ECA business development vice president Denny McGowan told PetroleumNews.net from Denver that an ECA-Ensign International Energy Services team started the testing program earlier this week.
“They are perforating several zones of interest in preparation for flow testing," he said. "I anticipate first results becoming available soon, certainly before the end of the month.”
ECA, which operates as Westech Energy in New Zealand, used the Ensign Rig 19 to drill the shallow Waitahora well near the town of Wairoa, in licence PEP 38346, earlier this year.
The well found several encouraging signs, including high reservoir pressures, in reservoir-quality rocks over a 70m interval from 1180-1250m measured depth, while drilling down to the 1352m target depth.
McGowan said then the unusually high reservoir pressures, about 3500psi, allowed for potentially big gas reserves at shallow depths. Several conventional cores were also taken from the prospective intervals.
Waitahora-1 is a direct offset to the Kauhauroa-1 wildcat well that in the late 1990s, on an extended production flow test, gauged over 11 million cubic feet per day (MMcfd) of gas and over 70MMcfd during open-flow testing.
Today McGowan said the Houston-headquartered test laboratory, which he believed was Core Labs, had done extensive analysis of the Waitahora cores and ECA was looking forward to integrating those results with the flow test results to determine the details of a forward work program.
“This detailed analysis of the characteristics of the reservoir rock was not done before, with Kauhauroa, and we feel this will be extremely educational and informative,” McGowan said.
Westech would probably shoot some 3D seismic in the next six to nine months in preparation for a second well, he said.
The second well was likely to be drilled late next year or early in 2009 on the flank of the structure to investigate whether there was better reservoir sands in that site.
All of ECA’s six exploration wells and five appraisal wells drilled in New Zealand’s onshore East Coast Basin during the 1990s found significant gas shows. Kauhauroa-1, which flowed from the Kauhauroa limestones, an early Miocene-aged reservoir, and Tuhara-1, discovered hydrocarbons in potentially commercial volumes.