The Wellington-headquartered company yesterday told the NZX that the first zone had been perforated in preparation for hydraulic fracturing (fraccing) operations to start later this week.
Austral said that following perforation of a 21m zone below about 4800m, the well exhibited good “injectivity and moderate flowback” against the fluid column within the wellbore – which was “a satisfactory prelude” to fraccing operations.
A mini frac for evaluation purposes would be followed by the main frac, with flows expected around the coming weekend. A report on testing of this first zone would be made after stable flow results had been achieved.
Meanwhile, jet-pump testing of the nearby Cheal-A4 well had produced over 28,500 barrels of oil from the shallow Miocene-aged Mount Messenger and Urenui pay zones. Austral chief executive Dave Bennett said he anticipated successfully employing this technology at nearby Cheal-A3X and other future wells.
Bennett said Austral had a report from Sproule International, of Calgary, which evaluated the Cardiff resource and Cheal reserves within PEP 38738 in accordance with Canadian standard NI 51-101.
The report identified an 11square kilometre area where gas and condensate within the Eocene-aged Kapuni reservoirs were recognised on the basis of Cardiff logs, 2D seismic and other relevant data.
Sproule estimated a 50% probability of gross gas (condensate) in place as 215 bcf (12.8 million barrels) and a 10% probability of 341 bcf (21.5 million barrels).
Sproule booked original recoverable oil at Cheal as 1.511 million barrels of proven, developed and undeveloped reserves and 1.425 million barrels of probable reserves within the Mt Messenger-Urenui pays, according to Bennett.
“This Sproule report provides a useful independent initial assessment of the Cheal and Cardiff fields," he said.
"Both are 'works in progress', and we can anticipate significant changes to these figures in the light of ongoing production performance, further drilling and the planned 3D seismic survey over these fields.”
Austral operates PEP 38738 for both shallow and deep gas, and in late 2003 Bennett said he believed the Cardiff and Cheal prospects could hold 1 tcf or more of recoverable gas.
Bennett today added that Austral had recently completed a seismic program over the Angus prospect within its onshore Taranaki licence PEP 38736. the company was also presently acquiring seismic within its East Coast Basin licence PEP 38330, and would shortly be acquiring about 10km of onshore-offshore 2D seismic in its near-shore Taranaki licence PEP 38492.
The PEP 38738 shallow partners are: operator Austral (36.5%), Cheal Petroleum (30.5%) and International Resource Management (33%). The PEP 38738 (deep) partners are: operator Austral (25.1%), Genesis Energy (40%), Cheal Petroleum (15.1%) and IRM (19.8%).