Skip Navigation

  Button that takes you to the modules and activities page. Button that takes you to the teacher pages. Button that takes you back to the home page. Button that takes you to the Problem Based Learning model. Button that takes you to the references page.Imape map of some Volcanoes puzzle pieces.  Please have someone assist you with this.

Button that takes you to the Types of Volcanoes: page 1. Image that says Types of Volcanoes: page 2.
Button that takes you to the Types of Lava page.
Button that takes you to the Sizes of Eruptions page.
Button that takes you to the Volcanic Eruption Animations page.
Image of a 'Giant' Caldera Volcano.Types of Volcanoes
Two important types of volcano are difficult to recognize, especially when they are very large. The first of these is the "giant caldera" (see left). Calderas, which are simply circular depressions, are found on the summits of many volcanoes. "Giant" calderas are the largest of these: huge craters up to many tens of miles across. Giant Calderas form by collapse (see animation) in gigantic eruptions that spew volcanic rocks out hundreds or even a thousand miles in all directions. Sometimes the calderas are so filled with lava and volcanic ash that there is no recognizable depression at all. These can only be found by carefully locating the big fractures or "faults" in the ground that mark the edges of the caldera. One such caldera nearly fills Yellowstone National Park. In other cases, the edges of the caldera remain as large cliffs or ridges surrounding the central depression. However, the depression is so large that a person standing in the middle of it could hardly see the edges and would only recognize them if they were pointed out. These giant calderas can best be seen in images taken from space, like the one of the Valles Caldera in New Mexico (below,left).

Image of some giant calderas taken from space.  This image links to a more detailed image. Image of a fissure eruption that links to a more detailed image.

Image of a Fissure Volcano.The second type of volcano which is difficult to recognize either from the ground or from space is the "fissure eruption." (shown left). In this type, there is no central crater at all. Instead, giant cracks open in the ground and expel vast quantities of lava that spread far and wide to form huge pools that can cover almost everything around. When these pools of lava cool and solidify, the surface remains mostly flat. Since the source cracks are usually buried, there is often nothing "volcano-like" to see--only a flat plain. The fissure eruption shown above at right was at Los Pilas volcano in Nicaragua in 1952.

[ Types of Volcanoes: page 1 / page 2 ] [ Types of Lava ]
Sizes of Eruptions ] [ Volcano Eruption Animations ]
[ References ] [ PBL Model ]

[ Home ] [ Teacher Pages ] [ Modules & Activities

Button that takes you back to Volcanoes main page.

HTML code by Chris Kreger
Maintained by ETE Team
Last updated November 10, 2004

Some images 2004

Privacy Statement and Copyright 1997-2004 by Wheeling Jesuit University/NASA-supported Classroom of the Future. All rights reserved.

Center for Educational Technologies, Circuit Board/Apple graphic logo, and COTF Classroom of the Future logo are registered trademarks of Wheeling Jesuit University.