主题：【通告】明年中国可能在印尼有大规模经济开发展开动作 -- wqnsihs

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key facts

Key Data

Name

Natuna field

Location

Greater Sarawak Basin, South China Sea

Blocks

A, B, D-Alpha, Kapak

Shore

700 miles off Jakarta, 140 miles north-east of the Natuna Islands

Discovered

1970

Recoverable Reserves

46tcf

CO2

70%

Full specifications

Natuna gas field is in the Greater Sarawak Basin about 1,100km (700 miles) north of Jakarta and 225km (140 miles) northeast of the Natuna Islands, Indonesia's northernmost territory in the South China sea.

Discovered in 1970 by Italy's Agip, the field is the biggest in Southeast Asia with an estimated 46 trillion cubic feet (tcf) of recoverable reserves, but has been developed only recently.

"Natuna gas field is in the Greater Sarawak Basin about 1,100km (700 miles) north of Jakarta."

A 1980, 50-50 venture in Natuna D-Alpha area, East Natuna, between Pertamina (Indonesia's state-owned petroleum company) and Exxon Mobil Corp of the US, didn't result in production. The 71% CO2 content made gas extraction from the huge 1.3-trillion-cubic-metre area expensive, and development difficult. Despite Exxon's $400m and Pertamina's $60m investments, the Indonesian Government terminated its contract with Exxon in 2007 leaving Pertamina in charge.

East Natuna has been little explored over the last 15 years, mainly due to political disruption, its remoteness, and because discoveries such as Exxon's have proved uneconomic to develop. Reservoirs in the region are in the Middle to Late Miocene reefs, underlain and overlain by deltaic sediments.

PREMIER OIL

In January 1996, Premier Oil bought Sumatra Gulf Oil Ltd giving it a majority interest in the Natuna Sea block-A offshore Indonesia, the Anoa oil field and substantial gas reserves. The company also acquired Discovery Petroleum, and an interest in the Kakap license, part of the West Natuna project delivering gas to Singapore via a pipeline directly over the Gajah Baru field.

The 640km Natuna transportation system is one of the world's longest subsea gas pipelines, delivering 3.4 billon cubic metres annually. The line takes gas from Anoa, Kakap, Belida, Buntal, Tembang and Belanak territories in block B, the neighbouring Natuna Sea block A and Kakap block. In 2002, Premier sold part of its interest in West Natuna.

In 2000, the Gajah Baru-1 discovery well had proven gas columns in eight reservoir sands in the Arang formation near to the West Natuna gas project.

"Discovered in 1970 by Italy's Agip, the Natuna field is the biggest in Southeast Asia."

The well flowed 40mmscf/d in tests, with the maximum rate constrained by surface equipment limitations.

It was drilled to 5,290ft with the Trident 17 jack-up rig using a slim-hole well design. High-quality gas samples were recovered from the flow tests and wire line sampling. Discoveries were also made at Naga-1, Iguana-1 and Ande Ande Lumut-1.

CONOCO

The West Natuna Gas Consortium, a joint venture consisting of Pertamina, Conoco, Premier Oil and Gulf Indonesia Resources, was contracted by SembGas of Singapore in January 1999 for 325 million cubic feet per day (mcfd) of natural gas. A pipeline contract went to McDermott International.

In November 1999, Conoco reported a gas discovery at West Natuna which boosted reserves by about 1tcf. In 2001, the company was developing the Belanak field in West Natuna, intending to export 250mmcfd gas to Malaysia through a 22in submarine pipeline from producing fields to the Belida / Belanch tie-in, with a subsequent 28in line to Singapore.

The project, engineered by Brown & Root Singapore, was located in Conoco-operated South Natuna Sea block B in Indonesian waters, approx 200km off Singapore. It involved the construction of one of the most complex processing systems ever installed offshore, and SharpEye Triple IR (IR3) optical flame detectors.

Conoco used a purpose-built, mobile, gas production jack-up, as on smaller gas fields in West Natuna. Automation supplier Honeywell Industry Solutions were contracted $14.5m to develop an integrated topsides-and-marine automation system for the grassroots Floating, Production, Storage and Offloading (FPSO) facility, the Belanak Natuna, and two wellhead platforms. The Belanak field came onstream in 2004.

"A pipeline linking East Natuna with Sarawak and the Philippines is unlikely to be built in the near future."

The Udang field in the east of Natuna began production in 1980, reaching 36,000bpd from two platforms in 1981, but is now unoperational. ConocoPhillips has five fields in the Natuna Sea and 16 gas fields.

FUTURE NATUNA PROJECTS

Malaysia began importing gas from the Natuna Sea in mid-2003 but a pipeline linking East Natuna with Sarawak and the Philippines is unlikely to be built in the near future due to concerns about expense and security.

Other possibilities include linking gas grids from Thailand to China via an offshore pipeline heading in both directions from a hub at the Natuna gas field, enabling the export of south-east Asian gas to China. An alternative version would link only Indonesia and China.

The interest people put on Natuna Area is mainly due to its strategic location and its economical value, i.e. its hydrocarbon resources. It is here that the biggest gas field in Indonesia was found (Esso's giant "L" Field), which is unfortunately not developed yet. The value of the area is increasing lately with the advent of the West Natuna Gas Project, which is a project selling gas produced from gas fields in the West Natuna Area owned by Gulf, Premier Oil and Conoco to Singapore.

Exploration history of the Natuna Area was started in 1968 when Natuna Sea Block "A" (covering the north part of Natuna Area) and Natuna Sea Block "B" (the south part) respectively were awarded to AGIP and Conoco. In 1974 Conoco succeeded to discover the Udang oil field and AGIP discovered Anoa oil field. Belanak field was then discovered by Conoco in 1975. In 1980s, Conoco discovered some more significant oil fields such as Ikan Pari (1983), Forel (1984) and Belida (1989), and also gas fields such as Bawal (1979) and Tembang (1981). Several other discoveries were made by other companies in the Kakap Block and Natuna Sea Block "A" during the period of 1980s up to 1990s. The most recent one is the Pelikan gas field, which was drilled by Premier Oil in 1999.

Reservoir rocks in the area are mainly the sandstones of Gabus and Arang, and the limestones of Terumbu Formations. Oil is usually found in Gabus and gas in Arang sandstones. The source rock for oil is mainly from the shales of Benua Formation. The gas is mainly biogenic, generated in the Arang Formation. The Keras and Barat Formation act as excellent seals over the Lower and Upper Gabus Formations respectively. In the Arang Formation, the seals are intraformational. The traps in the West Natuna Basin are mostly structural, in the form of inverted anticlines (Figure 5) and wrench-faulted structures. In the East Natuna Basin traps are mainly present in the form of stratigraphic traps such as reefal buildups (Figure 6) or structural traps such as drapes over basement high.

Anoa, Belida and Kakap Fields are the three most prolific oil producer in the West Natuna Basin. The extraordinary thing about the oil produced from these fields is its high quality, which can reach 46-49API, fetching good prices in the market.