plate tectonics
Braden Schuster
The start of plate tectonics.
Alfred Wegener was the first to discover plate tectonics. He found that two continents could fit together(Africa and South America). Most scientists disagreed with this theory because they thought it isn't possible. Some people did support it. Alexander du Toit and Arthur Holmes did support him.
plate boundaries
The plate boundaries are convergent , divergent , and transform. Convergent boundaries are when two plates overlap. divergent boundaries are when two plates spread and form new crust. Transform boundaries are when two plates slide against each other. Lots of things form from plate boundaries such as mountains.The movement between them can cause earthquakes. Asia has all three plate boundaries in it.
Plate tectonics cause ocean trenches by converging. Rocks off the east coast of north america are about 1000 years old. The rocks on the mid atlantic ridge are 200 million years old. I think its like this because the continents were in the mid atlantic ridge more than they were off the east coast.
events
A convection current is heat rising and lowering constantly.7 major plate boundaries are Eurasian, north American, south American, Pacific, Australian, Antarctic, and African.Two bad things are volcanoes and earthquakes.These things are caused by the plate boundaries moving. There are good things plate tectonics give us. The weathering of chemicals, breaking down soils, and gives us fossil fuels.Plates do this by making things rise up or break them down.
http://www.cotf.edu/ete/modules/msese/earthsysflr/plates3.html http://en.m.wikipedia.org/wiki/Convergent_boundary http://www.cotf.edu/ete/modules/msese/earthsysflr/plates3.html https://m1keytpt.wordpress.com/2014/05/28/transform-boundaries-2/