Lesson 1
What is magma that reached the surface
Lava
what are the 5 places during a volcano eruption
magma chamber, pipe, vent, lava flow, crater
this is a hole left when a volcano collapses
Volcanic eruptions create landforms made of these
A caldera
lava ash and other materials
the resulting volcanoes sometime create a string of islands called what
an island arch
A mountain that forms in the earth's crust when molten material, or magma, reaches the surface.
A volcano
is a material found in magma that forms from the elements oxygen and silicon
what is silica
Materials can build up around a vent in a steep, cone-shaped hill or small mountain that is called this
Eruptions of lava flow alternately with explosive eruptions of ash, cinder, and bombs. the result is this
cinder cone mountain
A composite volcano
what type of rock forms from thin and runny, fast-moving lava
A.pyroclastic
B.silica
C.aa
D.pahoehoe
D. pahoehoe
active volcano
it could erupt very soon
What do volcanic belts form along
Boundaries of earth's plates
this volcano erupts if its magma is hot or low in silica and has too many different types of lave including pahoehoe and Aa
a quiet volcano
lava flows slowly build a wide generally sloping mountain called this
repeating floods of lava can form this high thing
A shield volcano
lava plateaus
which of the following landforms is formed by magma
A.caldera
B.dome mountain
C.cinder cone mountain
D.composite volcano
B. Dome mountain
dormant
it could erupt in the future
Volcanoes form along mid-ocean ridges where what happens
two plates move apart
is the mixture of hot gases, ash, cinders, and bombs that flow down the sides of a volcano when it erupts explosively
what is Pyroclastic flow
magma that forces itself across rock layers hardens into a what
magma that squeezes between horizontal rock layers harden to form a what
a dike
a sill
magma rises to the surface during an eruption, pressure, on the magma decreases, allowing gas bubbles to what
expand
extinct
it will never erupt again
an area where the material from deep within earth's mantle rises through the crust and melts to form magma
A hot spot
what three terms do geologists use to classify a volcanoes stage of activity?
when a volcano is high in silica it is what kind of eruption
Active, Dormant, and Extinct
Explosive
a mass of rock formed when a large body of magma cools inside the crust
this forms when magma hardens in a volcano's pipe and the surrounding rock later wears away
a Batholith
Volcanic neck
what happens when a volcano is extinct
it will never erupt again
is an area where material from deep within earth's mantle rises through the crust and melt to form magma
a hot spot