Preliminary Geoid Mapping Results by Fugro’s Improved TAGS Airborne Gravity System

English Abstract:

Since 2008, Fugro has been actively developing airborne geoid mapping capability. Now its first generation of airborne geoid mapping system based on the Micro-g LaCoste Turnkey Airborne Gravimetry System (TAGS) is ready to serve its clients. 

In order to determine the available accuracy of Fugro’s improved TAGS system, three test areas that are part of the US NOAA National Geodetic Surveys (NGS) GRAV-D project were chosen for case studies. The first test area is in Louisiana and has topography less than 500 meters in height, but data collected at a high flight altitude about 10 km. The second test area in California has data collected at a variety of moderate altitudes from 6 to 7.5 km, but is challenging because of the presence of mountains up to about 4 km in height. The third test area is over New Hampshire, USA and Quebec, Canada with a mixed topography up to about 1.8 km in height. The data were collected at a flight altitude about 5.5 km.

Preliminary geoid mapping results have been computed for all test cases, and compared to the terrestrial-gravity-based USGG2012 and CGG2013 geoids, to the global geopotential model EGM2008, and to GPS-Leveling results. These tests indicate that Fugro’s improved TAGS airborne gravity system is able to achieve a comparable geoid mapping result to traditional terrestrial methods both in geoidal height accuracy and in spatial resolution.