Divergence of plates

Divergence of platesDivergent plate boundaryPlates move apart, creating a zone of tensionOceanicAs plates made of oceanic crust pull apart, a crack in the ocean floor appears. Magma then oozes up from the mantle to fill in the space between the plates, forming a raised ridge called a mid- ocean ridge. The magma also spreads outward, forming new ocean floor and new oceanic crustEffects that are found at a divergent boundary between oceanic plates include: a submarine mountain range such as the Mid-Atlantic Ridge; volcanic activity in the form of fissure eruptions; shallow earthquake activity; creation of new seafloor and a widening ocean basin.

continentalWhen two continental plates diverge, a valley like rift develops. This rift is a dropped zone where the plates a pulling apart. As the crust widens and thins, valleys form in and around the area, and volcanoes become increasingly active.

TheEast Africa Rift Valleyis a classic example of this type of plate boundary. The East Africa Rift is in a very early stage of development. The plate has not been completely rifted and the rift valley is still above sea level but occupied by lakes at several locations. The Red Sea is an example of a more completely developed rift. There the plates have fully separated and the central rift valley has dropped below sea level.7Transform fault boundaryTransform fault boundaryPlates slide or grind past each other without diverging or converging. The relative motion is predominantly horizontal in either sinistral or dextral direction. Transform faults end abruptly and are connected on both ends to other faults, ridges or subduction zones.

The only effect is earthquake. There are no mountains or volcanoes forming from this boundary.

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