“Drill Stem Test.No.1 was run to evaluate a pre-drill interpreted a 16-metre gross oil column and corresponding oil-water contact in Rookwood Central-1,” the company said in a statement.
“The recovery of 785 metres of water with an oil film and petroleum odour from this 16-metre interval has confirmed that Drill Stem Test No.1 tested the water leg for the Rookwood Oil Field underlying the oil-water contact.”
Victoria Petroleum said this result confirmed that oil-water contact for the Rookwood Oil Field in Queensland's Surat Basin was higher than the pre-drill interpretation for Rookwood Central-1.
Therefore the gross oil column for the Rookwood field was likely to be smaller than first estimated.
“While the drill stem test result has not proved the high side gross oil column for the Rookwood Oil Field, we are confident that a more modest but commercial oil field is present,” said Victoria Petroleum managing director John Kopcheff.
The drill stem test was conducted over the interval 1,376 to 1,392 metres in the target Boxvale Sandstone Formation. The operator and major partner, Oilex, has gone back into the hole to drill ahead to the total depth of 1,450 metres and then run wire line logs, Victoria Petroleum said.
The current correlation for the top of the Boxvale Sandstone with the producing Rookwood South-1 oil well and Rookwood Central-1 is that as the top of the Boxvale Sandstone is interpreted to be 5 metres up-dip to Rookwood South-1, then there should be a potential gross oil column of about seven metres in Rookwood Central-1.
Wire-line logs and side-wall cores will be run at total depth of 1,450 metres to assist in this interpretation.
After completing drilling at Rookwood Central-1, the rig will move to drill Rookwood–16, a twin of Rookwood-1 with an interpreted minimum 7.5-metre oil column. This well is intended to definitively determine the oil-water contact for the Rookwood field and provide a value for the field’s potential recoverable oil reserves, Victoria Petroleum said.
Rookwoood-16 is 30 metres north of Rookwood-1, the discovery well for the Rookwood field. Rookwood Central-1 is 400 metres south of Rookwood South-1.
Interests in the Rookwood Block are Oilex 59.06%, Victoria Petroleum 29.69% and private interests 11.25%.
