Author: Debashis Das, Nirupama Banerjee, K.N. Shridhar and A. Siawal
Abstract - Shale oil or gas is a natural oil / gas contained within shale sequences. It is trapped in reservoirs mainly composed of shale with lesser amount of other fine grained rocks. Shale oil/gas generation within shale depends on amount and type of organic material it contains and degree of maturation it is subjected to. Discovery of oil & gas in organic rich shale in a number of basins in North America has given impetus for exploration of shale oil/gas in Indian sedimentary basins. A number of Indian sedimentary basins also have thick shale sections deposited with organic rich sediments over vast areas which may be prospective for shale gas and oil. At this initial stage of exploration it has become very much imperative to assess the shale oil/ gas resource potential of the basin / block. Analysis of the risk & play chance and estimation of risked resource volume is the most important factor. This risked resources gives an idea about the critical factors to be taken care of during exploration period. In this study, an attempt has been made to identify the risk elements, estimate the play chance and assess the unrisked and risked shale oil resources Assessment unit (AU)-wise and Layer-wise.
