California's Major Geological Features

The San Andreas Faults was caused by an earthquakes is San Francisco in 1960. Lassen Volcanic park , it is formed by Mount. Tehama a which was a larger mountain. It eventually collasped and created Lassen volcanic parts. The Sierra Nevada was formed the crust decended into the mantle and the range popped up.

Plate Tectonics

The theory of Plate Tectonics is that the plates are drifting carrying continents with them. Also that the plates often break apart, they also collide creating mountains . This theory also proposes that the Earth's most outer layer, is broken up into 7 different plates: the North American, South American, Eurasian, Australian, Antarctic, and the Pacific plate. These plates are moving about 2 cm to 10 cm a year. The lithospheric plates moves due to the convection currents occuring in the mantle. Earthquakes are also caused by sudden movements of plates rubbing into each other.

Divergent Boundaries

Divergent Boundaries is when two plates move apart from each other. Convection currents cause it to move. The currents pushes the lithosphere casing it to move. The plates then break apart and move away. In the ocean, when a divergent boundary occurs, it creates mid-ocean ridges. When a divergent boundary occurs on the continental plate, the plates rip apart causing faults. During this process, many earthquakes occur.

Mid- Ocean Ridge

A Mid-Ocean ridge is an underwater mountain range, mainly having a valley know as a rift running along its spine, formed by plate tectonics. This type of ocean ridge is a characteristic of what is know as an ocean spreading center, which is responsible for seafloor spreading. The uplifted sea floor results from convection currents which rises in the mantle as magma at a linear weakness in the ocean crust, and emerge as lava,creating new crust upon cooling.A mid-ocean ridge demarcates the boundary between two tectonic plates, and consequently is termed a divergent plate boundary.

Ring of Fire

The Ring of Fire is an area of common earthquakes and volcanic activites. 90% of the world's earth quakes occur there. 81% of the world's biggest earthquakes also occur there. A part of the Pacific Plate and the Juan de Fuca Plate is being subducted beneath the North American Plate. The Ring of Fire has about 452 volcaneos and it includes about 75% of the worlds active and dormant volcanoes. The Ring of Fire is the consequnce of plate tectonics and the movement and the movement of crustal plates.

Covergent Boundaries

The convergent boundaries is where plates crash together. For example, the Oceanic plates may collide with the Continental plate. The oceanic plates gets pushed down to the mantel. This process is know as subduction. The plate then enters a high temepeture envioroment when the plate reaches about 100miles, it begins to melt. The continental plate then creates a volcano. During this process, many earthquakes occur.

Pangea

Pangea, believed to be a super continent, was formed by all the continents. Scientist believe that the east of South America fit into the west of Africa just like a jigsaw puzzle. Sea floor spreading caused Pangea to break apart. The continents then drifted away. Fossils of the same kind were found on different continents. In the early 1900's, Alfred Wegener proposed the idea of Continental Drift. He thought, this idea was the thought of continents moving. Pangea was thought to be formed by the fragments of another supercontinect, Rhodinia. After Rhodinia drifted apart, the continents eventually started drifting together again during the Paleozoic period.