Plate Tectonic Boundaries

king0fknowlage's version from 2017-01-05 15:54


Question Answer
What is a tectonic plate?Pieces of Earth's crust & uppermost mantle referred to as the "LITHOSPHERE"
How do plates move?Plates move due to convection currents (intense heat from the Earth's core that causes molten rock in the mantle layer to move.)
How do we know that plates are currently moving?EARTHQUAKES: Can only happen when two plates slide against each other creating faults
What is Pangaea?A super continent
Divergent Boundary Plates are moving away from each other--Creating Rifts/Ridges--New plates could form, new oceans, volcanoes and sea floor spreading
Convergent (convergent)2 continental plates crashing together---Mountains/Mountain ranges or volcanoes can form
Convergent (Subduction)The oceanic plates are denser and therefore slide under the much lighter/thinner continental plates--Trench, Valley
Transform BoundaryWhen two plates slide against each other HORIZONTALLY--- Faults (a crack in the earth's surface AKA...Earthquakes)
Theory of Continental DriftA theory by the German Scientist ALFRED WAGNER stating that 300mya all of the Earth's land masses were in constant motion, collided to form one super continent called PANGAEA. About 200mya Pangaea Broke apart and the continents drifter apart to their current locations. According to his theory only the continents drifted apart. EVIDENCE: JIGSAW BETWEEN SOUTH AMERICA & AFRICA........FOSSILS OF THE SAME PLANTS AND ANIMALS IN BOTH CONTINENTS..........SIMILAR MOUNTAINS IN AGE AND STRUCTURE ON BOTH SIDES OF THE ATLANTIC OCEAN........SIMILAR ICE SHEETS COVERED PARTS OF SOUTH AFRICA, INDIA, AUSTRALIA, & SOUTHERN AMERICAN ABOUT 250mya.
Theory of Plate TectonicsA theory by J.Tuzo Wilson that the Earth's outer shell is made up of 20 plates. Most of them are made up of both continental & oceanic crust. They are floating on a layer of hot rock. It's likely that convection currents (circular movement in a gas or liquid created by uneven heating) cause by the unequal distribution of heat within the Earth's core cause the plates to move.
What causes Earth quakes and Volcanoes?Both occur along the edge of a plate. During Earthquakes, faults or giant cracks are produced by the pressure of the plates sliding past each other (TRANSFORM), or when they're moving towards each other at
convergent boundaries and one plate is forced below another plate (SUBDUCTION)