Phase relations of pumpellyite-actinolite facies metabasites in the Sanbagawa metamorphic belt in central Shikoku, Japan

31Citations
Citations of this article
7Readers
Mendeley users who have this article in their library.
Get full text

Abstract

Sanbagawa metabasites metamorphosed at conditions near the upper limit of the pumpellytic-actinolite facies were examined in terms of phase equilibria in the five component system Al2O3Fe2O3CaOMgOFeO. The Fe3+ content of epidote measured as XEpFe (=Fe/(Fe + Al) of epidote) in the assemblage epidote-chlorite-actinolite-pumpellyite decreases gradually towards the higher-grade, pumpellyite-free areas. The progressive change in XFeEp can be detected within one metabasite bed 200 meters thick near the upper limit of the pumpellyite-actinolite facies. The MgFe2+ substitution, as expressed by variation of Fe/(Fe + Mg) in chlorite (0.40-0.55) has little effect on the Fe3+ + Al) ratios of epidote and pumpellyite in the above-mentioned assemblage. The lowet XFeEp in the pumpellite-bearing assemblage is 0.15 and hence the upper limit of the pumpellyite-actinolite facies is defined by the appearance of an epidote-chlorite-actinolite assemblage with XEpFc = C.15. © 1982.

Cite

CITATION STYLE

APA

Nakajima, T. (1982). Phase relations of pumpellyite-actinolite facies metabasites in the Sanbagawa metamorphic belt in central Shikoku, Japan. LITHOS, 15(4), 267–280. https://doi.org/10.1016/0024-4937(82)90018-4

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free