Plate tectonics and continental drift during the Cenozoic era

The theory of plate tectonics rests essentially on paleomagnetism data and on the results of submarine cores which are evidence of continuous sea-floor spreading. Each oceanic plate is connected to the adjacent continent. Its continuous movement (a few centimeters per year) accounts for the hypothesis of “continental drift” put forward by Wegener around the turn of the century and explains the formation of mountain ridges and ocean pits. In connection with the paleogeography of the epicontinental seas, sea-floor spreading allows a better understanding of mammal migrations during the Cenozoic era.