(EnergyAsia, March 30) — UK’s Cairn Energy said the N-V oil field about 18km to the west of Mangala off the Indian state of Rajasthan has been appraised and could hold between 250 and 350 million barrels of oil.
The N-V extension area of 856km? was awarded to Cairn by the Indian government in January 2005 on the basis of the N-V-1 oil discovery made in August 2004. The first N-V appraisal well, N-V-1St, was drilled 750m from the discovery well. The N-V-2 and N-V-4 wells have now confirmed further extensions to the field.
Cairn said the N-V-1ST appraisal well tested oil from a single zone in the main Fatehgarh producing reservoir. The well flowed 1,050 barrels per day (bopd) of 25 degree API oil on a 48/64 inch choke. The N-V-1ST well will now be suspended as a potential future producer.
A vertical second appraisal well, N-V-2 has been drilled from a new surface location three km to the north of the N-V-1 discovery. This down dip well, intersected the oil water contact (OWC) as planned and encountered 175m of net high quality reservoir sands with 54m of net oil pay. Selective testing of individual zones within the main reservoir section was undertaken.
The first zone close to the OWC flowed 21 degree API oil into the test string. The second zone tested 210 bopd of 24 degree API oil. The well has now been suspended as a potential future producer.
A deviated third appraisal well, N-V-4 has been drilled from a new surface location five km to the north of the N-V-1 discovery. This well, designed to define the northern limit of the accumulation, encountered 369m of net high quality reservoir sands, which equates to 130m of true vertical pay. The well is to be tested and then suspended as a potential future producer.
The company said: “A well, N-V-3, drilled on a separate fault structure six km to the west of the N-V field was plugged and abandoned. Further appraisal drilling is planned and a 3D seismic survey over the N-V field will commence shortly.”
Cairn’s CEO Bill Gammell said: “The N-V field is now defined by four wells. While further appraisal is required, these well results confirm N-V as a significant field.”