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GEOREF RECORD

Microprobe analyses of plagioclases from metamorphic carbonate rocks of the Central Alps

Eduard Wenk, Hans Schwander and Hans R. Wenk
Microprobe analyses of plagioclases from metamorphic carbonate rocks of the Central Alps
European Journal of Mineralogy (February 1991) 3 (1): 181-191

Abstract

Microprobe analyses of plagioclase in carbonate rocks from the Tertiary metamorphic belt of the Central Alps demonstrate a selective frequency distribution of An-content, with maxima 0-3, 29-39, 65-71, 89-96 and minima 4-22 (peristerite), 47-62 (Boggild), 74-84 (Huttenlocher). Rational microscopic intergrowths of sodic andesine, calcic labradorite and anorthite are observed in the same rocks. These data are significant for the equilibrium phase diagram of the plagioclase series at temperatures of metamorphism which cannot be determined experimentally. The regional distribution of An-groups shows a wide high-grade zone in the centre, with intermediate to very calcic plagioclase, surrounded by a marginal oligoclase-andesine zone without plagioclase An > 50, bordering the pure albite zone of the greenschist facies. Peristerite feldspars are confined to the border greenschist/amphibolite facies. The results of this microprobe study are compared with those obtained by U-stage method. Accuracy and precision of the two methods are discussed.


ISSN: 0935-1221
Serial Title: European Journal of Mineralogy
Serial Volume: 3
Serial Issue: 1
Title: Microprobe analyses of plagioclases from metamorphic carbonate rocks of the Central Alps
Affiliation: Univ. Basel, Mineral.-Petrogr. Inst., Basel, Switzerland
Pages: 181-191
Published: 199102
Text Language: English
Publisher: Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller), Stuttgart, Federal Republic of Germany
References: 21
Accession Number: 1994-052596
Categories: Mineralogy of silicatesIgneous and metamorphic petrology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 1 table, geol. sketch map
N46°00'00" - N47°00'00", E09°00'00" - E11°30'00"
Country of Publication: Germany
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data from Geoline, Bundesanstalt fur Geowissenschaften und Rohstoffe, Hanover, Germany
Update Code: 199424
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