A new methodology for 3D survey design

Abstract

There are two main problems in designing a 3D seismic survey. Firstly, a survey geometry needs to be established that will handle signal correctly—in terms of resolution and amplitude fidelity. Secondly, the same survey geometry must somehow effectively attenuate various types of noise that will be present. The design process described below achieves these two goals (record signal in an optimum way and attenuate noise as much as possible). The process may be applied to any 3D survey regardless of subsurface complexity and survey location. The method is applicable to land, marine, and OBC acquisition. Some example details in this paper (notably, parts of step 9 and all of steps 11–14) pertain more to land and OBC geometries than to marine (parallel) geometries. Nonetheless, steps 11 and 12 still apply to marine geometries with small changes to accommodate the line spacing employed there. The analysis of noise and migration impulse response is just as important to a marine survey as it is to a land survey.