Offset and angle domain common-image gathers for shot-profile migration

James Rickett and Paul Sava

james@sep.stanford.edu, paul@sep.stanford.edu

ABSTRACT

In order to estimate elastic parameters of the subsurface, geophysicists need reliable information about angle-dependent reflectivity. In this paper, we describe how to image non-zero offsets during shot-profile migration so that they can be mapped to the angle domain with Sava and Fomel's 2000 transformation. CIGs also contain information about how well focused events are at depth, and so provide a natural domain for migration-focusing velocity analysis.