Area Drilling

Feb. 19, 2007


Sangu field, initially estimated at 800 bcf recoverable, has produced more than 400 bcf since going on production in 1998, said Cairn Energy PLC, London, and its Capricorn Energy Ltd. affiliate.

Production has fallen to about 115 MMcfd in December 2006, and Cairn has begun a three-well drilling program. The first well will appraise Sangu South field 4 km southeast of the main field. The second targets a possibly undrained part of Sangu field. The third, Hatia-1, is a vertical exploration well on a potentially large prospect 10 km northwest of Sangu.

Remedial work has begun on some of Sangu’s producing wells in the Bay of Bengal off Chittagong.

Cairn reduced Sangu’s gross booked reserves by 187 bcf to 142 bcf due to several factors.


Emerald Energy PLC, London, was awarded the Helen exploration and production contract area covering 213 sq km in the Putumayo basin.

Subject to government approval, Vetra Energy Group LLC will fund 100% of the initial exploration phase in return for operatorship and an 85% interest.

First phase of the exploration period is up to 16 months, and minimum work program is to shoot 30 km of 2D seismic surveys and reprocess 120 km. A second phase, if entered, requires drilling one well to 10,000 ft.

Georgia Republic

CanArgo Energy Corp. spudded the Kumisi-1 appraisal well projected to 12,140 ft just south of Tbilisi on the Nazvrevi/Block XIII production sharing contract area in the Kura basin of Georgia Republic.

The well is to appraise the Soviet-era West Rustavi-16 Cretaceous gas-condensate discovery. Seismic surveys shot by CanArgo indicate that a large structure may be present. The reservoir performed well on tests.

The drillsite is near the route of the new South Caucasus gas trunkline, and the government has committed to purchase any gas discovered at Kumisi.


Lukoil Overseas Holding Ltd. took a farmout from TOO Zhambai, contractor under the PSA on the Zhambai South and South Zaburuniye blocks in shallow water and the transition zone of the Kazakh Caspian Sea.

Lukoil Overseas took a 25% interest in late 2006 in the blocks, which total 2,000 sq km. An earlier 2D seismic survey led to identification of the Edil, Kosarna, and Karabulak prospects.

Lukoil Overseas said it will implement the exploration project jointly with state KazMunaiGas and Repsol Exploracion Kazakhstan, Madrid.


Tower Resources PLC, London, is preparing to shoot a 2D seismic survey later in 2007 over a large structure on its acreage in the Atlantic off northern Namibia.

The company holds blocks 1910, 1911a, and 2011a along the southern flank of the Walvis Ridge.

An organic geochemistry study confirmed that three of four potential source rocks are likely to be mature with large areas at peak maturity, the company said. A sea surface oil seep study indicated the possible presence of natural liquid hydrocarbon slicks at surface south and east of the Dolphin graben, the deepest sedimentary sequence on the licenses.

AVO analysis of six selected seismic lines highlighted the potential for commercial gas reserves in the northern part of the licenses, mainly in a large structure west of but adjacent to the deepest kitchen area of the Dolphin graben.

Nova Scotia

PetroWorth Resources Inc., Calgary, retained consulting geoscientists to evaluate the geological and geophysical components of the petroleum systems on the Ainslie Block in southwestern Cape Breton Island, NS.

PetroWorth has 100% exploration and development rights to 383,000 acres on the block.

The same consultants found in a 2004 study that the block’s geology is similar to that of McCully gas field and Stoney Creek oil and gas field in New Brunswick. The new work will include collection of 200 soil gas samples from depths of 1.4 to 1.6 m, which will assist in the design of a seismic program.

Numerous oil seeps have been observed along the western shore of Lake Ainslie, and the widespread distribution of the Strathlorne formation on the block is of particular interest to oil and gas explorers because of its similarity to the commercially productive Albert formation (Mississippian Horton Group) in New Brunswick, PetroWorth said (OGJ Online, Apr. 19, 2005).

South Dakota

Spyglass Cedar Creek LP, private San Antonio independent, found gas in Cretaceous Shannon sand at two wells on the South Cedar Creek project in Harding County, said participant Gold Point Energy Corp., Vancouver, BC.

The Shannon sand pay zone found in the Spyglass State 4-35 well in 35-18n-4e and State 3-30 wells four miles apart is similar to that found at West Short Pine Hills field 12 miles to the west. State figures show that field has produced 23 bcf of gas, Gold Point said.

Spyglass is operator of the 63,500-acre project, on which a proprietary seismic method is being used that has identified numerous Shannon development locations. More seismic surveys are being acquired.

Texas (North)

Morgan Creek Energy Corp., Dallas, plans to explore for gas in Mississippian Barnett shale in McLennan County, Tex.

The Boggs-1, in Morris Moore Survey, is projected to 8,500 ft. The location is on a 40-acre unit less than 1,500 ft from a gas pipeline.


The 2007 program calls for drilling 280 wells using eight operated and four to six nonoperated rigs in Greater Natural Buttes gas field in the Uinta basin, said Anadarko Petroleum Corp.

Net production climbed 33% in 2006, averaging 206 MMcfd in the quarter ended Dec. 31 and peaking at 216 MMcfd during the quarter.

Anadarko drilled three 20-acre pilot infill wells in the quarter to evaluate recovery potential in the more developed areas of the field, now on 40-acre spacing.