Research on rapid surveying and mapping of outfield absolute gravity based on vehicle-mounted atomic gravimeter

Abstract

The information about Earth’s gravity field is an important basic information necessarily for geodesy, geophysics, geodynamics and other disciplines. The mapping of gravity field is an effective mean to obtain the gravity field information. Compared with the surveying of gravity field based on satellite, ship, and airplane, vehicle-mounted gravity mapping has advantages of strong flexibility, high spatial resolution and high accuracy. A short baseline or a small-scale gravity field mapping can be realized based on the combination of relative gravimeters and the high-precision absolute gravity reference point. However, this method is not suitable for the situation of a long baseline or a large-scale gravity field surveying due to the drift of relative gravimeter. In this work, a vehicle-mounted system for rapid surveying of the absolute gravity field is built up based on a miniaturized atomic gravimeter. The inner precision of the instrument is evaluated to be 0.123 mGal, and the outer precision is 0.112 mGal in a field test which contains 12 points for 3 km distance. Furthermore, with this system, the absolute gravity data are obatined within 2 min for adjusting and 5 min for measuring in downtown for each measured point. A rapid surveying of absolute gravity field for 19 points is carried out and the route covers 24 km. The inner precision of the instrument is evaluated to be 0.162 mGal, and the outer precision is 0.169 mGal. Finally, the free-air gravity anomalies obtained from the measured data of atomic gravimeter and the fitting results of satellite gravity model are analyzed, and it is found that the trends of changing are basically consistent with each other. This paper provides a new proposal for the rapid surveying of the absolute gravity field.