Abstract

Attempts to reprocess vintage 2D seismic data is often a tough task particularly when the seismic data is contained in different line segments shot with varying acquisition geometry. The present paper deals with a case study wherein old seismic data of three different campaigns were reprocessed with dual objective to better delineate the basin margin fault in the Mehsana Block and to improve the mappability of various sequences viz. Kalol, OCS and Olpad in the west of Mehsana Horst whereas of Kalol, Kadi, Linch and OCS sequences in the east of Mehsana Horst of Cambay Basin. Prestack merging of 2D line segments with non-uniform geometry was done by trace header manipulation of picket numbers. The missing trace interpolation was achieved by Kirchoff Prestack Time Migration, which had the dual role of Pre Stack Trace interpolation and Migration. The quality of subsurface imaging brought out by the reprocessed sections has been greatly enhanced by prestack merging and PSTM for better seismic resolution for fault plane identification.