Tectonic Shift Measurement with Geodetic SAR Processing

We describe a new method for precise, geometrically high-resolution and large-scale measurement of plate tectonics with the aid of radar remote sensing and show first results. For the derivation of the 3D vectors of tectonic displacements two measurement intervals, separated by at least one year are necessary. At each interval several satellite images from different radar viewing angles are obtained, and the 3D-coordinates of ground control points (GCPs) are calculated. By correcting the influence of the ionosphere, atmosphere and earth tides, it is possible to measure the absolute coordinates of ground control points with high accuracy. By comparing the absolute positions of the GCPs of the two acquisition periods, the displacements that have occurred in the meantime can be determined in X, Y and Z. The applications are in the measurement of continental drift, of elevations and subsidence by the melting of very large glacier areas, as well as of tectonic shifts after earthquakes. Furthermore, the continuity of continental drift in earthquake-prone areas can be checked with the help of long-term recording series.