volcanlo and plate techtonics Flashcards
(24 cards)
what comprises the lithosphere?
crust and upper most solid mantle.
what are the 3 main layers of the earth.
crust mantle and core
what is the theory of continental drift
that the continents used to be one big continent which slowly pulled apart
who came up wit he theory of continental drift
Alfred wegener
why was the theory of continental drift discarded?
there was no way to explain HOW the continents could move
what is the definition of geology
study of earth’s composition, structure and history
what is pangae
a supercontinent before continental drift
what happens at mid ocean ridges
new ocean crust forms
how do transform boundaries move
against
how do converging boundaries move
towards
how do diverging boundaries move
away
what are volcano explosions type determined by?
magma
what is a composite (stratovolcanoes)
explosive eruptions of lava and ash
what is a cinder cone volcano
steep sided volcano formed of ash and cinders
what is a batholith
largest intrusive igneous
what is a caldera
when the top of a volcano collapses and fills with water
what is a normal fault
when the hanging wall drops
reverse (thrust) fault
when the hanging wall goes up
strike-slip fault
when they move apart
sea floor spreading evidence
radioactive dating of rocks, magnetic reversals of the iron core, continental puzzles
which wave travels faster. P or S?
p
what do p waves travel through
liquids
how do S waves travel
up and down
what do S waves travel through
solid
