標題: Airborne Gravity Surveys Over Taiwan Island and Strait, Kuroshio Current and South China Sea: Comparison of GPS and Gravity Accuracies at Different Flight Altitudes
作者: Hwang, Cheinway
Shih, Hsuan-Chang
Hsiao, Yu-Shen
Huang, Chi-Hsun
土木工程學系
Department of Civil Engineering
關鍵字: Airborne gravity;Dongsha Atoll;filter;Kuroshio Current;Taiwan
公開日期: 2012
摘要: We compare the accuracies of GPS and gravity observations obtained from three airborne gravity surveys over Taiwan Island at altitude 5000 m and over Kuroshio Current, Taiwan Strait, and Dongsha Atoll at altitude 1500 m. A kinematic network adjustment was used to determine the positions of the aircrafts. GPS positioning errors are at the decimeter-level, which are not entirely propagated to velocity and acceleration errors due to cancellation of long wavelength errors. Outliers are downweighted in the Gaussian filtering to improve the gravity accuracy, especially at altitude 1500 m. Compared with the upward-continued gravity, the gravity anomalies from the 1500-m surveys show a consistent accuracy of about 3 mgal; the accuracy from the 5000-m survey is degraded, especially over high mountains. The RMS crossover differences at 1500 m and 5000 m are all below 3 mgal, suggesting flight altitudes do not affect the crossover difference. Coherence analysis suggests that the spatial resolvable wavelengths of the airborne gravity range from 4 km (altitude 1500 m) to 6 km (altitude 5000 m).
URI: http://hdl.handle.net/11536/16982
http://dx.doi.org/10.1080/01490419.2011.634962
ISSN: 0149-0419
DOI: 10.1080/01490419.2011.634962
期刊: MARINE GEODESY
Volume: 35
Issue: 3
起始頁: 287
結束頁: 305
顯示於類別:期刊論文


文件中的檔案:

  1. 000308128300006.pdf