Description: Composite volcanoes are steep, symmetrical, and often large enough to be
considered mountains. They are built by thousands of eruptions containing
ash debris followed by lava flows.
Description: Shield volcanoes are dome-shaped, have gentle slopes, and are built almost
entirely from fluid lava flows rather than ash and other debris.
Description: Lava domes are formed by lava that is too viscous (resistant to flow) to
flow a significant distance. Lava tends to pile near the vent, and the dome
may grow by expansion from within.
