Perth-headquartered Carnarvon said Na Sanun-1RD (NS-1RD) had been drilled to a total depth of 990 metres, penetrating the top 30m of the first zone, and that flow testing had so far resulted in production of about 20 barrels of oil per day with a water cut of 76%.

It said the well, in exploration permit L44/43, had been cleaning up over the past three days and pressures, measured at surface, had been increasing.

The well would continue to be pumped and monitored for further decline in water cut and improvement in oil flows.

If oil production could not be improved significantly from the current zone, NS-1RD would be deepened to evaluate the four additional volcanic zones – two of which resulted in lost circulation (indicating potential reservoir zones) in the previously drilled NS-1 well, 16m away.

Carnarvon said it expected the Na Sanun East (POE-9) multi-well appraisal/development drilling program to start later this month.

It said a 110-square-kilometre 3D seismic survey covering the northern half of Na Sanun East oil field and all of the Bo Rang structure was expected to be completed by mid-July.

The L33-D exploration well, in exploration permit L33/43, was drilling ahead towards a planned total depth of about 1200m.

L33-D – the first well to be drilled by the joint venture in the northern exploration permit – is just 1km northwest of the Wichian Buri village and about 6km northwest of, and structurally separate from, the Wichian Buri oil field.

L33-D is a structural closure of about 4sq.km, with all sandstones present below a depth of 500m prospective oil reservoirs.

Strong amplitudes on seismic surveys at about 1100m are interpreted to indicate the presence of volcanic intervals equivalent to those encountered in the Na Sanun area.

Carnarvon said three additional prospects had been identified in concession L33/43 and would be drilled during 2007.