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 third layer of the atmosphere, directly above the stratosphere and directly below the thermosphere.
Inner Core
the fourth layer inside the Earth.
Outer Core
is mostly composed of liquid iron and nickel.
Seismic Waves
waves that travel through or over Earth.
Oceanic Crust
The outermost layer of Earth’s lithosphere that is found under the oceans and formed at spreading centers on oceanic ridges.
Continental Crust
continental crust, the outermost layer of Earth’s lithosphere that makes up the planet’s continents and continental shelves
Density
the degree of compactness of a substance.
Alfred Wegener
a German climatologist, geologist, geophysicist, meteorologist, and polar researcher.
Continental Drift
a revolutionary theory explaining that continents shift position on Earth’s surface.
Convergent Boundary
When two plates come together, it is known as a convergent boundary.
Divergent Boundary
A 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
a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity.
Pangaea
a supercontinent that incorporated almost all the landmasses on Earth.
Laurasia
the more northern of two large landmasses that formed part of the Pangaea supercontinent from around 335 to 175 million years ago.
Gondwana
an ancient supercontinent that broke up about 180 million years ago.
Mesosaurus
an extinct genus of reptile from the Early Permian of southern Africa and South America.
Glossopteris
the largest and best-known genus of the extinct Permian order of seed ferns known as Glossopteridales.
