wegener suggested that the positions of the continents were not fixed but that they moved slightly
Later,scientists discovered most of wegener's ideas were right on the mark. They then developed the theory called plate tectonics.
According to plate tectonics, the surface of the Earth consists of a number of enormous plates or sections of rock, each about eighty kilometers thick. The plates float and slowly move at speeds between one to ten centimeters every year. That is about the rate your fingernails grow! Within the Ring of Fire, new material for the Earth's plates is constantly being created as hot liquid rock called magma flows from the center of the Earth up to the ocean floor. All the existing plates on the Earth's surface have to move slightly to make room for the new material.