quiz 3 Flashcards
important volatiles in magma include
water and carbon dioxide
…melting occurs at subduction zones because the down-going plate…
flux ; contains abundant water
which type of magma has the greatest silica content
felsic
magma tends to…
move upward away from where it formed
viscosity controls how …
easily a fluid flows
rhyolite lava
-has more silica than basalt lava
-indicates the tendency of explosive activity
-may freeze in the vent and emerge as spine
-may form a lava dome above the vent
If the volatile content of magma is increased its viscosity will
decrease
All other factors being equal, if a body of magma becomes more feisic, its viscosity will
increase
the eruption of basaltic lava generally creates a steep feature called a lava dome like that now forming in the caldera of mt st helens
false
a batholithe is a …
amalgamation of plutons
what volcanic effusiveness is not a form of lava
lapilli
an irregular-shaped blob like igneous rock body that cooked beneath the surface of earth is a
pluton
volcanic mud-and-debris flows composed of ash debris and water
have often resulted in damage and death to humans and their property
devils tower wyoming, and shiprock New Mexico, are landforms that exist because softer volcano exterior have erroded fasterthan solidified lava in fissures and vents
true
in 79 C.E the citizens of pompeii in the roman empire were buried by pyroclastic debris dervied from the erruption of
mount Vesuvius
