plate tectonics Flashcards
lithosphere
the rigid outer part of the earth, consisting of the crust and upper mantle.
Asthenosphere
the upper layer of the earth’s mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur.
Mesosphere
the region of the earth’s atmosphere above the stratosphere and below the thermosphere
Inner Core
innermost part of Earth is the core and is about 1500 miles
Outer Core
liquid, iron-nickel layer of the Earth between the solid inner core and lower mantle
Seismic Waves
lastic wave in the earth produced by an earthquake or other means
. Oceanic Crust
relatively thin part of the earth’s crust which underlies the ocean basins. It is geologically young compared with the continental crust and consists of basaltic rock overlain by sediments
Continental Crust
relatively thick part of the earth’s crust that forms the large landmasses. It is generally older and more complex than the oceanic crust.
Density`
mass of a unit volume of a material substance.
Alfred Wegener
continental landmasses were “drifting” across the Earth, sometimes plowing through oceans and into each other.
Continental Drift
gradual movement of the continents across the earth’s surface through geological time.
Convergent Boundary
impact of the colliding plates can cause the edges of one or both plates to buckle up into a mountain ranges or one of the plates may bend down into a deep seafloor trench
Divergent Boundary
occurs when two tectonic plates move away from each other.
Transform Boundary
places where plates slide sideways past each other
Sea-floor Spreading
formation of new areas of oceanic crust, which occurs through the upwelling of magma at midocean ridges and its subsequent outward movement on either side.
