Blocks 62/01, 62/09, and 62/13 on offer in the China Yinggehai Basin. [32,925 bytes] One of the Wiriagar wells off Indonesia is shown being tested by Arco. [15,175 bytes] Soco's Pornsiri-1 and B8/38-3 discoveries in Gulf of Thailand B8/38. [35,591 bytes] Three blocks in the Yinggehai Basin were recently opened for bidding, with 29 August being the closing date for bids. Block 62/01, located to the southwest of Chevron's 50/20 GSA, is available for deep rights only (below 2000m). The

Peter Tang

China: Tinggehai Basin bidding opens

Three blocks in the Yinggehai Basin were recently opened for bidding, with 29 August being the closing date for bids. Block 62/01, located to the southwest of Chevron's 50/20 GSA, is available for deep rights only (below 2000m). The western part of this block lies in disputed waters also claimed by Vietnam.

Block 62/09 lies to the east of 62/01 and west of Arco's Yacheng 13-1 gas field. Deep and shallow rights are available for this block. Deep rights only (below 2,000 meters) are available for Block 62/13 which contains a number of shallow gas discoveries. This block also partially covers an area of disputed waters claimed by Vietnam.

Also, Kerr McGee continues to be very active on the PRC continental shelf. On 24 July, the company signed for PSCA 26/06 with CNOOC. The block is located in the Pearl river Mouth Basin and covers an area of 4,500 sq km. At the same time Kerr McGee farmed in to UK independent Cairn's SCA 15/35, and also assumed operatorship. This block also lies in the Pearl River Mouth Basin.

Indonesia: Wiriagar, Vorwata approved

Following a meeting between Arco executives, Pertamina officials, and President Suharto in early September, approval has been given for the immediate development of the Wiriagar Deep and Vorwata gas discoveries, located in the Wiriagar and Berau PSCs in the Bintuni Basin of western Irian Jaya.

The project has been re-named the Tangguh Project (meaning strength). It will be based on spending US$3 billion to develop both fields to support a two-train LNG project as a first phase, initial production expected in 2003.

The proven and probable reserves in the two fields have been assessed independently as being 13 TCF, with a further possible 6.5 TCF. These figures are based on the 11 wells drilled to date on the two fields, namely Wiriagar Deep-1 to 8 and Vorwata-1 to 3.

Australia/Indonesia: ZOCA drilling continues

Drilling in the Timor Sea ZOCA continues apace, with several wells recently completed or underway. Testing of three zones of interest is underway on Mobil's Kelp Deep-1 wildcat, using Diamond Offshore's Ocean Epoch semisubmersible and located in ZOCA 95-18. The well was deepened from its TD at 4,670 meters to 5,175 meters in order to run logs and better evaluate gas shows encountered while drilling.

BHP's Layang-1, located in ZOCA 91-12 about 5 km west of the Kakatua and Kakatua North fields, was spudded on 29 July using Diamond's Ocean Bounty semisubmersible and reached TD at 3,353 meters where it was plugged and abandoned with hydrocarbon shows on 20 August.

The rig then re-located to ZOCA 91-12, where it began drilled a well for BHP. Although cores cut in the zone of interest contained hydrocarbon shows, results of wireline logging proved the zone to be water bearing. The rig-relocated to the south to spud Schilling-1 on 23 August for Petroz in WA-74-P.

Thailand: Focus on Pattani Basin

The Pattani Basin continues as the focus of drilling activity in the Thai sector offshore in the Gulf of Thailand.

Pogo's exploration of the Benchamas Field and its immediate environs in B8/32 continued with the two latest wells to be completed in the current drilling campaign both being abandoned as

gas wells during August. Benchamas-14 and 16 were drilled using Sedco's 601 semisubmersible and were designed to test Miocene sandstones. The wells were two in a series of platform well locators, and no DSTs were planned.

To the south in B12/27, Unocal's Moragot-3 delineation well, drilled using Sedco's Trident XV jackup in 62 meters of water, was plugged and abandoned as a commercial gas well in August after reaching TD at 3,689 meters. The rig then relocated to spud Moragot-4. Moragot-3 was designed to test Miocene sandstones which were gas bearing in the original Moragot-1 discovery, and first delineation Moragot-2. Both were drilling in 1990.

Soco has made two oil discoveries in its B8/38 tract in the Western Basin of the Gulf of Thailand. Pornsiri-1 was suspended as an oil discovery on 11 August after reaching TD at 1,820 meters. The objective Middle Miocene sandstones were oil bearing but no DSTs were conducted.

The Actinia semisubmersible was used to drill this well. After drilling B8/38-2 (dry), B8/38-3 was completed as an oil discovery near the end of August after encountering oil in the Middle Miocene sandstones. This one was oil-bearing at Pornsiri-1.

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