Plates Collide

When two plates carrying continents collide, the continental crust buckles and rocks pile up, creating towering mountain ranges. The Himalayas were born when the Indian subcontinent smashed into Asia 45 million years ago. The Himalayas are still rising today as the two plates continue to collide. The Appalachian Mountains and Alps also formed in this way. (Illustration by E. Paul Oberlander, © Woods Hole Oceanographic Institution)