Reply to ASK-AN-EARTH-SCIENTIST

Subject: Types of Volcanoes

What are the different types of volcanoes?

   Three basic types of volcanoes are recognized by geologists.

  1. Shield, with its broad, gently sloping form, made of once fluid lavas. Mauna Loa is the type example.
  2. Cinder cones, steep sided (25-33 degrees), made of fragments of lava that were spit out of the volcano. Most of these cones are small (100's of meter across, although some get large, several kms). Mauna Kea has some of these cones as does Waianae.
  3. Composite or strato-volcanoes are composed of once pasty lavas and layers of lava fragments (from explosive eruptions). It has gentle to moderate slopes on flanks and is steep near the summit. Usually smaller than shields but larger than cinder cones. Some of these volcanoes, like Crater Lake volcano, have cinder cones on it.
    Diamond Head is a special type of cinder cone because it was formed very explosively. He has a very large crater compared to the rim size. This type of volcano is called a tuff cone. Koko crater is another example of this type of volcano.

Dr. Mike Garcia, Professor
Department of Geology and Geophysics
University of Hawaii, Honolulu, HI 96822


Return to the Ask-An-Earth-Scientist © page