What is Scoria?
March 19, 2013 | Geology.com
Scoria is a dark-colored igneous rock with abundant gas vesicles. It is used to make lightweight concrete and as a landscape aggregate. Nature uses it as the construction material for cinder cones.
Calderas on the Chiltepe Peninsula
February 18, 2014 | NASA Earth Observatory
The Chiltepe Peninsula extends into the waters of Lake Managua, Nicaragua. It is part of an ignimbrite shield with two calderas produced from the ejecta of numerous volcanic eruptions.
Measuring the Size of Explosive Volcanic Eruptions
March 4, 2013 | Geology.com
You have probably heard of the Richter Scale for measuring earthquakes, the Saffir-Simpson Scale for hurricanes and the Fujita Scale for tornadoes. The Volcanic Explosivity Index is used to compare the size of explosive volcanic eruptions.