Unformatted text preview: eeted dikes.
Sediments are deposited on the spreading seafloor. The gabbro layer metamorphoses by contact with the magma. Peridotite layer Mantle Dikes intruding dikes Spreading
minerals Magma chamber
Peridotite layer Decompression
Melting Mantle The heated seawater then rises. Dissolved minerals precipitate in the ocean. Crystals settle out of the magma, forming the peridotite layer. Fluid Induced
Melting Magma of intermediate composition is erupted to form arc volcanoes. Molten sediments combine with lithospheric magma. Trench
Oceanic sediments Magma chamber Oceanic crust basalt
lithosphere The water
and molten sediments melt parts of the overlying plate. Asthenosphere Subducting oceanic crust carries sediments with it.
H2O Water remains trapped
as the pressure and temperature inc...
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- Summer '08
- Igneous rocks, Basalt