Rossco-1 is suspended as a future Patchawarra gas and condensate producer.
Rossco-1 was drilled as an exploration well in December 2005 to evaluate the hydrocarbon potential of a four-way dip closed anticline situated on the western margin of the Patchawarra Trough in the Cooper Basin. This was a Year 3 commitment well for PEL 106.
The nearest well is Doublejay-1, located 4 km to the north. Other nearby wells comprise the Jack Lake (6 km to the south), Nephrite (7 km to the E) and Smegsy (6.5 km to the SW) Gas Fields. The Moomba oil and gas processing plant is located approximately 50 km to the south-east.
The primary reservoir targets at Rossco-1 were gas/condensate-charged middle to lower Patchawarra sandstones that are productive in the adjacent fields. Secondary targets were identified in the Tirrawarra Sandstone and in the upper Patchawarra Formation.
Rossco-1 was spudded on the 14th of December, 2005. While drilling the Patchawarra formation, one DST was attempted, which was a misrun due to tool plugging.
After wireline logging, and due to hole instability problems, Rossco-1 was cased and suspended to be tested at a later date.
After subsequent testing Great Artesian announced that Rossco-1 flowed gas at a rate of approximately 4.2 million cubic feet per day with associated condensate in the range of 100 to 150 barrels per day during cased hole production testing of the 27-9 sandstone of the Patchawarra Formation.
The program entailed testing of five sandstone intervals interpreted as being hydrocarbon bearing on the basis of wireline geological data and engineering data at the time of drilling. Four of these sandstones lie within the Patchawarra Formation, and one within the overlying Toolachee Formation.
Rossco-1 continues to be evaluated for commercialisation.