Rossco-1 was drilled to a total depth of 3050 metres and terminated within the Tirrawarra Formation. The well has intersected several interpreted hydrocarbon bearing zones within the primary Patchawarra Formation as well as within the Toolachee and Tirrawarra formations, the company said.
“Rossco-1 is being cased and suspended as a potential future gas and/or oil producer,” Great Artesian managing director Ray Shaw said this morning.
“Independent interpretation of wire-line logs, including a comprehensive formation pressure dataset, has confirmed the likely presence of several combined gas and or gas/oil bearing zones. Details of interpreted net pay zones will be released once evaluations have been completed.”
Following the mechanical failure of open-hole drill stem test (DST) one, the company said it had decided not to attempt any further open-hole DSTs. Instead, it would design a cased hole production testing program to determine the specific nature, quantity and flow rates of hydrocarbons within several net pay zones.
Cased hole production testing will take place later in the year once a suitable work-over rig has been contracted. The Century Rig-3 used to drill Rossco-1 will shortly be released and move to the Udacha-1 location.
Rossco-1 is about 6km north of the Jack Lake Gas Field, 5km west of the Nephrite Gas Field, 8km south of the Paranta-1 gas discovery and 7km northeast of the Smegsy-1 new gas discovery.
The well was fully funded by farminees.
Participants in the Rossco-1 well are Great Artesian (operator) 50%, Energy Investments Limited 37.5% and Enterprise Energy N.L. 12.5%.
