Tectonic setting of PapuaSimandjuntak and Barber (1996)

Papua (1) Papua contains a number of basins, Birds Head of Papua has been a

focus of exploration. Two basins in the Birds Head, the Salawati and the Bintuni basins, are proven hydrocarbon provinces.

Papua shows excellent hydrocarbon potential. Miocene carbonate plays previously thought to be exhausted in the Salawati basin may have a new lease of life. The large and undrilled Kais reefs exist to the offshore area south of the Birds Head.

Carbonates of the New Guinea limestone group dominate the section from from the late Paleocene to late Miocene. These Miocene carbonates are areaaly extensive, occurring throughout the Birds Head and making up the high peaks of Central Papua.

The recent Mesozoic gas discoveries in the Bintuni basin open up a whole new Mesozoic play for the Bintuni basin and other areas in Papua.

Awang H. Satyana (2005)

Papua (2) There has been very little exploration in the Papua thrust fold

belt to date, but a similar geology to the Papua New Guinea (PNG) central fold belt is expected, where oil and gas are reservoired primarily in upper Jurassic to lower Cretaceous clastics, and trapped in complex thrust associated anticlines. Conoco reported oil and gas shows in Kau-2 drilled in the Warim block of eastern Papua. Potential reservoirs also include Kais-formation-equivalent limestones (Darai formation in PNG). Potential sources include the Miocene shales and Jurassic Kopai marine shales.

Awang H. Satyana (2005)

Papua (3) The Waipoga-Waropen basins in northern Papua contain active oil and

gas seps. Abundant reservoir facies include a thick succession of Miocene-Pliocene Markats formation and overlying Mamberamoformation deltaics and turbidites. Biogenic gas discovery in Niengostructure will be appraised in coming years.

The successes in Seram also hold hope for tectonically complicated areas tha have been subjected to intense compression. These include the papua fold belt that continues east into the papuan fold belt of PNG, where a string of structurally complex oil and gas accumulations was discovered in the 1990s and, the Lengguru fold belt where deep burial may have resulted in the maturation of even relatively young Tertiary sources.

Awang H. Satyana (2005)

Tectonic Setting of West Papua

Lundin Sareba (2000)

Main structural elements and petroleum basins of Papua and SeramLivingstone et al. (1993), Sutriyono et al. (1997), Fainstein (1998)

Lundin Sareba (2000)

Salawati Basin (1) The basin is a foreland basin in front of Australian continent fragment,

terminated to the north by Mio-Pliocene Sorong Fault. The Sorong Fault has strongly controlled the geology of the Salawati

basin since Mio-Pliocene (Satyana, 1999), including : the reversal of basin polarity from southwards depocenter since

the Paleozoic to late Miocene, into northwards depocenter since Mio-Pliocene,

sedimentation of Pliocene Klasaman formation, generation and migration of hydrocarbons, deformation of the Salawati basin.

Early-Late Miocene Kais reefal carbonates have been a main objective of the basin since 1930s. All present oil production come from this reservoir. Good quality reservoirs of carbonates are performed mainly by Walio, Kasim, and Matoa oil fields.

Awang H. Satyana (2005)

Salawati Basin (2) Re-interpretation of Kais carbonate sedimentation (Satyana, 2003)

from previous interpretation (Gibson-Robinson and Sudirdja, 1986) proved to open new opportunities from this mature objective.

Geochemically proven source rocks are Klasafet shales deposited in lagoons between the Kais reefs, and interbedded Kais marls within inter-reef environments (Satyana et al. 2000). Pliocene Klasaman and pre-Tertiary source rocks are indicated to have generated oil and gas in northern and southern area, respectively.

Post-Kais reservoirs (Pliocene Intra-Klasaman sands) and pre-Kais reservoirs (late Oligocene Sirga clastics, Eocene Faumai carbonates, and pre-Tertiary siliciclastics) are under-explored objectives of the basin. Proven play of Mesozoic sands in the nearby Bintuni Basin has boosted pre-Tertiary venture in the Salawati basin.

Remaining large and significant hydrocarbon province with Kais and Intra-Klasaman sands potential occur in the under-explored area of the Sele Strait and west offshore of the Salawati Island.

Awang H. Satyana (2005)

Satyana et al. (2000)

Stages in the development of the early Miocene Kais formation carbonate buildups, Salawati Basin Livingstone et al. (1993)

Formation of present Salawati Basin by polarity reversal

Satyana et al. (2000)

Netherwood (2000)

KA

I

S

/

K

L

A

S

A

F

E

T

KLAS A

MAN

deep-water basin

deep-water basindeep-water basin

oil window

depocenter

Reversal of Salawati Basin and generation of petroleum Satyana et al. (2000)

Satyana et al. (2000)

RIM SYNCLINE

BASE LOWER KLASAMAN

TOP KAIS

DIA

PIR INTR

A-KLASAMAN

SENW

SORONG FAULTSORONG FAULTZONEZONE

Satyana and Setiawan (2001)

0 2 4 km

Foredeep of the Sorong Fault, Salawati Basin, site for biogenic gas acummulation

Bintuni Basin Oil was first discovered in Miocene carbonates of Kais equivalent age in

the Wasian and Mogoi oil fields in 1939. Up until 1980s these carbonate buildups had been the only tested play in the basin.

The Wasian and Mogoi oils are sourced from the Permian Aifat formation shales (Chavallier and Bordenave, 1986).

In 1991, Occidental drilled the Roabiba-1 well and discovered gas in Jurassic sandstones. This opened up a new play that led to the ARCO/BP discoveries of the giant gas fields until late 1990s of Wiriagar deep-Ubadari-Vorwata (collectively now called as Tangguh complex, named after Tangguh gas project) in Paleocene turbidites and Jurassic to Cretaceous Kembelangan formation fluvio-deltaic sands.

British Gas also drilled through the existing Mogoi oil field and discovered further gas reserves in Permian Aifam sands.

The Bintuni basin Jurassic gas reserves are also probably sourced from the Permian Ainim formation. There may be input from the Triassic to lower Jurassic Tipuma formation and/or contribution from Jurassic to Cretaceous lower Kembelangan group (Netherwood, 2000)

Awang H. Satyana (2005)

Pertamina and Corelab (1998)

Discoveries of Tangguh giant gas fields, Berau Bay, Bintuni Basin

Typical Log of Roabiba sands

Seismic section across Tangguh fieldsCasarta et al. (2004)

Barrett (1997)

Lengguru fold belt Papua

Hobson et al. (1997)

Jensey oil seep

Petroleum possibility of Lengguru Belt, PapuaLundin Sareba (2002)

Exploring thrust fold belt of PapuaMcConachie et al. (2000)

Structural elements of Central thrust belt of Papua Hobson et al. (1997)

Hobson et al. (1997)

Fields at the Central Ranges of Papua Schroder et al. (2000)

Eisenberg (1993)Fields at the Central Ranges of Papua

Stratigraphicsuccession of Northern Arafuraplatform

Pertamina and Robertson Research (1992)