Alcorn International Inc., Houston, has disclosed a test of another hefty oil flow off Philippines.
Alcorn last month completed its third high flowing delineation well in the West Linapacan area off Palawan Island. Development of West Linapacan field will help boost lagging Philippines oil production, which fell 31% in 1991 from 1990 levels.
Philippines' Office of Energy Affairs (OEA) also outlined other aspects of the country's oil and gas activity in 1991.
Recent drilling successes have redirected the country's focus north to the West Linapacan area from older Northwest Palawan oil fields.
Meantime, two geophysical survey and exploration contracts (GSECs) were awarded in 1991, and two service contracts (SCs) were relinquished during the year.
Several seismic programs were completed last year, and an agreement between Australia and Philippines will yield added seismic data during the next 3 years.
ALCORN DELINEATION
Alcorn's A-3 West Linapacan off Northwest Palawan flowed 7,699 b/d of oil on drillstem test at 7,580-7,620 ft, the Manila press reported.
Alcorn plans to conduct two more drillstem tests before its West Linapacan development program begins in May or June (OGJ, Feb. 10, p. 46).
Alcorn had targeted a flow rate of at least 5,000 b/d in the well to be able to produce a total 15,000-20,000 b/d of crude from the West Linapacan area.
The 2-A West Linapacan early this year flowed at a combined rate of more than 10,000 b/d on drillstem tests of two Miocene Galoc intervals (OGJ, Jan. 27, p. 46). Alcorn also deepened the discovery well, increasing the tested oil column to 1,100 ft from 600 ft (OGJ, Feb. 24, p. 32).
The $48 million West Linapacan development program calls for subsea completions of the three wells that will be connected by individual flow lines to a mooring buoy and tanker.
To achieve commercial production by mid-1992, OEA said the floating production storage and offloading unit in Cadlao field will be moved to West Linapacan (OGJ, Feb. 10, p. 46), thus shutting in Cadlao, North Matinloc, and Matinloc fields for the interim.
OEA said studies are under way to determine if Galoc field can be tied into West Linapacan development (see map, OGJ, Mar. 25, 1991, p. 60). The agency noted it may be possible if the West Linapacan B structure contains oil, warranting installation of a permanent platform.
1991 PRODUCTION
Oil production from Philippines' five active fields averaged 2,975 b/d in January-November 1991, OEA reported. Production during the same period in 1990 averaged 4,304 b/d.
The agency said depletion of Northwest Palawan oil fields caused the decline. Cumulative production from the area is 40.7 million bbl of oil.
Nido field was discovered in 1977 and by yearend 1991 had produced a total 16.4 million bbl of oil. OEA estimates Nido field has about 500,000 bbl of oil reserves remaining.
Cadlao oil field, also discovered in 1977, has produced 11.2 million bbl of oil, and OEA estimates a little more than 300,000 bbl of oil reserves remain.
Matinloc oil field was discovered in 1978, has produced a cumulative 10.4 million bbl of oil, and has about 116,000 bbl of oil reserves remaining.
North Matinloc and Tara fields were discovered in 1987. Cumulative production to date is 2.1 million bbl of oil from North Matinloc and 221,000 bbl from Tara. Remaining oil reserves are estimated at about I million bbl in North Matinloc and 29,000 bbl in Tara.
With most of the Northwest Palawan oil fields shut in to make way for West Linapacan development, reactivation will depend on individual field prospectivity. Nido will maintain cyclic production.
1991 DRILLING PROGRAM
OEA reported 10 wells were drilled in 1991, bringing total wells drilled under the service contract system to 165. Four of the wells drilled in 1991 are discoveries, including Alcorn's 2-A West Linapacan. One is a confirmation well, five are dry holes, and one is still in progress.
Philodrill Corp.'s 1 Octon was drilling at yearend 1990 but was completed in January 1991 flowing 12.5 MMcfd of gas and 1,037 b/d of condensate. Philodrill is evaluating the gas reservoir. The 2 Octon was to have spudded in first quarter this year.
OEA said studies show Octon gas field has recoverable reserves of about 180 bcf of gas and 15 million bbl of condensate.
Fletcher Challenge Petroleum Ltd.'s 1B Calauit off Palawan Island flowed 3,100 b/d of oil (OGJ, Mar. 25, 1991, p. 60), and its 1 South Calauit flowed 3,286 b/d of oil (OGJ, Feb. 10, p. 46). Fletcher pegs recoverable reserves at about 100 million bbl in the Calauit area and plans to follow up with the 1 South Busuanga this year.
Philippine National Oil Co. drilled two onshore wells, 1A San Antonio, a reentry that confirmed natural gas in that area, and 2 San Antonio, a dry hole.
Kirkland AS plans followup drilling and additional seismic acquisition around its 1 Panagatan off South Mindoro, which had noncommerical oil and gas shows.
ARCO's 1 Bangus in North Tanon Strait, British Petroleum plc's 1 Sarap in West Palawan (see map, OGJ, Apr. 23, 1990, p. 29), and Shell Philippines Exploration BV's 1 North Iloc were dry.
OEA said ARCO and BP relinquished their interests in the area.
The 1 North Iloc was an attempt to evaluate Occidental Petroleum Corp.'s 1 Camago discovery (OGJ, Apr. 23, 1990, p. 29).
Other prospects near Camago are being explored to come up with the 2.5 tcf economic threshold needed for commercial development, OEA said, including Shell's 1 Malampaya, which will try to establish continuity with Camago. If added drilling confirms economic viability production could begin by early 1998, OEA said.
EXPLORATION CONTRACTS
OEA said two GSECs were awarded during 1991, while a total of 12 were either under negotiation or pending approval from the Office of the President. OEA awarded four nonexclusive geophysical permits and two service contracts, while two GSECs were relinquished.
Fletcher Challenge is converting its GSEC 49 (see map, OGJ, July 10, 1989, p. 25) to a service contract in preparation for development of Calauit oil field.
Philodrill relinquished its SC 35 in the Sulu Sea, but OEA said negotiations for a GSEC over the same area are under way.
OEA said the Vulcan/Anglo combine relinquished its SC 36 covering Central Luzon but is negotiating a new GSEC over the same area.
Philippines' Basic Petroleum was awarded GSEC 57 covering an area in East Busuanga that is analogous to the Northwest Palawan area, and Grynberg Production Corp. was awarded GSEC 58 covering an area in the Sulu Sea.
Kirkland relinquished its GSEC 52 covering Offshore South Mindoro but remains optimistic about the area, OEA said, and is applying for a new GSEC over the same area.
TransAsia also relinquished its GSEC 55 off Batangas but is negotiating a new agreement over the same area.
BP reassigned its interest and operatorship of GSEC 54 to Crestone Energy Corp., Denver, after poor results from 1 Sarap.
And after conducting a comprehensive study over GSEC 56 covering deepwater Northwest Palawan, BP relinquished that contract.
Nonexclusive geophysical contracts were awarded to Kirkland for Reed Bank and offshore South Mindoro, to Philodrill for Sulu Sea, and to Crestone for Sulu Sea, pending approval of their GSECS.
SEISMIC ACQUISITION
In 1991 three seismic programs were completed, OEA said, totaling 2,916 line km. Total seismic gathered under the service contract system is 160,320 line km.
Fletcher Challenge shot 730 line km of seismic in Northwest Palawan under GSEC 49. Shell conducted a 3-D seismic survey over 130 sq km in Camago-Malampaya area under SC 38, which yielded 1,784 line km of seismic data. Crestone acquired 402 line km of seismic data in the Sulu Sea.
OEA said Kirkland tentatively plans to acquire 1,235 line km of seismic off South Mindoro in early 1992.
Meantime, Philippines and Australia agreed to promote exploration in Philippines, including conducting a seismic acquisition program that is to begin this month or next.
The project includes gathering 2,500 line km of multichannel seismic reflection data, hydrocarbon detection geochemistry data, and other geophysical data over the Southeast Luzon and East Palawan basins. Australia awarded Philippines a $2.14 million grant for the 3 year project (OGJ, Oct. 7, 1991, p. 47).
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