IDS Workshop 2006Abstract

A model of present-day plate motions from the DORIS system

Dr Laurent SOUDARIN⁽¹⁾, Dr Jean-François CRÉTAUX⁽²⁾

⁽¹⁾ CLS, Ramonville Saint-Agne, FRANCE
⁽²⁾ CNES/LEGOS, Toulouse, FRANCE

Session theme: Stations coordinates

Abstract

In the frame of the International DORIS Service (IDS), the LEGOS/CLS analysis center (LCA) processes the DORIS measurements from the SPOTs, TOPEX/Poseidon and ENVISAT satellites, and provides to the IDS the weekly station coordinates of the whole network of this satellite positioning system. Based on those measurements, we computed the velocities of 58 sites with linear motions from a 12-year (1993-2004) combined matrix. We present the horizontal motions for the sites in stable plate interiors and for the sites located close to plate boundaries or in deformation zones according to the model of plate boundaries PB2002. From the velocities of 35 stable sites, we propose a model (LCAVEL-1) for the motion of 9 tectonic plates. Poles of rotation and angular velocities are compared to the recent global models: PB2002, APKIM2000, REVEL, and GSRM-1. New insights of the pair Somalia/Africa are also presented. We discuss the displacements of the sites located close to plate boundaries or in deformation zones. In particular, we focus on the Azores Triple Junction zone where the two DORIS stations of Santa Maria and Punta Delgada, located in the vicinity of the theoretical boundary, have continuously observed 4 and 6 years respectively.

 
Corresponding author:

Dr Laurent SOUDARIN
CLS
8-10 rue Hermes
Parc Technologique du Canal
31526 Ramonville Saint-Agne
France
Phone: +33 5 61 39 48 49
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