA Reminton, C. H., Pranyoto, U., 1985. and IB, 732 h. A Hydrocarbon Generation Analysis Wilson, M., 1994, Igneous in Northwest Java Basin Using Petrogenesis, A Global Tectonic Lopatin's Method”, IPA Proceedings Approach, Chapman and Hall, 466 14th Annual Convention Vol. 2, p. pp. 121-141. Soulisa, B., Sujanto, F. X., 1979, Hydrocarbon Occurrences in the Kandanghaur-Cemara Area, North West Java, IPA Proceedings 8th Annual Convention, p. 223-245. Sudarmono, Herbudiyanto, S., Abdat, T., 2003. The State of the Art Finding New Oil and Gas Reserves in an Old and Mature Area, Offshore Northwest Java Sea, IPA, Proceedings 29th Annual Convention Vol. 2. Sunardi, E. dan Kimura, J., 1997. Temporal chemical variations of the late Neogene volcanic rocks around the Bandung Basin, West Java, Indonesia: An inferred timetable resolving the evolutionary history of the upper mantle. Journal of Mineralogy Petrology and Economic Geology, 93, h.103-128. Sutan Assin, N. A. D., Tarunadjaja, A. N. S., 1972. Djatibarang, The Discovery and Development of a New Oilfield, IPA Proceedings 1st Annual Convention, p. 125-137. Suwijanto (1978), Hubungan antara kegempaan dengan kelurusan struktur pada citra landsat di dae- rah Jawa Barat. Suatu Tinjauan, Riset Geologi dan Pertambangan, Jilid 1 No. 2, Hal 1 – 8.

134 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

Figure 1. The KuninganArea is located approximately 183 km SE of Jakarta and 13 km south of Cirebon, at the most eastern part of West Java Province

Figure 2. Producing basin to the north, marked by the presence of many fields. 750 m contour lines overlay on 2’nd degree residual gravity and colored Boguer anomaly background

135 Bulletin of Scientific Contribution, Volume 9, Nomor 3, Desember 2011: 125-138

F

igure3.

JanReerink, 1871near thedrillings Madja in inmade first foroil EasttheI

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136 Stratigraphy review of Kuningan area in relation to the petroleum potential (Edy Sunardi)

Kuningan Area Kuningan

Geologic Cross Section across the across Section Geologic Cross Figure 4.

137 Bulletin of Scientific Contribution, Volume 9, Nomor 3, Desember 2011: 125-138

Figure 5. Generalized stratigraphy of Northwest Java Basin (Suyono et.al, 2005)

138