Paranta-1 has been cased and suspended as a future Patchawarra gas/condensate producer.
Paranta-1 was drilled as a gas exploration well in mid February to the end of March 2004 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 1 commitment well for PEL 106. The nearest well is Regolith-1, 5 km to the NW. Other adjacent gas wells are Mica-1, 6 km ENE, Welcome Lake East-1, 6.5 km WNW, Double-Jay-1 7.5 km to the SW and Nephrite-1, 8 km to the SE. The Moomba oil and gas processing plant is located approximately 70 km to the SE.
The primary objectives were the gas/condensate charged middle to lower Patchawarra sandstones productive in the adjacent fields. The main secondary objective was the Tirrawarra Sandstone, containing net gas pay in Mica-1 and Welcome Lake East-1. Additional weak targets were possible oil reservoirs within the Birkhead Formation (residual oil has been interpreted in the Birkhead Formation in Mica-1).
Paranta-1 spudded on the 14th February 2004 and drilled to 2848m (D) before the first DST was run to evaluate good gas shows. (One on-penetration drill-stem test was programmed during the drilling phase subject to good shows and sandstone quality). DST-1 was a misrun after the packer seats failed, 20 minutes into the main flow period. A small gas flare was observed whilst reversing out. Drilling continued to 2890m at which depth DST-2 was called. While pulling out to test, the drilling string became irretrievably stuck in the hole after drilling through a possible fault. The drill-string was blown apart near the bit, a short 'fish' was cemented downhole and Paranta-1 was plugged back to 2702m. A side-track was initiated and was kicked-off at 2758.5m in the Patchawarra Formation. Evaluation of another good gas show within the Patchawarra Formation were attempted by drill-stem tests 1ST, 2ST and 3ST but these were all misruns due to unobtainable or lost packer seats. However, DST-3ST (open to the formation for 38 minutes) did recover heavily condensate and gas cut mud during circulation after testing the interval 2872.8-2894.2m (L). Oil fluorescence shows were recorded from sandstones with generally poor visual porosity and common kaolinitic matrix in the lower Patchawarra Formation (from 2904-2958m logger). Maximum fluorescence was 80% from 2934-2937m. These shows have been interpreted to be residual oil only. Drilling continued to a total depth of 3013m, driller and logger (extrapolated) terminating in the Late Carboniferous Merrimelia Formation.
Owing to the somewhat hostile nature of the Patchawarra section to further open-hole testing, and the partial pressure build up and recovery of condensate in the mud following DST -3ST, Paranta-1 was cased for later work-over evaluation. Casing comprised 239 joints 23 lbs/ft 178 mm (7") casing set at to 2979m. Log interpretation has identified gas pay in the Patchawarra Formation. This was the zone targeted by drillstem tests 1ST, 2ST and 3ST.