After the discovery of oil and gas in two recent deepwater wells, Sri Lanka is wooing global companies to tap potential resources off the island’s west and north coast waters.

“We are expecting good response from the global oil and gas companies for the second round of bidding following the two discoveries in Mannar basin by Cairn,” said Petroleum Resources Development Secretariat (PRDS) director general, Saliya Wickramasuriya.

PRDS, the Sri Lankan government agency responsible for overseeing all petroleum E&P-related activities on the island, has organized recent road shows in Houston, London, and Singapore to present potential hydrocarbon leads in the 13 blocks offered in the second round bidding.

The 13 blocks offered are: M-1, M-3, M-4, M-5, M-6, M- 7, M-8 and M-9 in the offshore Mannar basin and C-1, C-2, C-3, C-4, and C-5 in the offshore Cauvery basin.

The blocks in the Mannar basin range in size from 2,714 sq km (1,048 sq miles) to 8,120 sq km (3,135 sq miles) in the deep to ultra-deep waters of the Gulf of Mannar. The ones in the Cauvery basin cover between 2,403 sq km (928 sq miles) to 4,566 sq km (1,763 sq miles) in the shallow waters of the Palk Strait and deep waters in north Sri Lanka. The last date for sub- mission of bids for these blocks is 29 November.

PRDS is also offering six blocks in the unexplored deepwater areas east and south of Sri Lanka to companies to carry out geophysical studies and collect associated seismic data on a joint study basis. The selected company will have two years to collect the data and an option to negotiate a deal with the government for exploration and development of the blocks.

The six blocks are: JS-1, JS-2, JS-3, JS-4, JS-5 and JS-6.

The Sri Lankan authority is expected to award the exploration licenses for 13 blocks by 1Q 2014 and award the six blocks for the seismic studies within the next two months.

Sri Lanka is showcasing the discovery of hydrocarbon shows in two wells in the Mannar basin by Cairn Lanka Private Ltd. to lure the global players.

Cairn Lanka, a subsidiary of Cairn India Ltd., discovered hydrocarbon shows in two of four exploration wells drilled in deepwater SL 2007-01-001 block in the Mannar basin off the west coast. It discovered hydrocarbon sandstone in the first well (CLPL-Dorado-91H/1z) drilled in a water depth of 1,354 m (4,442 ft). A gross 25 m (82 ft) hydrocarbon column in sand- stone between the depths between 3,043 m (9,986 ft) and 3,068 m (10,068 ft) measured depth has been interpreted from log and MDT data to be predominantly gas-bearing with some additional liquid hydrocarbon potential.

Dorado is the first hydrocarbon discovery made in Sri Lanka. The CLPL-Dorado-91H/1z well is the first well to be drilled on the island in 30 years.

The operator made a second discovery at the CLPL- Barracuda-1G/1 well in the same block. The well was drilled to a total depth of 4,741 m (1,555 ft) in a water depth of 1,509 m (4,951 ft) and encountered 24 m (79 ft) of hydrocarbon- bearing sandstone in three zones between the depths of 4,067 m (13,343 ft) and 4,206 m (13,799 ft). The reservoirs were pre- dominantly gas bearing with some additional liquid hydrocarbon potential. The second successive discovery is located 38 km (24 miles) west of the CLPL-Dorado-91H/1z discovery well and approximately 68 km (42 miles) from the Sri Lanka coastline.

The third well, CLPL-Dorado North 1-82K/1, was plugged and abandoned as a dry hole. The fourth well, drilled as part of the second phase exploration plan, encountered high quality reservoir sands but they were water-bearing. The well was plugged and abandoned.

Cairn Lanka is preparing to launch its third phase exploration program in the deepwater block awarded during the first licensing round in 2008.

“The company continues to consider appraisal options for the gas discoveries made and for continuing into exploration phase-III. Monetization of the existing discoveries continues to be evaluated under various development and commercial scenarios. Discussions with the government of Sri Lanka regarding commercial terms and gas pricing are progressing,” the company said in a press release.

The two-phase exploration campaign carried out by Cairn Lanka has revealed the presence of an active petroleum system in the Mannar basin.

“The main result of this (Cairn’s) exploration campaign was the establishment of a working petroleum system in the frontier Mannar basin. Potential deepwater reservoirs are rep- resented by channel-levee complexes, slope fans, and basin floor fans in the Cretaceous. Thick sand packages are present in the Late Cretaceous and Tertiary in the recently drilled wells in the basin, with log-based porosities of up to 30%. The presence of multiple play types, including four-way structural closures, stratigraphic pinch-outs, rotated fault trap, and deep water channel-fan systems are further positive indications for the hydrocarbon prospectivity in this frontier territory,” Cairn India said in a note.

According to PRDS, speculative seismic data of the Mannar basin suggests it has significant potential for large, world-class structural and stratigraphic prospects in the Late Jurassic to Late Cretaceous/Paleocene syn-rift and post-rift sections.

The offshore Cauvery basin, which spreads from India’s southeast coast to Sri Lanka’s northwest, is also considered to have potential hydrocarbon accumulations. Seismic studies reveal that lacustrine and restricted marine shales of possibly Late Jurassic to Early Cretaceous age in Cauvery basin have hydrocarbon source. They also suggest the presence of active petroleum system with source rocks similar to those found in the Indian side of Cauvery basin.

Exploration efforts in the shallow and deep waters of India’s Cauvery basin have resulted in the discovery of oil and gas in more than 30 wells, including Dhirubhai-35 (D-35) by Reliance Industries Ltd.

D-35 was drilled in a water depth of 1,185 m (3,888 ft) and encountered a clastic reservoir with a gross hydrocarbon column of around 150 m (492 ft) of Cretaceous section. During the testing, the well produced 31 MMscf/d of gas with 1,200 b/d of condensate from the main zone and 550 bbl of oil and 1 MMscf/d of gas from the secondary zone. – Contributed by Ravi Prasad