Abstract

New hornblende/groundmass partition coefficients for rare earths in a sodic, high-Al2 O3 dacite range from 0.9 for Ce to 4.5 to 6.2 for heavy rare earths, and the pattern is concave down with a distinct negative Eu anomaly. These coefficients indicate that hornblende may have been an important residual phase in the generation of high-Al2 O3, heavy-rare-earth-depleted trondhjemites, tonalites, and equivalent dacites, implying that the magmas formed at a depth of less than 60 k.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.