Large‐scale tectonic plate motions measured with the DORIS Space Geodesy System

Abstract

We have analysed approximately 3 years of Doppler tracking measurements of the DORIS system on the SPOT2 and Topex‐Poseidon satellites. Absolute velocities of 19 stations of the DORIS network have been computed through a dynamic orbit computation method. These stations are located on 9 major tectonic plates. For 14 stations, relative velocities across 28 plate boundaries involving 8 different plates, agree quite well with the NUVEL‐1 geological estimates, with a correlation coefficient of 0.982 and a slope of 1.00±0.02. This study provides the first space geodesy‐derived motion of the African plate which is based on data taken at 4 stations. Computed rotation vectors for the relative motions between the Eurasian, Pacific and African plates show a good agreement with NUVEL‐1 vectors. For the remaining sites which are typically located close to plate boundaries, measured motions depart significantly from the ones predicted by NUVEL‐1. The site of Fairbanks (Alaska) appears to move anomalously compared to earlier VLBI results.