Diastrophism: what moves mountains, what shapes the seas?

Description: Part of the “Science and the earth” series, this film provides an explanation of what scientists know about diastrophism, the forces which shape the earth’s surface. While earthquakes and volcanoes provide some information, much more is still required. Using animated maps and drawings the effects of earthquakes on the crust, mantle and core are shown. Such theories as whether the earth’s crust is floating on a sea of molten rock, whether the surface is shrinking or expanding in area, the origin of the continents and whether currents within the earth cause folding, are explored.