The magma cools down and solidifies, leaving behind a mound of rock, like Traprain Law. Igneous intrusions can be found all around Scotland, not just in Edinburgh and Lothian. Some other examples ...

Extrusive igneous rocks are formed by magma that has erupted onto the surface as lava and then cooled quickly. Obsidian is an example of an extrusive igneous rock. Obsidian has crystals which are ...

The book is comprehensive in its coverage of the processes involved in the petrogenesis of igneous and metamorphic rocks and the implications of these processes ... comprehensive manner. Extensive ...

Igneous rock is formed by the cooling of molten rock ... which generally destroys any fossils that were in the rock before it was metamorphosed. For example, marble is created when limestone is ...

background information on the structure and forces affecting the Earth in relation to rock formation a more practical hand-specimen guide with examples of rock samples commonly found in the United ...