Types of Volcanoes

Shield Volcanoes

Rhyolite Calderas

Cinder Cones

Larch Mountain, Shield Volcano

Shield volcanoes are moderate sized to giant volcanoes
built by an accumulation of very fluid basaltic lava flows, which characteristically have low viscosities.
Because of this, shield volcanoes have broad gentle slopes.
Usually there is one or more vents at the summit,
and often a caldera.
Pit craters are also common, especially along rift zones.
Fissure eruptions are common along the rift zones on the flanks of these volcanoes.
Typically, shield volcanoes are active for thousands to
hundreds of thousands of years.