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 ...

Igneous rock Igneous rocks are formed when molten rock (magma) cools and solidifies, with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as ...

During the nearly 14 months that it has spent on the red planet, Curiosity, the Mars Science Laboratory (MSL) rover, has scooped soil, drilled rocks, and analyzed samples by exposing them to laser ...

We often talk about climate change, melting glaciers, or strange landforms. But we rarely think about something that’s always around us– rocks. They don’t make the news, but they’re everywhere. We ...

THE accompanying photograph (Fig. 1) was taken by me some years ago during the construction of the Shirawta Dam, Bombay Hydro-Electric Works, India. It shows a curious fracture surface due to a heavy ...

Scientists report on the analysis of a surprisingly Earth-like Martian rock, discovered by the Mars Science Laboratory rover Curiosity, that offers new insight into the history of Mars's interior and ...