Rialto announced on Thursday the Transocean-owned jack-up rig GSF Monitor had commenced drilling the Gazelle-P4 development well on the offshore Gazelle field.
The well is being drilled to a total depth of about 3200 metres to test the potential of two oil reservoirs and four gas reservoirs in the Upper and Lower Cenomanian sands.
The well is expected to take about 45 days to drill and test and is budgeted to cost $28 million, which Rialto said it was fully funded for from existing cash reserves.
The drilling of the development well follows successful oil and gas flows from the first well in the drilling campaign, Gazelle-P3 ST2.
The well achieved maximum flow rates of 19.5 million cubic feet per day of gas and an unstabilised rate of 760 barrels of oil per day from separate sands within the Upper Cenomanian reservoir during testing earlier this month.
The third and final well in the company’s current drilling campaign will be spudded on the Chouette exploration prospect which is estimated to hold a prospective resource of 84 million barrels of oil and 42 billion cubic feet of gas.
Rialto is expected to make a final investment decision on the Gazelle field development by September this year, with start-up anticipated towards the end of 2013 or in early 2014.
Initial output from the field is expected to average 8000 barrels per day of liquids and 100 million cubic feet of gas per day.