That’s the channel inside a volcano that opens up to the surface. As it cools it becomes a very hard type of igneous rock. This one first formed over 350 million years ago. Then, millions of ...

Igneous rocks form when magma cools underground or erupts at the surface as lava. The magma rises into the Earth’s crust, where it can get trapped underground or erupt from volcanoes as molten lava.

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The class can give an erupting-volcano hand action or a trembly-earthquake action to answer. Volcanic rock is formed when lava or magma cools down and becomes a solid. We call this type of rock ...

Beaches around the world come in many colors, from the familiar golden and white sands to rarer hues like pink, red, and even ...

Areas of expertise My research concerns quantitative studies of geological processes using a combination of field studies, laboratory experiments, analytical studies and theoretical modelling. My main ...