The CASA'93 GPS campaign for crustal deformation research along the South Caribbean plate boundary

The results of the 1993 GPS campaign in the Central and South America (CASA) project are presented. 21 stations have been observed along the Boconó-El Pilar fault system in Venezuela. By simultaneously occupying a fiducial site at Richmond/Florida the regional Venezuelan network is related to the International Terrestrial Reference Frame (ITRF). Several alternatives in the evaluation procedure are discussed. The accuracy of the final solution is about ± 5 mm in latitudinal and in longitudinal position components, and ± 10 mm in vertical direction. A comparison with the 1988 survey of five identical stations shows coordinate shifts of stations on both sides of the Boconó fault in rough accordance with predictions of the Caribbean and South American plate motions.