In addition, Samson, which had earlier bid for six 320-acre (129.5-hectare) New Mexico blocks, yesterday said it had been successful in acquiring its two top-rated blocks, section 13 East and section 24 West.

They contain five amplitude anomalies, all lying on the same structural and depositional trend as the producing State GC well, in which Samson already holds an equity interest.

State GC had produced 500,000 barrels of oil and had an estimated ultimate recovery of 1 million bbl of oil from the Wolfcamp formation.

Samson said earlier that operators had twice tried to offset State GC but had failed to intersect a porous Wolfcamp zone.

A 3D seismic grid had already been acquired in areas adjacent to State GC in an attempt to understand the distribution of porosity associated with the reservoir.

Mapping of the seismic had successfully delineated, by way of amplitude anomalies, the porosity associated with the producing well compared to that of the dry holes. The six blocks were rated and bid for using this technique.

The company also said using flow data from State GC, a single-well economic case had been developed, using a $US50 per barrel oil price, that indicated a replica of State GC would have a net present value of $US11.1 million ($A14.8 million).

Samson said it was keen to test the amplitude anomalies on its acquired blocks and would be pursuing the acquisition of a suitable drilling rig to achieve this. It had also initiated discussions with the highest bidder of the two blocks that Samson had rated third and fourth.

Meanwhile in Oklahoma, Samson said the Turner 6-14 well, which had been fracture stimulated with 440,000 pounds of proppant and using 5700 barrels of frac fluid, was presently flowing only 320,000 cubic feet per day of gas.

This was lower than expected and it appeared that the Turner 6-14 reservoir had been drained by the adjacent Royal Resources-2 well, which had been onstream since 1988.

However, Samson expected the flow rate to increase as Turner 6-14 unloaded the frac fluid. The operator had designed the fraccing operation to be the largest so far for the field, based on the quality and extent of the reservoir. As such, well performance could take up to 60 days to stabilise.

Samson said the Turner 5-14 well, which was completed in June, had performed better, with production averaging 1.4 million standard cubic feet per day – in line with expectations.

The nearby Hightower 2-23 well spudded on July 1 and was drilling ahead to the planned total depth of 10,700 feet (3272m), after which it would be logged and cased for fraccing, while Hightower 3-23 had been approved and was expected to spud in early September.

“The Turner 6-14 flow rate is disappointing, given the excellent reservoir characteristics that were observed. However, in an infill program such as that being undertaken, it is perhaps expected that one well of the five drilled thus far would intersect a previously drained reservoir section,” said managing director Terry Barr.

“Generally speaking, the infill program has been very successful, with all of the 2005 wells having paid out.”

He said the infill program was establishing a well spacing of 40 acres (90 hectares) and, using that density, an additional three drilling locations had been identified.

An independent reserves report credited the three previous development wells with gross proved developed producing (PDP) gas reserves of 4.5 billion cubic feet which, added to the existing net PDP reserves of 1.2Bcf, gave an assessed net present value of $A5.2 million.

Samson holds 37.5% and 32.5% equity in two sections within the Amber field in the Anadarko Basin in Oklahoma.