Lava
Flows, Craters of the Moon
Lava
flows are the most distinctive features of lava
plains and shield volcanoes. Lava flows in the
Snake River Plain sometimes traveled for miles
before coming to rest. The relatively low viscosity
of basaltic melts, compared to rhyolitic melts,
results in thin extensive lava flows. Volcanic
forms in the Snake River Plain dramatically
illustrate the contrasting effects of viscosity
between basaltic and rhyolitic melts. The photograph
shows the dark, thin basaltic flows and a large,
steep-sided rhyoloite dome called Big Southern
Butte.
