The idea of a dynamic Earth has had a long history. In 1596 Abraham Ortelius proposed that modern Spain and Northern America were at one point attached to Africa, only to have been torn away by earthquakes and floods. Many other naturalists, puzzled by the geographical of distant coastlines, had proposed similar ideas. But evidence was lacking. The discovery of large submerged mountain chains, and later, palaeomagnetism within oceanic rocks, provided geologists with the evidence they needed. Not until after the 1970s did scientists fully grasp that Earth was divided into plates that were, in places, growing apart and in others colliding. Plate tectonics has provided the evidence to interpret how many different types of minerals and rocks had formed.
This PD will take no more than 30-40 minutes of your time. Extra time for Q&A can follow as required.