The Rock Type That Forms at New Seafloor Spreading Centers

Q39: The low-viscosity,fluid lava of hot-spot volcanoes is

Q40: The Volcanic Explosivity Index (VEI)is based on<br>A)

Q41: A phreatic volcanic eruption<br>A) Involves ash only.<br>B)

Q42: To halt a pyroclastic flow,one could use

Q43: Yellowstone National Park is underlain by an

Q45: So far,Mount St.Helens is the only volcano

Q46: The 1991 eruption of Mt.Pinatubo caused global

Q47: A volcano built of many thin flows

Q48: The Pacific Ring of Fire is<br>A) A

Q49: The Yellowstone Park volcanic area is along