Large partition coefficients for trace elements in high-silica rhyolites

Geochimica et Cosmochimica Acta
By:  and 

Links

Abstract

The partitioning of 25 trace elements between high-silica rhyolitic glass and unzoned phenocrysts of potassic and sodic sanidine, biotite, augite, ferrohedenbergite, hypersthene, fayalite, titanomagnetite, ilmenite, zircon, and allanite has been determined by INAA on suites of samples from the mildly peralkaline lavas and tuff of the Sierra La Primavera, Mexico, and the metaluminous, compo. sitionally zoned, Bishop Tuff, California. The partition coefficients are much larger than published values for less silicic compositions; the range of values among Primavera samples that differ only slightly in temperature or bulk composition approaches that previously reported from basalts to rhyodacites. Intrinsic temperature dependence of the crystal/liquid partitioning is apparently small. The high values of partition coefficients reflect principally the strongly polymerized nature of the alkali-aluminosilicate liquid, whereas the marked variability of values for partition coefficients is attributed to differences in the concentrations of complexing ligands and/or different degrees of melt polymerization. Great variation in the values of partition coefficients that are potentially applicable to early stages in the partial melting of crustal rocks complicates assessment of

  • 1.

    (1) source regions for granitic melts and

  • 2.

    (2) contributions by crustal-melt increments to andesites.




Publication type Article
Publication Subtype Journal Article
Title Large partition coefficients for trace elements in high-silica rhyolites
Series title Geochimica et Cosmochimica Acta
DOI 10.1016/0016-7037(83)90087-X
Volume 47
Issue 1
Year Published 1983
Language English
Publisher Elsevier
Description 20 p.
First page 11
Last page 30
Google Analytic Metrics Metrics page
Additional publication details