ISSN:
1432-0967
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract Primary melt and coexisting mineral compositions, at increasing degrees of partial melting at 15 kbar, were determined for an iron-rich martian mantle composition, DW. The composition of primary melts near the solidus was determined with basalt-peridotite sandwich experiments. In order to evaluate the approach of the liquids to equilibrium with a DW mantle assemblage, experiments were also performed to establish the liquidus mineralogy of the primary melts. Primary melt compositions produced from an iron-rich mantle are more picritic than those produced from an iron-poor mantle. By increasing the iron content of a model mantle composition (decreasing the mg#, where mg# = atomic [Mg/(Mg+Fe2+)*100]), picritic and komatiitic magmas result at lower percentages of melting and at temperatures closer to the solidus than in an iron-poor mantle. Terrestrial iron-rich primitive volcanics may be the partial melting products of iron-rich, mg# ≥80, source regions. The DW partial melting results support the conclusion of previous authors that the parent magmas of the SNC (shergottites, nakhlites, chassignites) meteorites were derived from a source region that had been previously depleted in an aluminous phase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00310771
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