Case histories of high-accuracy land gravity gradient measurements

Abstract

The concept of using gravity gradient measurements for gaining knowledge of the subterranean zone is not new. Instruments have been built and field measurements have been conducted over the past 100 years. Improvements in both sensor performance and survey procedures have resulted in the present capability of making high accuracy (sub-Eötvös) measurements in real-world areas of interest. A summary of recent field activity using Lockheed Martin gradiometer systems will be presented in this paper. Recent improvements have resulted in a land-based gravity gradiometer system capable for use in a broad range of land applications, including void and tunnel detection, void characterization, and time-lapse reservoir monitoring.