摘要
Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove- Compute-Restore (RCR) technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1°and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.
Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove- Compute-Restore (RCR) technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1°and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.
基金
supported by the National Natural Science Foundation of China (41504013,41174062)
the Open Research Fund Program of the Key Laboratory of Geospace Environment and Geodesy,Ministry of Education,China (14-01-03)
the Doctoral Scientific Research Foundation of Guangdong University of Technology(253151010)