Problems with Plate Tectonics
David Pratt
Space-geodetic techniques, such as satellite laser ranging (SLR), very long baseline interferometry (VLBI), and the Global Positioning System (GPS), provide valuable data on the relative motion between sites on the earth?s surface up to 12,000 km apart. Measurements to date are said to be in generally good agreement with the motions predicted by plate tectonics, and are widely regarded as having confirmed seafloor spreading, subduction, and continental drift.
