Regional Geology of Palawan 1

Regional Geology of PalawanResearch Paper

Jiann C. CapiralBachelor of Science in Petroleum Engineering

31 January 2015

Regional Geology of Palawan 2

Table of Contents

A.General Geology 4

B.Geologic History 6

C.Sedimentary Basins 9

1.Northwest Palawan 10

2. Reed Bank 11

3. Southwest Palawan 11

4. East Palawan 12

5. Mindoro-Cuyo Platform 12

D.Citations 13

Regional Geology of Palawan 3

Regional Geology of Palawan 4

A. General Geology of Palawan1.The Northern Palawan

Northern Palawan is constituted predominantly by Upper Paleozoic to lower Mesozoic sediments regionally metamorphosed and deformed mainly during Early Jurassic. This sequence was later intruded by intermediate plutonic rock (Kapoas granite) and subsequence overlain by relatively undeformed Upper Eocene to Recent sediments offshore. The northern parts of the main Palawan Island and the Calamian Group are composed of uplifted basement chert and limestone, which constitute in part.

The igneous bodies in the Northern Part are the Kapoas Diorite intruded at the Kapoas Peninsula and at east side of the Ulugan bay during the Oligocene time and the Manguao Volcanics exposed at the eastern side of the northern main Palawan Island in the Pleistocene time.

In the northern central part of the main Palawan Island , the basement consists of phyllitic rocks and mica schist. These basement rocks are covered by Tertiary Sedimentary rocks and thrusted over by the ultramafic rocks at Paly Island offshore east of the main Palawan Island.

The Northern Part is divided geologically into the northeastern zone and southwestern zone by the thrust which passes from the Kapoas Peninsula in the west side to the Calauag Bay in the east side.

a.) The Northeastern Zone

Outcrops of Guinlo Formation, which has been dated as Cretaceous were in the Busuanga Island and at the western side of the Calauag Bay in the northern part of Palawan Island.This formation, which unconformably overlies the Busuanga Formation, consists of massive quartzose sandstones with occurrences of mudstone and conglomerates.

The Bacuit Formation, which is exposed at the vicinity of El Nido is dated as Middle Permian in age by the studies of fossils found in some chert samples. (Fontaine, 1981, Wolfart et al., 1984.) b.)The Southwestern Zone

The Caramay Schist and the Concepcion Phyllite forming the basement rocks in this zone are thrusted over the Panas Formation and Busuanga Formation at the western and northern sides respectively. The Caramay Schist and the Concepcion Phyllite cover almost the entire area. The Concepcion Phyllite which is derived from alternating sandstone and mudstone is mainly distributed throughout the southwestern portion of the Northern Part thrusted over the cherty sediments at the northeastern portion and the Panas Formation at the northwestern side.

The metamorphic rocks have been considered to be Carboniferous to Permian in age by MGB (1981), but it was pointed out recently that these metamorphic rocks could probably be derived from some Cretaceous or Paleogene turbidite formations (R. A. Santos, 1988, oral.).

The Caramay Schist consists of muscovite, schist, quartz mica schist and graphite schist and is also characterized by an almost mica free quartzite.

The Concepcion Phyllite consists of phyllite mudstone, siltstone, sandstone and met-sediment, and is also associated with conglomerate mudstone.The Panas Formation is distributed along a narrow area from the eastern part of the

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Ulugan Bay to the eastern portion of Pandanan Bay.The Concepcion is thrusted over this formation.

This formation, which is assumed to be of Eocene age is inferred to have been a submarine fan deposit. It is composed of tightly folded, faulted and imbricated units of quartzo-feldspathic sandstone, mudstone and shale.

St. Paul’s Limestone is observed at the east side of Mt. St. Paul Bay with a northeast trend consisting of massive dark gray limestone and contains abundant algae, coralline detritus and foraminifera fossils which were dated as Late Oligocene to Middle Miocene age (BMG, 1981; UNDP, 1985). The Igneous Activities The Northern Part Only three igneous bodies are known to occur in the Northern Part, namely, the Kapoas Intrusives, the Mangunao Volcanics and the Ultramafics of Paly island. The Kapoas Intrusives are observed as several stocks trending NNE the east from the east side of El Nido through the Kapoas Peninsula to the east side of the Ulugan Bay in the vicinity of Stripe Peak. These stocks are dated Late Eocene to Early Oligocene by KAr method (UNDP, 1984; MMAJ, 1987). The Mangua Volcanics are observed as volcanic flows at the southern part of Manguao Lake in the northeastern main Palawan Island. The Ultramafics are observed at Paly Island which is located offshore at the northeast of the Northern part. These ultramafics are believed to be thrusted over the north Palawan block and contain chromite dissemination. 2.         The Southern Palawan                                   The igneous rock in the Southern Part is composed of basalt extrusives, thrusted ultramafics and the associated gabbros on both rock units. Dikes of pyroxynite and gabbro are widespread throughout the abovementioned rock units.          The Espina Basalt which is believed to be part of the basement and is of Cretaceous are is exposed as a window like-inlier in an area north of Puerto Princesa and in many localities with in Central and South Palawan areas.          The Mt. Beaufort Ultramafics are mainly made-up of harzburgite with irregular patches and lenses of dunites. Chrome spinel/chromites are known to exist and to occur as disseminations in these rocks./ These ultramafics are presumed to be of Eocene age.          The Stavely Range Gabbro along with the Mt. Beaufort Ultramafics constitute the Palawan Ophiolite which is thrusted over the Early Oligocene Pandian Formation and the Eocene Panas Formation. The thrusting is inferred to have occurred throughout the Eocene to Middle Miocene, although the inception of this activity is thought to have started during the Paleocene. The Basement Complex The basement complex of the Southern Part consists of the Sulu Sea Mine Formation, the Tagboros Formation and the Espina Basalt. The Sulu Sea Mine Formation consists of chert, mudstone and conglomerate and the Tagboros Formation is composed of green siltstone with wacke and conglomerate. Aside from being exposed as window

Regional Geology of Palawan 6

like-inliers at a small spot north of Puerto Princesa, these basement rocks are distributed east of Quezon, around the southwester portion of the mountain range of this part and in the Balabac Island.                                               These basement units are dated as Cretaceous in age.                        Tertiary Formation The Panas Formation is a turbidite formation which is composed of shale, mudstone and alternating arkose sandstone and is distributed at the west side of the Ulugan Bay, the periphery of the Pulot area and at the southwestern part of this area. The Panas Formation is associated with and partially alternates with the Sumbiling Limestone which is though to be a contemporaneous heteropic facies of the Panas Formation. The Pandian Formation is basically made-up of arkose sandstone associated with shale and siltstone, and considered to be Lower Oligocene in age. It is distributed at the west coast of the southwestern side of Quezon, overlying the Panas Formation unconformably. The Ransang Limestone composed of sandy and silty limestone is estimated to be Early Miocene age. It has a limited distribution at the eastern side of Quezon and at the eastern and northeastern portion of Rio Tuba. The Isgod Formation is composed of alternating sandstone, mudstone and siltstone is associated with coralline limestone. It is distributed at the east and southern sides of Quezon and is dated to be to Middle Miocene in age. The Alfonso XIII Formation consists basically of reefal limestone and overlies the Isgod Formation. This formation is distributed around the Aboabo area in the south and is found to be Late Miocene in age. The Sayab Formation consisting of alternating sandstone and shale beds and is exposed at the southwester part of Rio Tuba. It is to be late Miocene in age. Similar to the Alfonso XIII Formation. The Clarendon Formation consists of alternating sandstone to shale and is distributed at the southern part of Balabac Island and is found to be Pliocene in age. The Iwahig Formation which is composed of conglomerate and limestone bodies is distributed from Puerto Princesa to Narra in southeastern coast and at the vicinity of Wangle in the southernmost portion of the main Palawan Island. It is found to be Pleistocene in age as based on paleontological studies.

B. Geologic History

Palawan can be subdivided into two distinct terranes representing north Palawan and central and south Palawan.The

north-south trending Ulugan fault has been considered longtime as boundary. However, according to Letouzey et al.(1988), this boundary lies further to the north. The main difference is the continental character of north Palawan where the series consists of upper Paleozoic to lower Mesozoic rocks. They are part of the Chinese continental margin drifted from mainland China during late Oligocene to early middle Miocene time (Taylor and Hayes, 1983; Holloway, 1982).

Regional Geology of Palawan 7

Detailed studies of north Palawan have been published by Hashimoto and Sato (1973) and Fontaine (1979). Some additional

results were given more recently by Wolfart et al. (1986). Results from offshore northwest Palawan were presented by Salvidar-Sali et al. (1981) and Kudrass et al. (1986).

Mesozoic

South of Ulugan Bay large parts of Palawan and Balabac Islands are built up by the ophiolitic complex of oceanic crust.

It is composed of peridotites, gabbros, metagabbros, amphibolites, pillow basalts and greenshists. In the southern part of the Ulugan Bay, Segama Point (Fig. 3) pillow basalts and their overlying radiolarites are exposed. Peridotites are cropping out as large masses at the northern end of the Ulugan Bay (Mount Bloomfield) along the coast southwest of the bay and in central and southeastern Palawan. They were encountered in the wells offshore northeast Palawan, and they are also exposed on Paly Island east of north Palawan. That means that the accretionary wedge extends further to the northeast into the northwest Sulu Sea Basin, and that it is not bounded by the Ulugan strike slip fault (Letouzey et al., 1988). Small imbricated slices of ophiolites and pillow basalt were found south of St. Paul's Bay and Ulugan Bay as well as in the region southwest of Quezon City (south Palawan) and on Balabac Island. Calcareous red clay associated with pillow lavas in south Palawan west of Brookspoint and from Balabac Island yielded common poorly preserved nannoplankton. Only resistant species of the genus Watznaueria were preserved that has a very long stratigraphic range. However, the absence of

resistant late Cretaceous forms as well as the abundance of Watznaueria make an early Cretaceous age most likely. The same age was obtained by radiolarians from Sabah (Leong, 1977; Jasin et al., 1985; Rangin et al., 1990), where radiolarites associated with ophiolites occur in the same tectonic context. These ophiolites were imbricated most probably during middle Eocene time linked with the change in motion of the Pacific Plate at about 44-42 Ma (Letouzey et al., 1988). This is confirmed by the 40 m.y. K/Ar ages of the tectometamorphic parts of the ophiolites (Raschka et al., 1985).

A thick clastic series of turbidites with few conglomerates and intercalated red tuffaceous layers is widely exposed in central and northern Palawan. They are typical slope deposits with numerous slumps, debris flows, and dissociated sandstone layers. At the Underground River a middle-late Jurassic limestone block was found within this series (H. Fontaine, pers. comm., 1982). Plant fragments are common in several layers. The sediments are locally sightly metamorphosed, especially in the area of Barton and Roxas (Fig. 3). This series was dated at Ulugan Bay and in the Aborlan River (central Palawan) by nannofossils as the late Campanian-early Maestrichtian Quadratum trifidum Zone (Letouzey et al., 1988). The same age was obtained by Wolfart et al. (1986) from the area at Carugay near St. Paul's Bay (Fig. 3). Nannoplankton are rare and restricted to some layers. The assemblages consist of the following species: Quadratum trifidum, Ceratolithoides acutus, Watznaueria barnesae, Micula staurophora, Broinsonia pare a, Cribrosphaerella ehrenbergii, Ar/changeIskiella cymbiformis, and Eiffellithus turriseijfeli. A late Cretaceous age was also obtained using palynomorphs from offshore wells east off north Palawan. This sequence is known from central and northern Palawan but not from the south

Tertiary

Paleogene deposits are present from south and central Palawan, Balabac Island, and can be followed to north Borneo (Sabah). They are represented by the strongly folded "Crocker formation" dated by nannoplankton as late Paleocene to late Oligocene in age. Previous age determinations were based mainly on arenaceous foraminifers or on larger foraminifers from included limestone lenses which, however, do not allow precise datings. It seems that the lower Paleocene and part of the middle Eocene are represented by hiatuses , but it is difficult to confirm this assumption using the rare data obtained from the entire sequence. No middle

Regional Geology of Palawan 8

Eocene was determined with exception of the uppermost part (Zone NP 17). Most of these slope deposits are barren of nannoplankton probably due to the high input of detrital material. They consist of clay- and siltstone with bedded or massive slumps of quartz sandstone. Typical turbiditefeatures are common. Plant fragments are more or less frequent throughout the sequence. The upper Paleocene (nannoplankton Zones NP8 and NP9) has been determined in only one sample taken southwest of Quezon City (south Palawan) including following species: Sphenolithus anarrhopus, Fasciculithus tympaniformis, Toweius craticulus, Coccolithus cavus, Ericsonia subpertusa, Cyclococcolithus robustus, and Chiasmolithus bidens. Sediments of the same age were dredged from the Dangerous Grounds by Kudrass et al. (1986). The abundance of nannoplankton indicates deposition of these sediments in an open marine outer shelf to slope environment. Reworked nannoplankton species of Zone NP9 were found in middle to late Eocene sediments. Other samples taken in the area southwestof Quezon City yielded either poor assemblages of the lower Eocene (Zone NP12) with Marthasterites tribrachiatus, Discoasteroides kuepperi, and Discoaster barbadiensis, or of the upper middle Eocene (Zone NP 17) characterized by the occurrence of Sphenolithus obtusus, Sphenolithus moriformis, Cyclococcolithus formosus, Coccolithus eopelagicus,Reticulofenestra umbilica, Sphenolithus radians, Cribrocentrum reticulatum, Discoaster barbadiensis, Discoaster tani nodifer, and Discoaster saipanensis. These species occur generally together with reworked nannoplankton from the upper Cretaceous, upper Paleocene to lower Eocene (uplift and erosion after the middle Eocene tectonic event).The upper Eocene (Zone NP 18) was recognized in one sample including the same assemblage plus Chiasmolithus oamaruensis and Coronolithus germanicus. Middle to late Oligocene sediments (Zones NP24-NP25) were not found in Palawan with exception of the St. Paul limestone occurring as slices within the accretionary prism. These limestones are part of the large carbonate platform encountered in wells offshore northwest Palawan (Nido limestone) and dredged from the Dangerous Grounds (Kudrass et al., 1986). This platform plunges southward below the allochthonous wedge (Hinz and Schluter, 1983; Fricaud, 1984). Few pebbles of late Oligocene marls (NP24-NP25) are included in the lower Miocene sandstone exposed along the southwest coast of south Palawan. Those pebbles were alsoobserved in west Balabac (Taripit Point) where they occur in shelfal limestones rich in larger foraminifers (Lepidocyclines).These hemipelagic Oligocene sediments are rich in nanno-plankton with following assemblages: Dictyococcites dictyodus,Sphenolithus ciperoensis, Cyclicargolithus abisectus, Cyclicargolithus floridanus, Discoaster deflandrei, and Coccolithuspelagicus. Middle to late Oligocene red marls, including common displaced larger foraminifers, were also observed in a slump at Martinez Point (Balabac Island).

Neogene

The Neogene is well known from offshore wells. Onshore it is exposed only in south Palawan and Balabac Island, whereas it is unknown from onshore central and north Palawan indicating the strong uplift of the region since at least middle Miocene time (Fricaud, 1984). Calcareous quartz sandstone exposed along the west coast of south Palawan are probably of early Miocene age. Locally they contain microconglomerates alternating with siltstone sometimes rich in plant fragments. Occasionally displaced larger foraminifers are present. Early middle Miocene tuffaceous marl with some boulders of andesite is exposed along the Aboabo Quezon road. It contains the typical assemblage of Zone NN5 with: Cyclicargolithus abisectus, Cyclicargolithus floridans, Sphenolithusabies, Sphenolithus heteromorphus, Helicosphaera carteri, Discolithina japonica, Discoaster deflandrei, and Reticulofenestrapseudoumbilica. These sediments are part of the Cagayan volcanic arc series thrusted onto the accretionary wedge. A hiatus in south Palawan representing a part of the middle and upper Miocene might be related to the second tectonic event within the upper Miocene (uppermost part of Zone NN9 to Zone NN10), which is also recognized on seismic profiles (Fricaud, 1984). This event is well dated in other parts of the Philippines (Muller and von Daniels, 1981). Tectonized early middle Miocene (Zone NN5) or older sediments are disconformably overlain by gently tilted reefallimestones (Quezon limestone) and marl of latest Miocene-early Pliocene age. They are exposed in the area of Quezon City and at the

Regional Geology of Palawan 9

north coast of Balabac Island. The limestones occur often as small carbonate buildups interfingering with the marls. The nannoplankton assemblages within the marls are of low diversity with abundant Sphenolithus abies and few Coccolithus pelagicus, Helicosphaera carteri, Cyclococcolithus leptoporus, Cyclococcolithus rotula, and Discoaster sp., probably due to deposition in a very shallow environment.

C.SEDIMENTARY BASINS

The Philippines hosts 16 sedimentary basins that occupy onshore and offshore areas, wholly or in part. These sedimentary basins cover an area of more than 700,000 square kilometers. Only 10% of the total petroleum resources of the Philippines have been discovered, thus making the country a promising site for petroleum exploration investment.

 1. Agusan-Davao Basin 9. Northwest Palawan Basin

2. Bicol Shelf 10. Reed Bank Basin

3. Cagayan Basin 11. Southeast Luzon Basin

4. Central Luzon Basin 12. Southwest Palawan Basin

5. Cotabato Basin 13. Sulu Sea Basin

6. East Palawan Basin 14. Visayan Basin

7. Ilocos Trough 15. West Luzon Basin

8. Mindoro-Cuyo Basin 16. West Masbate-Iloilo Basin

Regional Geology of Palawan 10

1.NORTHWEST PALAWAN BASIN

ESTIMATED RESOURCES DRILLING RESULTS

Total : Discovered resources are estimated at 942 million bbl oil equivalent while the undiscovered resources are about 1,376 million bbl oil equivalent.

Total number of wildcat wells - 58

AREA: 36,000 sq km, 100 % offshore

The N.W. Palawan Basin is located offshore Palawan Island, Philippines, in water depths ranging from less than 100m to in excess of 1000m. Exploration of the basin commenced in the 1970's with the drilling of build-ups of the Nido Limestone Formation located in the shallow water Nido Shelf part of the basin. This initial exploration phase resulted in a number of small oil discoveries (e.g. Nido, Matinloc) which have since been produced. In contrast to the oil-prone Nido Shelf, exploration wells in deeper water to the west of the Nido Shelf (1982-1994) have discovered mostly gas, notably in the Malampaya/Camago accumulation which is estimated to contain 3.4 Tcf gas. With the exception of Malampaya/Camago, exploration results away from the Nido Shelf have been disappointing and have resulted in few potentially economic discoveries.

The NW Palawan basin is characterizedby both extensional and compressionalstructures. The extensional features areparallel tilted fault blocks andintervening half-grabens. The basin hasa sedimentary fill in excess of 10 kmranging from Late Paleozoic toCenozoic in age.Few source rocks have been penetrated in the basin. In the absence of source rock samples, oil geochemistry has been used to deduce source rock types. Typing of oils in the N.W. Palawan Basin based on biomarkers, sulphur content and carbon isotopes has identified three separate oil families. The majority of hydrocarbons encountered appear to have been derived from a carbonate or marl source rock deposited in a marine environment. Ages of the source rocks are estimated to be Eocene to Lower Miocene. It is interpreted that source rocks have been deposited within restricted rift half grabens and/or isolated restricted intrashelf basins in the Post-Rift carbonate sequence which overlies the grabens.Within the area of Malampaya/Camago charge is derived primarily from a deep half graben located between the accumulation and the Nido Shelf to the east. Estimates of thermal maturity suggest that source rocks in this graben are mature for both oil and gas. Geometry of seismic events in this graben suggests that migration from shallower (more oil-prone) intervals is predominantly towards the Nido Shelf to the east, whilst migration from deeper (more gas prone) intervals is mostly westwards towards Malampaya/Camago, providing a possible explanation for the oil vs. gas discovery pattern made in the area.

Regional Geology of Palawan 11

2.REED BANK(RECTO BANK)

The Reed Bank basin is a bathymetricallyshallow portion located west of Palawan. It forms a plateau-like, stable block withmany shoals and banks most of which are capped by present day coral reefs. Thedominant regional structural pattern is characterized by differential subsidence andlateral tension. The area is deformed by extensional, antithetic, NE-SW to NNE-SSWfaults dipping northwest and by small en echelon, NE-SW transtensional graben.

ESTIMATED RESOURCES DRILLING RESULTS

Total : 440 million bbl oil equivalent Total number of wildcat wells - 4

AREA: 71,000 sq km, 100 % offshore

Area 7 in Reed Bank - or Recto Bank as it is known in the Philippines, is believed to hold huge oil and gas deposits. , according to the Philippines' Department of Energy (DOE), it holds an estimated resource potential of 165 million barrels of oil and about 3.5 trillion cubic feet (tcf) of natural gas. Water depths range between 800 and 1,700 meters.

3SOUTH WEST PALAWAN BASIN

ESTIMATED RESOURCES DRILLING RESULTS

Total : 1,355 million billion oil equivalent

Total number of wildcat wells = 23

 AREA: 44,000 sq km, 100 % offshore

The SW Palawan basin is characterized by a thrust front and at least two major northeast-striking, northwest dipping master fault sets, believed to be transforms related to the opening of the South China Sea. These are offset by north-south striking, high angle faults. Basin fill is composed of Upper Mesozoic to Quaternary marine clastic-carbonate sequences with up to seven km thickness, based on seismic evidence.

Regional Geology of Palawan 12

4.EAST PALAWAN BASIN

ESTIMATED TOTAL RESOURCES: 443 million bbl oil equivalent undiscovered

DRILLING RESULTS: Minor gas shows Total number of wildcat wells = 4

 AREA: 92,000 sq km, 100% offshore

The East Palawan basin is considered a forearc basin that resulted from the subduction of the Palawan Trench with the Cagayan Ridge which is the related volcanic arc (Taylor & Hayes; 1980, 1983). The northeast portion extends near the Mindoro-Cuyo Platform and Panay Island.This basin has 92,000 sq km with maximum sediment thickness of 3.5 kilometers.

RESERVOIR ROCKS:In the Balabac sub-basin, predominantly fine-grained clastic facies were encountered in Coral-1 well. Potential reservoir rocks from Sulu Sea A-1 well in Bancauan subbasin gave porosity estimates of 22-30% and low permeability on the drill stem test conducted on the thin Middle Miocene sandy limestone. Middle Miocene sandstone from Sulu Sea B-1 well sidewall cores showed porosities in the range of 27 to 31%.

5.MINDORO-CUYO PLATFORM

SC73 is an offshore block located in the southern part of the Mindoro Basin – Cuyo Platform, a continental rift basin located offshore the Philippines. It covers around 8,440km2 with water depth ranging from 100 metres to 1,300 metres. There is an existing 2D seismic date set of over 3,000 kilometres covering the block.

The petroleum play types identified in SC73 are reef build-ups, fault blocks and anticlines. The reservoir intervals are Early Miocene to Pliocene carbonates and Early to Late Miocene carbonate and clastics. Source rocks are coaly and organic-rich claystones of Eocene to Middle Miocene. Middle Miocene carbonates and clastics provide the seal for the system.

Oil has been discovered with an Extended Production Test conducted in 1994 at the Maniguin wells near the block. The occurrence of oil seepages in the Mindoro Island region also confirms the presence of an active petroleum system in the area.

The basin covers 58,000 sq km, where 90% of the area lies offshore. Water depths in the basin range between about 200 meters and over 1000 meters. Resources in the basin are estimated to be 832 million bbl oil equivalent including a discovered resource of 25 million bbl oil equivalent (or  25 million bbl oil).

Regional Geology of Palawan 13

ESTIMATED RESOURCES DRILLING RESULTS

Total : 832 million bbl oil equivalent including a discovered resource of 25 million bbl oil

Total number of wildcat wells - 15

AREA: 58,000 sq km, 90% offshore

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D.CITATIONS

Biostatigraphy and Geological Evolution of Sulu Sea http://www-odp.tamu.edu/publications/124_SR/VOLUME/CHAPTERS/sr124_09.pdf

Palawan Province | Mines and Geosciences Bureau Region IV-B MIMAROPA

http://region4b.mgb.gov.ph/?q=palawan-province

Petroleum Potensial Basins of Weat Palawan Basins and Sulu Sea Region http://www.ccop.or.th/epf/philippines/other_pdf/TechnicalReport.pdf

Hydrocarbon Habitat of the N.W. Palawan Basin, Philippines

http://archives.datapages.com/data/ipa/data/044/044001/815_ipa0440815.htm

Philippines offers oil, gas exploration area in waters disputed with China

http://uk.reuters.com/article/2014/05/09/philippines-energy-southchinasea-idUKL3N0NV2BQ20140509

East Palawan basin

http://kalibo.tukcedo.nl/geol_suluseabasin.pdf

http://www.ottoenergy.com/irm/content/service-contract-73-offshore-mindoro-cuyo-block.aspx?RID=313

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