Deepwater gas giant discovered off eastern India

Indian and Canadian companies discovered a giant gas field in the Krishna-Godavari basin just off the central Andhra Pradesh coast.

By OGJ editors

HOUSTON, Nov. 7 -- Indian and Canadian companies discovered a giant gas field in the Krishna-Godavari basin just off the central Andhra Pradesh coast.

Reliance Industries Ltd., Mumbai, said four wells indicate that the A-1 accumulation has gas in place exceeding 7 tcf, a figure out to consulting engineers DeGolyer & MacNaughton for confirmation. Recoverable volume was not discussed. Individual well deliverability should exceed 100 MMcfd, Reliance added. Niko Resources Ltd., Calgary, holds 10% interest.

"Integrated 3D seismic and well interpretation indicates that the reserves could be significantly higher," Niko said. Even at 7 tcf in place, A-1 on KG-DWN-98/3 (Block D6) would be India's largest gas field.

Cairn Energy PLC, London, also has sizable gas and oil discoveries on KG-DWN-98/2, which adjoins KG-DWN-98/3 to the west.

A-1 discovery
The four wells and 3D seismic data indicate an anomaly of 177 sq km and a hydrocarbon column of 342 m, Niko said. The A-1 structure is 20 km off the Godavari River delta in an average 900 m of water in the Bay of Bengal. The Miocene reservoir is at 1,850-2,200 m subsea. A-1 is positioned on the closest part of the 1.9 million acre block to shore. Two wells on the structure flowed at rates of 40 MMcfd and 29 MMcfd of gas on cased-hole tests constrained by equipment capacity.

Reliance and Niko won the block in first round bidding under India's New Exploration Licensing Policy. Niko holds 10% interest in NEC-OSN-97/2, farther north toward Bangladesh along India's east coast, and also has an agreement to develop onshore Chattak and Feni fields in Bangladesh, subject to government approval (see map, OGJ, Apr. 22, 2002, p. 48).

Niko also said it received government clearance to proceed with its platform at Hazira off India's west coast and planned to award the construction contract in mid-November.

Area outlook
A-1 could go on line in 18 months and produce 1.4 bcfd of gas in 4 years, reported investment firm Canaccord Capital Corp., Vancouver, BC. It said Reliance would drill one well per month for the next several months, ultimately needing 20 wells for full development at $20 million (US) each. Subsea completions and a pipeline to shore will be needed, but overall development costs haven't been determined.

The analyst noted that one of Cairn's wells reached TD of 2,400 m and flowed at a combined, stabilized rate of more than 81 MMcfd. Cairn has estimated reserves at close to 1 tcf of dry gas in two discoveries and has made preliminary progress with gas marketing. It also has two oil finds on the block.

Cairn has described the "N" and Annapurna gas discoveries and the "P" and M" oil discoveries (OGJ Online, Aug. 20, 2001). Net reserve potential is thought to be at least 200 million bbl of oil equivalent.

A well on the "M" prospect stabilized at 5,998 b/d of oil and 3.87 MMcfd of gas with 1,130 psi flowing wellhead pressure on a 48/64 in. choke. The oil is 35° gravity and similar to that produced at Ravva field to the west and that tested in Cairn's "P" discovery.

More in Drilling Operations