In this lecture you will:
|Earthquakes were used to determine the
layers by REFRACTION due to DENSITY
-- seismic waves generated during earthquakes provide info about the interior of the earth
– they reflect and change direction at boundaries between layers (like light changes direction in glass)
-- some regions don't carry waves because
they are liquid.
inner .... almost pure iron. .. solid due
How the earths core acts as magnet. Not
as simple as "its iron"
-- the upper part of the mantle is composed
of viscoelastic material. It acts like a solid when hit with
seismic waves, but it will flow under forces maintained for a long
-- thin – about 5 miles under the oceans
and 10 to 30 miles under the continents.
Why does the crust of Earth "ride" or
float on top of the mantle?
Which part of the Earth's structure
is responsible for its
Which part of the Earth's structure is essential for plate
tectonics to occur? Why do the plates move?
Is the crust the same depth everywhere