Melt retention and segregation beneath mid-ocean ridges

@article{Faul2001MeltRA,
  title={Melt retention and segregation beneath mid-ocean ridges},
  author={Ulrich H. Faul},
  journal={Nature},
  year={2001},
  volume={410},
  pages={920-923}
}
  • 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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We review physical and chemical constraints on the mechanisms of melt extraction from the mantle beneath mid–ocean ridges. Compositional constraints from MORB and abyssal peridotite are summarized,
Investigating solid mantle upwelling rates beneath mid-ocean ridges using U-series disequilibria, 1: a global approach
Abstract U-series disequilibria in MORB produce trends of ( 230 Th)/( 232 Th) as a function of ( 238 U)/( 232 Th) for given lengths of ridge often defined by first-order segmentation. These trends
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Abstract Geochemical observations of MORB including U-series disequilibria are used to examine the processes and timescales of MORB melt generation. Incompatible elements in MORB suggest that the
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