chapter 25.3-25.4 Flashcards
What is the boundary that marks a density change between layers?
discontinuity
How can discontinuities be identified?
Seismic waves.
What are shadow zones?
Areas on Earth where no Seismic waves are recorded.
What is another term for a shadow zone?
A dead zone.
Between which two degrees do shadow zones fall under?
Between 105 and 140 degrees.
Is the outer core a solid or a liquid?
Liquid.
Is the inner core a solid or liquid?
A solid because of the pressure.
What makes up the lithosphere?
The crust and the uppermost mantle.
What is the asthenosphere?
Plastic like layer which Earths plates move on.
Which elements make up the mantle?
Calcium, aluminum, iron, and magnesium.
Which elements make up the core?
Metallic materials such as nickel and iron.
The measure of a fluid’s resistance to flow.
Viscosity.
the chemical compound silicon dioxide, SiO2, which is a common ingredient in most magma.
Silica.
Tend to be small, have heights in the hundreds of meters range, and have short eruption cycles.
Cinder cone volcanoes.
Broad, flat structures composed of layer upon layer of lava flows.
Shield volcanoes.
large and steep-sided, often thousands of meters high and tens of kilometres across the base, and composed of thousands of layers of both lava and ash.
Composite volcanoes.
What is molten or liquid rocks stored inside earth called?
Magma
Where is the ring of fire located?
The Pacific ocean.
What is created when tectonic plates collide along subduction zones?
Volcanoes.
What are two specific examples of volcanic activity due to divergence?
Mid-Atlantic ridge and East African rift.
Are hot spots stationary?
Yes.
What is created from hot spots?
islands (Hawaiian islands)
If a liquid has a higher viscosity will it flow more quickly or more slowly?
More slowly.
If magma has high viscosity will it contain more or less silica?
More.
What is pyroclastic material?
Any solid material that erupts from a volcano.
What is the smallest type of pyroclastic material?
volcanic ash.
what are the largest types of pyroclastic material?
Volcanic blocks and bombs.
what are the types of gases that erupt from volcanoes?
water vapor, carbon dioxide, and sulfur dioxide.
How are volcanoes classified?
Size, shape, and materials erupted.
What are the three types of volcanoes?
CInder Cone, shield, and composite volcanoes.
