Validation of seismic data processing and interpretation with integration of gravity and magnetic data

Abstract

Abstract integration of gravity and magnetic data with seismic interpretations provides a definitive means of section validation. Traditionally this has been achieved as a two stage and separate process — seismic interpretation in the time domain and the potential fields model in the depth domain. Recent advances in software technology now enables interactive simultaneous real-time modelling of seismic gravity and magnetic data. In addition to conventional interpretations, modern uses of modelling now includes: quality control of seismic depth conversion, control of the potential field model using offset raytracing; derivation of a high quality depth model as a starting point for processes like pre-stack depth migration or turning wave analyses. Integration too can be used to differentiate between geometrically similar but lithologically different seismic structures. This paper describes the advantages of dynamically linking velocity, density and susceptibility in the modelling process illustrated by three different North Sea geological examples. (a) Depth-velocity modelling of salt structures in the Central Graben. (b) Structural interpretations of the Rattray volcanic rocks in the Outer Moray Firth. (c) Shallow sand channels and velocity models from high resolution aeromagnetic data.