Pumice is an example of extrusive igneous rock. The word extrusive means that the magma was forced onto the earth's surface and cooled in a matter of hours. Granite is an example of intrusive igneous ...

This week...another photo from Chile. Here we got a good ol' geologic puzzle...the kind you'd learn in an intro class. Here we can use the intuitive law of cross ...

POTASSIUM–ARGON age determinations have been carried out mainly on minerals with a high potassium content, particularly micas and potassium feldspars, found in intermediate to acid igneous rocks, but ...

There are three types of rock found on Earth. These are igneous, metamorphic and sedimentary. Each rock type is formed in a different way. For example, the rock malachite is mostly made of the ...

Devils Tower in Wyoming is surrounded by myths and mysteries. To the Sioux people, this site was sacred and some of their stories tell how this mountain formed: A long time ago a giant bear chased a ...

Sedimentary rocks are made up of pieces of older rocks (igneous, metamorphic, and sedimentary) and organic remains (shells, bone, etc.). When rocks break apart from erosion they are transported by ...

What’s hiding inside? Why Wyoming’s Devils Tower is still a geological mystery Standing tall at 1,267 feet in Northeastern ...

You might not know it, but Ireland is dotted with extinct volcanoes that have shaped the island we know and love today ...

Pockets of microbes have been found living within a sealed fracture in 2-billion-year-old rock. The rock was excavated from the Bushveld Igneous Complex in South Africa, an area known for its rich ore ...