Chapter 25.3 and 25.4 Flashcards
What is the boundary that marks density change between layers?
Discontinuity
How can discontinuities be identified?
Seismic waves
What are Shadow Zones?
The areas where no seismic waves are recorded
What is another term for Shadow Zone?
Dead Zone
Between which two degrees do shadow zones fall in?
105 and 140 degrees
Is the outer core a solid or a liquid?
Liquid
Is the inner core a solid or liquid ? Why?
The inner core is solid because of the pressure
What makes up the lithosphere ?
The crust and the uppermost mantle
What is the asthenosphere?
A weak, plastic like layer which earth’s plates move on
Which elements make up the mantle?
Calcium, aluminum, iron, and Magnesium
What 2 elements make up the core?
iron and nickel
is the measure of fluid’s resistance to flow
Viscosity
A chemical compound silicon dioxide, which is a common ingredient in most magma
Silica
Is small, have heights in the hundreds of meters range, and have short eruption cycles
Cinder cone volcanoes
A broad, flat structures composed layer upon layer of lava flows
Shield volcanoes
A large and steep-sided , often thousands of meters high and tens of kilometers across the base, composed of lava and ash
Composite Volcanoes
What is molten , or liquid, rocks stored inside Earth is called?
Magma
Where is the ring of fire located?
The Pacific Ocean
What are two specific example of volcanic activity due to divergents?
East African Rift Valley
MId Atlantic RIdge
Are hot spots stationary ?
Yes hot stops are stationary only the plate above moves
What is created from hot spots?
Islands
If it liquid has a high viscosity will it flow more quickly or more slowly?
It will flow more slowly
If magma has high viscosity will it contain more or less silica ?
It will contain more silica
What is Pyroclastic Material?
any solid material that erupts from a volcano
