which are heated and compressed underground.Igneous rocks are formed when molten rock from volcanic activity cools down either underground or on the surface.This slow but continuous cycle of rock ...

There are three main types of rock: igneous rock, metamorphic rock ... continuously formed and recycled into other types of rock in a process called the “rock cycle.” This makes the rock record ...

THE GEOLOGY OF the Olympic Peninsula offers a fascinating glimpse into the massive forces of nature that shaped this land into one of the most complicated rock piles in the world.