Essar Oil to begin CB-ON/3 production by early 2006

Vol 9, PW 9 (11 Aug 05) Exploration & Production

Essar Oil is gearing up to begin production by the end of this year or the beginning of next year from exploration block CB-ON/3 in Gujarat where it has struck modest sized pools of oil and gas.

When the field goes on full production, Essar could produce about 2.5m cm/d gas for a peak period of five years during a field life of 10 years. Each gas producing well will most likely produce about 50,000 cm/d.

As for the oil, we are told the API is 26 and specific gravity is 0.86. Essar could produce 30 cm/d oil from each well.

On full production its believed the field could produce 10,000 b/d. On 11th August, Essar began Phase-II on this block after relinquishing 142-sq km of the original 574-sq km area.

Under the PSC, Essar must drill four wells and shoot 50-sq km 3D in Phase-II. Drilling is expected to begin next month and all four wells should be completed by the year-end.

Target depths will range between 1350 and 1400 metres. Essar has begun preliminary talks for gas sales to factories and other customers in Mehsana the closest big town to the CB-ON/3 discovery.

Another possibility considered by Essar is to supply gas to the Gujarat State Petronet gas grid. GSPLs pipeline from Kalol to Mehsana will be ready by March, we hear.

It will be just 20-km from the Essar discovery. Test results from three wells drilled in Phase-I are encouraging.

Essar struck gas between 1175 and 1225 metres and oil between 1225 and 1275 metres. The gas is sweet and dry.

It seems to be 96% methane, 2% ethane and contains traces of propane, butane and carbon dioxide. Gas pressure is hydrostatic and has been measured at about 1700-psi bottom hole.

The gas column is between 8 and 15 metres thick with a porosity of about 25% and permeability of around 2 Darcies. The sands are clean, with hardly any variation between horizontal and vertical permeability.