Improving the velocity field in South and South-East Asia: The third roundof GEODYSSEA

In the framework of the GEODYnamics of South and South-East Asia (GEODYSSEA ) project a network of 42 stations was observed by GPS during two field cam paigns in 1994 and 1996. BKG and GFZ realized a third observation of the co mplete network in 1998. The data was analyzed independently by two analysis centers and a precision of the coordinate solutions was found to be 4-7 mm for the horizontal, and 10 mm for the vertical component. Subsequently, th ese campaign solutions were merged into one unique solution, which was accu rately mapped into the International Terrestrial Reference Frame of 1997 (I TRF97). The global accuracy of this solution with respect to ITRF97 is of t he order of 10 mm, while the resolution of the relative horizontal velociti es is estimated to be at the level of 2-3 mm/yr. Comparison of the new solu tion with the previously published GEODYSSEA solution indicates, that impro ved results for the motion of Sundaland, South China and the overall deform ation in the area could be found. Improvements are due to the increased tim e span and due to a better connection to and the advances in the ITRF refer ence frame. The new set of coordinates and velocities is used as the basis for scientific interpretations, which have been and will be published in se parate papers.