The effects of density contrast surfaces on Airborne Gravity Gradiometry (AGG) data interpretation

Abstract

SUMMARY The accessibility of high-powered computers, plus readily available and detailed topography, allows the explorer to account for the effect of terrain in gravity and gravity gradiometry surveys applied to highlight subterranean density variations. Similarly, accounting for other known density contrasts can further enhance the geological understanding of a survey area. The bedrock/overburden interface, lake depth and snow thickness can be mapped to provide 3D geometric surface models. The gravity gradient responses of these surfaces are presented. Overburden and lakes are shown to have significant influence on the survey data. The effect of snow cover on survey data was found to be negligible. However, it may be important for the next generation of airborne gravity gradiometer instruments.