essay 2 divergent boundries

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plates move apart driven by convection currents in the mantle. Tensional forces cause fractures in the litosphere and new crust created from magma

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as a result they are called boundaries of construction. The process driving plates apart is called sea floor spreading

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Sea floor spreading is the process where new oceanic crust is formed trough volcanic activity and then gradually moves away from the boundary

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older rocks found further away while newer rock found closer to the spreading zone, the ocean floor near the mar is about 10m old whereas the ocean floor nearer to europe and north america is about 180m old.It was proposed by harry h hess in 1960

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Sfs has built the 50,000 km long system of mid oceanic ridges.mor is an underwater mountain range making the mor the longest mountain range in the world

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The playtes carrying eurasiam, na ,south america and africa split along the mar over 100m ago moving at a rate of no faster than 2.5cm per year

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the mar extends from the north pole to the south pole and reaches 3000m above the ocean floor in places.It comes to the surface forming islands e,g iceland and the azores

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Iceland which sits on the mar is splitting long the spreading centre the gap between the 2 plates will become wider until it is filled by sea water forming 2 islands

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if a diverging plate boundary lies under a continental plate e.g Africa a rift valley will form formation of a rift valley is called rifting.formed when 2 plates pull apart or when 1 plate is trying to pull itself apart and the newly created rock are strectched until they break and drop down

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theres a rift valley on the east side of africa called the ear, cracks on the sea floor are being filled by magma which cools when meeting sea forms basalt new ocean floor

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somalian and nubian plates are pulling away fro the arabian plate

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divergence causing east africa to split f from the rest of africa forming the red sea and gulf of eden

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black cmokers sometimes occur at mid oceanic ridges.They are chimney like vents which emit hot water and gases which setlle on the ocean floor to form mineral ores

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proofs for divergence are deposits of glacial material simlar age are found where continents were once attatched,ocean floors further away from divergence are thicker than floor closer