Jihgh

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  • Topic: Plate tectonics, Seafloor spreading, Mid-ocean ridge
  • Pages : 2 (350 words )
  • Download(s) : 41
  • Published : December 3, 2012
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Divergent boundaries are locations where plates are moving away from each other. This occurs above rising convection currents. The rising current pushes up on the bottom of the lithosphere lifting it and flowing it literally beneath it

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What are divergent boundaries

What is divergent boundaries These boundaries occur when spreading centers where plates are moving apart and new crust is created by magma pushing up from the mantle picture two giant conveyor belts facing each other but slowly moving in opposite directions as they transport newly formed oceanic crust away from the ridge crest

What does lithosphere do in this

When a divergent boundary occurs beneath oceanic lithosphere, the rising convection current below lifts the lithosphere producing a mid-ocean ridge. Extensional forces stretch the lithosphere and produce a deep fissure. When the fissure opens, pressure is reduced on the super-heated mantle material below. It responds by melting and the new magma flows into the fissure. The magma then solidifies and the process repeats itself

. how do they form A divergent plate boundary is formed where tensional tectonic forces result in the crustal rocks being stretched and finally split apart, or rifted. The central block drops to form a graben, and basaltic volcanism is abun dant along the rift's faults. The rise of hot mantle material beneath the rift zone pushes the rift valley farther apart . Today's active divergent boundaries are mid oceanic ridges (sea floor spreading centers). Divergent boundaries can also develop on land, as did those that broke up Pangaea about 200 million years ago. Continental rifting can end before the crustal mass has been fully separated. These failed rifts then become seas or large basins...
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