if th
Large plutons that can cover an area as large as 100 km2 are called
bath something
Magma that is rich in feldspar and silica is called
felsic
An area of volcanic activity far from a tectonic plate boundary is called a(n)
hot spot
which of the following island is cut into two parts by fissues
iceland
Volcanic eruptions may be signaled by
A change in earthquake activity
when oceantic lithosphere subducts beneath oceanic lithosphere
An island arc forms
volcanic dust ash blocks bombs and lapalii are all
pyroclastic matierls
three events thay might signal a volcanic eruption include a changes in earthquake activity the formation of bulges on or near the volcanos and
a change innn gas emitted
the eruption of mount st Helena was
an explosuve eruption
which of the following doe NOT signal a volcanic eruption
an increase in thunderstorms near the colcano
A large depression formed by the collapse of a volcanic cone is called a
caldera
which of the following is not a major volcantic area
central contintental plains
large pyroclastic particals that are then 64 mm
lapiis
Magma that is rich in magnesium and iron is called
mafic
quiet volcantic eruptions commonly result from
mafic magma
which of the following is NOT a major type of volcanic cone?
mantal pluma
the three primartly tetonic se4ttings are zones near convergent and divergent plates,subduction zonrs and
mid ocean riges
which of the following areas in both is a major earthquake zone and a major volcanic zone
pacfic ring of fire
When an underwater volcano erupts, the magma cools quickly, forming
pillow lava
composite volcanos are also known as
stratovolcanos
if the temperature of rock rises above the melting point of the minerials the rock is composed of
the rock will melt
what forms on the ocean floor in a subduction zone?
trench
a charctestic of lava that determines the force of a volcanic eruption is
viscosity
pyroclastic mateiral that is less then 0.25 mm in diameter is called
volcanic dust
any activity that involves the movement of magma on earths surface
volcansism