Plate Tectonics
what is the area between two plates know as?
plate boundary
Which type of volcano is the largest on Earth?
Shield Volcano
strato volcanoes
what is the top layer of Earth?
the crust
Define magma:
molten material beneath earths surface
what are the two types of crust on Earth?
oceanic and continental
Where do strato volcanoes typically form?
Subduction zones
where do shield volcanoes form?
hot spots
which layer of the Earth is the thickest?
the mantle
Define lava:
material ejected from a volcano; solidifies on Earths surface
what are the three types of plate boundaries?
1. transform boundary
2. convergent boundary
3. divergent boundary
which volcanoes have pyroclastic flows?
strato volcanoes
which volcano is described as being tall, cone shaped, and having steep sides?
strato volcano
What state of matter is the inner core?
solid
Define subduction zone:
area where an oceanic plate meets a continental plate; oceanic plate sinks underneath the continental
what type of natural disaster occurs most commonly at transform boundaries?
earthquakes
what causes an eruption to be explosive?
gas content and viscosity
why do volcanoes that form on hot spots eventually go extinct?
plate tectonics shift the volcano away from the magma source
how do scientists study the underlying layers of the Earth?
seismic waves
Define viscosity:
why does the oceanic crust sink beneath the continental crust at a subduction zone?
it is less dense
describe the 4 main aspects of a pyroclastic flow
-extremely hot
-very fast moving
-gas and lava
-explosive
where is the magma source for a strato volcano?
the melting oceanic crust that was subducted
what is the inner core made of?
iron and nickel
Define hot spots:
volcanic regions fed by underlying magma
*independent of plate boundary lines