Most mountains on Earth occur within relatively well-defined, narrow belts separated by wide expanses of much lower-lying ground. Their distribution is not random but is caused by the now well-underst
Our world is made of rock. Those who live in a landscape where rock outcrops are obvious will have wondered about the kind of rock they are looking at and how they came to be where they are now. Graha
The continent of Europe, as a recognizable geographic entity, attained roughly its present shape around 20 million years ago. Even since then, the European coastline has undergone significant changes,