Mountains, volcanoes and earthquakes
Geography · Key Stage 2 · The School
Plates that move
The Earth's crust is broken into TECTONIC PLATES that move a few centimetres a year — about the speed your fingernails grow. Where they push together, rock crumples upward into FOLD MOUNTAINS: that is how the Himalayas and the Alps were made, and they are still rising.
Volcanoes
Where plates pull apart or one slides under another, molten rock reaches the surface. Look at a world map of volcanoes and they are not scattered — they trace lines, especially the Pacific 'Ring of Fire'. That pattern was one of the clues that led to plate tectonics being accepted.
Earthquakes
Plates do not slide smoothly; they stick, strain builds, and then they jerk. That jerk is an earthquake, and it happens along the same boundaries as the volcanoes. This is why Japan, Indonesia, Turkey and California share a hazard that Britain largely does not.
Plot the world's largest earthquakes and volcanoes of the last century. They do not scatter — they form thin lines: right round the Pacific, up through Italy and Greece and Turkey to the Himalayas, and down the middle of the Atlantic. Now lay a map of plate boundaries over the top and the lines coincide almost exactly. That match is how the theory was confirmed.