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Well, today in class we did notes on the theory of plate tectonics. The first thing we talked about was continental drift. This is large-scale movements of the continents over the globe. The first scientist to come up with this theory was Alfred Wegener in 1915, but no one really beleived him. No one really believed this theory until the 1980's actually. People started believing this theory once the evidence for continental drift was proven. There are five peices of evidence. 1) Continents fit together like a puzzle. 2) They all have similar gelogical features. 3) Similar fossil records. 4) Volcanoes and earthquakes follow ridge lines. 5) Monitoring distance between continents- seafloor spreading. Then we talked about the seafloor spreading. This explains why the plates move apart from the rocks and cracks form and magma rises through the cracks and cools on the ocean floor forming oceanic crust and oceanic ridges. Then we talked about the three different types of plate boundaries. There are: 1) Divergent 2) Convergent (subduction and collision) 3) Transform. Now, to start with convergent plate boundaries. One type is Colliding Plates. This happens when a continental plate and a continental plate collide. The crust is so thick that material gets pushed up and it forms mountains like the mountains we hike on. The second time is Subduction. This happens when one plate goes underneath another plate. This forms volcanoes. When it is oceanic to oceanic subduction this forms volcanic islands and trenches on the ocean floor. Then we talked about divergent plate boundaries. This happens when plates move away from one aother. This alsmot always happens with oceanic plates only. This is when the plates move away frm one another and create oceanic mountains and oceanic ridges. Lastly, we talked about transform plate boundaries. This happens when plates grind on each other. This creates a falt line beaucse plates are grinding on each other and this creates earthquakes. Well, that's aabout all for today.

Tomorows scribe will be will have fun!