Full Spectrum Gravity — Improving AGG Data Quality at Both Ends of the Spectrum

Abstract

Three major developments provide improvements in the spatial resolution, long wavelength response and noise reduction in airborne gravity gradiometer data. The world’s first commercial strap down gravimeter, sGrav, has achieved the same levels of data quality at long wavelengths as stabilized platform systems. With a repeatability of 0.71 mGal RMS at 300 s filtering, it is ideally suited to augment the long wavelength airborne gravity gradiometer data. The sGrav data is incorporated into the airborne gravity gradiometer processing stream by a modified conforming technique that first converts the gravity data to gravity gradients and then merges the result with the gradients from the gravity gradiometer. This improved process has advantages for conforming gravity gradiometer data to any regional gravity data.

Processing gravity gradient data routinely involves low-pass filtering which limits the spatial resolution. A new processing method increases this resolution by splitting the acquisition noise from the geologic noise and then removing the acquisition noise. This method has reduced noise amplitude densities, in some cases by 50%.