Gravity Gradiometer Systems ? Advances and Challenges

Abstract

Gravity gradiometry has been heralded as one of the top five developments in advancing airborne geophysics in the past decade. There are presently nine deployed gradiometer systems operating in various configurations (partial tensor and full tensor) on numerous platforms in support of global exploration activities. There are also numerous development programs underway with an aim of producing lower noise gradient measurements. We will review the broad scope of developments in gravity gradient instrumentation, with a view toward how the projected improved performance will require greater attention to other error sources. It is easy to see how improved gradient data will benefit the explorationist, yet lower noise sensors alone do not provide the answer. Improved operational capability will need to come from lower sensor and system noise, as well as addressing the external error sources associated with terrain and geology. This paper discusses a wide range of technologies and operational scenarios under development to achieve a robust gravity gradient measurement. The significant challenges associated with improved gravity gradiometer operational capability including vehicle dynamic noise, terrain noise, geologic noise and other noise sources will be a key focus of this paper.