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Tectonic plate motions
Centralized ground reception and processing of measurements, and unattended ground location stations, make DORIS well suited to monitoring movements in the Earth's crust. The diagram below shows the results obtained by the LEGOS/GRGS space geodesy laboratory from absolute measurements acquired by the permanent network of DORIS stations. Compare this with the predictions from the Nuvel1 geological model, representing tectonic motion over the last two million years. As expected, sites near tectonic plate boundaries (not shown) are where the most striking differences relative to the model appear.
At regional scale, several deformation monitoring networks have been set up along the Asal Rift in the Republic of Djibouti, and near the major faults in Chile and the New Hebrides off New Caledonia.
Vertical displacement
Permanent observation stations use DORIS to measure the velocity of vertical displacements to within a few millimeters a year. This is a major step forward, as until recently the lack of suitable technologies and measurements restricted observation of movements in the Earth's crusts mainly to horizontal displacements. Today, scientists are very keen to have data on vertical motion, for example coastal movements to study sea level variability.
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