What+we+learned+from+the+geologic+tutorial.



crust- outermost & thinnest layer (20 miles thick) mantle- upper and lower regions, hot semi-solid rock (1800 miles thick) outer core- liquid layer (1400 miles thick) inner core- solid because of pressure, extremely hot, (750 miles diameter) lithosphere- extends into the mantle from the crust asthenosphere- viscous

Plate tectonics theory- plates slowly but constantly move around the planet. (Theory by Alfred Wegener) Plate tectonics cause earthquakes, volcanoes, and other geologic events Convergent boundaries- 2 plates pushing toward each other Divergent boundaries- 2 plates moving apart from each other Transform boundaries- 2 plates slide past each other

How does thermal energy make plates move?Convection occurs in the liquid of the mantle causing the plates to move because the plates are resting on the solid part of the mantle that floats.

Geologic disaster examples: volcanic eruptions, earthquakes, tsunamis, and more

At some convergent boundaries oceanic plates collide with a continental plate. Oceanic plates are denser and thinner so it goes under the continental crust. This is a subduction zone. media type="youtube" key="ep2_axAA9Mw" height="390" width="480"

2 continental plates colliding can form mountains by piling up the broken pieces after colliding.

Seafloor spreading- magma will ooze out of the crack and reform the ocean floor/crust Rift = a dropped zone. water will rush into the rift and form new ocean basin Mid-ocean ridges occur when plates spread apart

Earthquakes occur when plates grind together because they have rough edges

North American & Caribbean plate boundary- transform boundary Philippine & Pacific plate boundary- convergent boundary Iceland plate boundary- divergent boundary

The lithosphere is broken into several large tectonic plates San Andreas fault= strike-slip fault Island arcs created by collision of 2 oceanic plates Pangea began to break up 200 million years ago

[|Worlds Tectonicplates]