Melt retention and segregation beneath mid-ocean ridges

  title={Melt retention and segregation beneath mid-ocean ridges},
  author={Ulrich H. Faul},
  • U. Faul
  • Published 19 April 2001
  • Geology, Medicine
  • Nature
Geochemical models of melting at mid-ocean ridges—particularly those based on trace elements and uranium-decay-series isotopes—predict that melt segregates from the matrix at very low porosities, of order 0.1%. Some of these models also require that the melt ascends rapidly. But these predictions appear to conflict with seismic data obtained by the mantle electromagnetic and tomography (MELT) experiment. These data reveal, beneath the East Pacific Rise (at 17 °S), a region of low velocities… 
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