Borders & Southern Petroleum PLC has spudded the 61/17-1 exploratory well on the PL018 license 140 km south of the Falkland Islands.
The South Falkland basin test is the first of a two-well program and about twice the distance from the islands as the Toroa wildcat drilled by BHP Billiton in 2011. The Borders & Southern well is on the Darwin East prospect more than 300 km south of the Sea Lion discovery in the North Falkland basin and in different geology.
Borders & Southern has shot 2,862 km of 2D seismic and 1,492 sq km of 3D seismic on five production licenses covering nearly 20,000 sq km in which it has 100% interest (see map, OGJ, Mar. 2, 2009, p. 36). The licenses are in 200-3,000 m of water.
Darwin East is a fault-dip closed structure with a Lower Cretaceous sandstone reservoir target. The well will investigate geophysical attributes that include a flat spot, amplitude conformance to structure, and an AVO anomaly. The second prospect is Stebbing to the southeast.
Toroa, a stratigraphic trap 70 km north of the Borders & Southern acreage, is reported to have found good quality sands in the Cretaceous, a thick, good quality source rock interval, and good seals. The source rock, reported to be marginally mature at the Toroa location, is more deeply buried on the Borders & Southern acreage.
The main reason for failure at Toroa is considered to have been lateral seal failure. Borders & Southern noted that its prospects are structural traps expected to have greater trap integrity.