2: plate tectonics Flashcards
who outlined the continental drift hypothesis and supercontinent (Pangea) theory?
Alfred wegener
what idea did the continental drift challenge?
that the earth’s continents and ocean basins had fixed geographic positions
oceanic crust is composed of
basaltic rock
continental crust is composed of
granitic rock
what does asthenos mean in asthenosphere
weak
what does lithos mean in lithosphere
stone
the plates of the earth are apart of the
lithosphere
the longest topographic feature on earth is
the global oceanic ridge system
convergent boundaries are also called
subduction zones
deep ocean trenches are produced from
convergent boundaries/subduction zones
what is a mantle plume
a cylindrical upwelling of hot rock originating from the mantle
how did we confirm the ocean floor’s youngest at the ridge axis?
deep sea drilling
what is a hot spot
an area of volcanism, high heat flow, crustal uplift measuring some kilos across
what are hot spots general position
relatively fixed within the mantle
if a plate moves over a hot spot, what is created?
a hot spot track
