Tectonic Hazards Flashcards
describe the earths structure
core- hot and under a lot of pressure
inner core - solid
outer core - liquid
mantle surrounds core solid that can flow
crust thin layer compared to mantle and core
name 2 types of crust
continental and oceanic
how do continental and oceanic crusts differ (3)
they have different chemical composition, thickness and density
what do the crust and upper mantle form together
a shell at earths surface called lithosphere
describe the lithosphere
it is broken into fragments called tectonic plates -
where do 2 tectonic plates meet
at a plate margin
what do the 3 types of plate margin tell us
they describe how the plates move
name 3 types of plate margins
constructive
destructive
and conservative plate margins
what is the cause of an earth quake
the interaction between the tectonic plates and the mantle beneath
how do we know that tectonic plates move
evidence by gps measurements over time
what are the 3 theories for what makes tectonic plates move
convection
ridge push
slab pull
describe the convention theory for the movement of tectonic plates
the cores temperature causes magma to rise in the mantle and sink in the core
when it cools currents flow in the lithosphere building up pressure
and carrying the plates
describe the ridge push theory for the movement of tectonic plates
at constructive margin ocean ridge form above ocean floor
beneath the ridge the mantle melts
molten magma rises as the plates move apart and cool down to form new plate material
as lithosphere cools it becomes dense and starts to slide down away from ridge causing plates to move away from each other
describe the slab pull theory for the movement of tectonic plates
at destructive margin denser plates sink back into mantle and the rest of the plate is pulled along behind it
where are volcanoes found
on land and sea at constructive and destructive plate margins are located
