"The sixth well, in the vicinity of the previous five wells where world class gas reserves were discovered, also encountered several gas zones," a senior company official said.

"We are yet to appraise the discovery, which has the potential to revise upward the previous estimates of reserves in the KG-DWN-98/3 block."

The consortium of Reliance Industries and Niko Resources of Canada will drill one or two more wells in the block before appraising the find.

Reliance is also gearing up to drill exploratory wells in Mahanadi basin offshore block MB-OSN-97/2 and Gujarat shallow water block GK-SNJ/1. "An extensive seismic survey has pointed to the presence of oil reserves in Mahanadi basin block while gas reserves are indicated in the Gujarat block," the company official said.