Contributions to Mineralogy and Petrology

, Volume 74, Issue 1, pp 7–12 | Cite as

Melt density and the average composition of basalt

  • Edward Stolper
  • David Walker
Article

Abstract

Densities of residual liquids produced by low pressure fractionation of olivine-rich melts pass through a minimum when pyroxene and plagioclase joint the crystallization sequence. The observation that erupted basalt compositions cluster around the degree of fractionation from picritic liquids corresponding to the density minimum in the liquid line of descent may thus suggest that the earth's crust imposes a density filter on the liquids that pass through it, favoring the eruption of the light liquids at the density minimum over the eruption of denser more fractionated and less fractionated liquids.

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Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • Edward Stolper
    • 1
  • David Walker
    • 2
    • 3
  1. 1.Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaUSA
  2. 2.Department of Geological SciencesHarvard UniversityCambridgeUSA
  3. 3.Lunar and Planetary InstituteHoustonUSA

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