Abstract

Exploration for hydrocarbons in Cambay basin has reached a mature stage, where almost entire area has been covered with seismic survey encompassing both 2D and 3D data. Seismic data has played an important role in understanding the petroleum habitat of the basin. In spite of tremendous efforts, exploration of deeper pays in north Cambay basin has been a major challenge due to presence of overlying thick coal units. These coal units act as transmission filter, generate interbed multiples and mode conversions, alter the wavelet shapes. In order to understand the seismic response of deeper pays, elastic modeling was carried out at several well locations in the study area which suggests that conventional 3D seismic data is not adequate to meet the objective of delineation of reservoir sands as the seismic response of these reservoir sands is very feeble and is contaminated by the presence of multiples and mode conversions. These modeling results also show that there is a very strong mode conversion from top and base of the different coal layers. This indicates that multi-component seismology may be good candidate for exploration of these pays.