How Peak Oil Affects Agriculture

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Geological Hazards
Plate Tectonics- Theory
Alfred Wegener

Crust- Solid
Mantle- Liquid
Outer Core- Liquid
Inner Core- Solid (Too much pressure for it to be liquid. Doesn’t have the space to expand.)

Convections cells- Due to the pressure in the earth’s core, when it heats up the pressure causes the heat to push against the earth’s mantle, triggering it to move, caused by convection currents.
Convection Currents- it’s a concept of what causes the plate tectonics to move. http://www.scotese.com/pangeanim.htm Plate Boundaries Map

Types of Crust:
Oceanic- young, thin, under oceans, very dense.
Continental- old, thick, makes up land, less dense.
Crusts move towards each other, continental crust is less dense, therefore moves on top of the oceanic crust. The oceanic crust-being closer to the mantle (heat)- burns up through the continental crust, causing volcanoes. A- Diverging plate boundaries- moving apart, it can happen between continental or oceanic crust. The crust moves apart, which forms new oceanic crust, therefore making it young. Volcanoes are formed, but there is no grinding against plates, thus no earthquakes. B- Converging plate margins- earthquakes and volcanoes. The plates coming together. Crusts move towards each other, continental crust is less dense, therefore moves on top of the oceanic crust. The oceanic crust-being closer to the mantle (heat)- burns up through the continental crust, causing volcanoes. East side of south America- trenches. C- Transform Fault Boundaries- Grinding of crust, meaning earthquakes. The longer between earthquakes, the bigger they will be. The San Andreas Fault Line on the Carrizo Plain in Cali.

Subducts- go down.

Are earthquakes and volcanoes located equally and randomly over the earth’s surface? * No, volcanoes and earthquakes are not randomly spread over the earth’s surface as they are linked to plate boundaries. Also, they are mainly around the areas of the coastal regions, as

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