A compound is a substance that contains two or more elements close elementA pure substance that is made from only one type of atom. Elements are listed on the periodic table. Elements cannot be ...

A weathered sign in the Minnesota River Valley proudly proclaims: “World’s Oldest Rock.” Erected in 1975, it marks a 3.8-billion-year-old gneiss — or so scientists thought.

There are three main rock types: igneous, sedimentary and metamorphic. These rocks are made of minerals ... There are many ...

New Curtin-led research has revealed that water played a far bigger role than previously thought in shaping Earth's first ...