Pumice is an example of extrusive igneous rock. The word extrusive means ... When lava erupts from a volcano, it can be as much as 10 times hotter than boiling water! This is why you have to ...

For example, in the rocks exposed in the walls of the Grand Canyon (Figure 1) there are many horizontal layers, which are called strata. The study of strata is called stratigraphy, and using a few ...