Plate Tectonics is the theory that the earth's plates are slow constant motion. Each plate moves 7 - 11 cm per year (~3-4 inches) a year because of convection currents in the Earth's Upper Mantle. There are 3 different ways that plates move, which are called "Plate Boundaries." In total, there are 6 type of plate boundaries, including different oceanic and continental boundaries. Oceanic plates are made out of basalt, which is less dense than continental plates, which are made of granite.
Convergent Boundary
Convergent boundaries are when two plates move toward each other and collide. When this happens, result vary for what two plates are converging. If the plates are continental plates, volcanic mountains form along the boundary, bringing magma up from the Upper mantle. If the two plates are ocean plates, then they result in subduction zones. If oceanic and continental crust collide, the result is a deep ocean trench.
|
|
Divergent Boundaries
![Picture](/uploads/9/6/8/0/96804018/published/continental-continental-constructive-plate-boundary-svg.png?1484673378)
Divergent boundaries are when two plates move away from each other. Like convergent boundaries, different things form when boundaries are oceanic or continental. When Oceanic plates diverge with oceanic plates, they form mid ocean ridges. When Continental diverges with Continental, it forms rift valleys. However, we know nothing forms when oceanic and continental diverge, yet.
Transform Bondaries
Transform boundaries are very simple, two plate slide past each other in opposite directions. Nothing else doesn't form depending on what the plates are, they always results in earthquakes. They are also known as "Transform Faults." That's what we know.