Geologists recently dated the age of Watersmeet gneiss, a type of rock in the Upper Peninsula, as the oldest in the U.S. Here's what to know.

Edwin Allison collected samples throughout the Pacific concentrating on foraminiferal studies during the 1960s. During the same decade, Albert Engel dredged and collected extensive volcanic and ...

Michigan, Minnesota and Wisconsin all feature ancient rocks known as gneisses — metamorphic rocks banded with various minerals — but an analysis determined that the gneiss in northern Michigan ...

The Secrets of How Life Began May Be Hidden Inside the World’s Oldest Rocks Smithsonian researchers trekked to a remote site in northern Canada to collect four-billion-year-old rock samples that ...

Revise the characteristics of igneous, sedimentary and metamorphic rocks and how they are formed over a long period of time.

Metamorphic rocks are formed in a particular way. A clue to understanding how they are formed is in their name, 'metamorphic', which suggests they have changed form.

The researchers studied magnesium isotope fractionation in eclogite, a metamorphic rock that contains the minerals omphacite and garnet, found in a mountain range in China.

Examples of metamorphic rocks include marble, which originates from limestone and slate, which originates from clay. Slate is dark grey/green in colour and can be split into thin layers for use as ...