Status of Hydrocarbon Exploration in Western Offshore Basins, India

Following the discovery of Bombay High field in 1974 by OiZ & Natural Gas Commission about 60 oil and gas strikes have been made including a couple of giant fields.

Western offshore comprises five contiguous sedimentary basins all of which are under active exploration. Hydrocarbon resources of 9.5 billion tonnes have been prognosticated in the area upto 200 m isobath, off the west coast of India. About 35% of these have already been established and sufficient scope exists for the continued thrust on exploration.

Two owned survey vessels capable of carrying out state of the art geophysical surveys coupled with inhouse computer facilities and expertise have dispensed with foreign dependence on seismic data acquisition, processing and interpretation faced in the seventies. Advanced techniques of 3-D surveys and evaluation of reservoir parameters from seismic have alteady found place for subtle exploration and exploitation needs.

Today Western offshore is the most active drilling area of the country. Ten offshore rigs owned by ONGC and 18 charter hired rigs are operating. About 250 km per year of exploratory and development drilling is being carried out currently which is likely toincrease 11/2 fold during the Eighth Five Year plan.

Starting from a meagre 0.4 MMT per annum the current production rate of over 20 MMT has been achieved from Western Offshore which-accounts for about 65% of the country's oil from indigenous sources.