Hostname: page-component-848d4c4894-xfwgj Total loading time: 0 Render date: 2024-06-21T14:38:38.655Z Has data issue: false hasContentIssue false

Petrologic evidence for a rhodochrosite precursor of spessartine in coticules of the Venn-Stavelot Massif, Belgium

Published online by Cambridge University Press:  05 July 2018

W. Schreyer
Affiliation:
Institut für Mineralogie, Ruhr-Universität Bochum, Germany
H.-J. Bernhardt
Affiliation:
Institut für Mineralogie, Ruhr-Universität Bochum, Germany
O. Medenbach
Affiliation:
Institut für Mineralogie, Ruhr-Universität Bochum, Germany

Abstract

Minute CaMg-bearing rhodochrosite inclusions were discovered in spessartine crystals of small coticule globules enclosed within redschists that form the country rock of the famous coticule bands of Belgium. This points to a former metamorphic reaction relationship between the two minerals, such as rhodochrosite + pyrophyllite = spessartine + quartz + CO2 + H2O. The coexistence of spessartine with Mg-chlorite in the coticule globule could also indicate more complex reactions such as rhodochrosite + sudoite + quartz = spessartine + Mg-chlorite + CO2 + H2O. Our finding casts some doubt on the suggestion by Kramm (1976) that spessartine formed from Mn-montmorillonite in previously glassy volcanic tufts.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Chatterjee, N. D. and Flux, S. (1986) Thermodynamic mixing properties of muscovite-paragonitc crystalline solutions at high temperatures and pressures, and their geological applications. J. Petrol., 27, 677–93.CrossRefGoogle Scholar
De Dycker, R. (1939) Recherches sur la nature et les causes du mrtamorphisme des terrains manganésiféres du Cambrien suprrieur, dans la pattie Sud-Occidentale du massif de Stavelot. Ann. Soc. Geol. Belg., 62, M1-106.Google Scholar
Fransolet, A.-M. (1972) Donnéess nouvelles sur la carpholite de Meuville. Bull. Soc. fr. Minéral. Cristal-logr., 95, 8497.Google Scholar
Fransolet, A.-M. and Bourguignon, P. (1978) Di/trioctahedral chlorite in quartz veins from the Ardenne, Belgium. Can. Mineral., 16, 365–73.Google Scholar
Fransolet, A.-M. and Kramm, U. (1983) Mineralogie und Petrologie Mn-reicher Metapelite des Venn-Stavelot Massivs, Ardennen, und die varistische Metamorphose im nordwestlichen Rheinischen Schild. Fortschr. Mineral., 61, 3169.Google Scholar
Fransolet, A.-M. and Schreyer, W. (]977) Metamorphose und Magmatismus im Venn-Stavelot-Massiv, Ardennen. Ibid., 55, 75103.Google Scholar
Fransolet, A.-M. Abraham, K., and Sahl, K. (1984) Davreuxite: a reinvestigation. Am. Mineral., 69, 777–82.Google Scholar
Halbach, H. and Chatterjee, N. D. (1982) The use of linear parametric programming for determining internally consistent thermodynamic data for minerals. In High-pressure researches in geoscience (W. Schreyer, ed.) E. Schweizerbart'sche Verlagsbuchhandlung Stuttgart, pp. 475-91.Google Scholar
Hsu, L. C. (1968) Selected phase relationships in the system AI-Mn-Fe-Si-O-H: A model for garnet equilibria. J. Petrol., 9, 4083.CrossRefGoogle Scholar
Kramm, U. (1976) The coticule rocks (spessartine quartzites) of the Venn-Stavelot Massif, Ardennes, a volcanoclastic metasediment? Contrib. Mineral. Petrol., 56, 135–55.CrossRefGoogle Scholar
Kramm, U. (1980) Sudoite in low-grade metamorphic man ganese rich assemblages. Neues Jahrb. Mineral., Abh., 138, 113.Google Scholar
Krosse, S. (1983) Rotschiefer und Coticules der Ardennen (Belgien). Unpublished Diploma Thesis, Ruhr-Universitáit Bochum, 101 pp.Google Scholar
Lamens, J. and Geukens, F. (1984) Volcanic activity in the Lower Ordovician of the Stavelot Massif, Belgium. Med. Kon. Acad. Wet. Brussels, 46, 113.Google Scholar
Lamens, J. and Geukens, F. and Viaene, W. (1986) Geological setting and genesis of coticules (spessartine metapelites) in the Lower Ordovician of the Stavelot Massif, Belgium. J. Geol. Soc. London, 143, 253–8.CrossRefGoogle Scholar
Lessuise, A. (1981) Le Coticule. Ann. Mines Belgique, 1981, fasc. 2, 101-25.Google Scholar
Medenbach, O. (1985) A new microrefractomreter spindle-stage and its application. Fortschr. Mineral., 63, 111–33.Google Scholar
Renard, A. (1878) Sur la structure et la composition minéralogique du coticule et sur ses rapports avec le phyllade oligistif6re. M(m. Cour. Acad. roy. Belgique, 41, 142.Google Scholar
Schreyer, W. (1975) New petrologic evidence for Hercynian metamorphism in the Venn-Stavelot Massif, Belgium. Geol. Rundschau, 64, 819–30.CrossRefGoogle Scholar
Schreyer, W. Fransolet, A.-M., and Abraham, K. (1986) A miscibility gap in the trioctahedral Mn-Mg-Fe chlor-ites: Evidence from the Lienne Valley manganese deposit, Ardennes, Belgium. Contrib., Mineral. Petrol., 94, 333–42.CrossRefGoogle Scholar
Spry, P. G. (1990) Geochemistry and origin of coticules (spessartine-quartz rocks) associated with metamorphose massive sulfide deposits. In Regional metamorphism of ore deposits and genetic implications (Spry and Bryndzia, eds) VSP Utrecht, p. 49-75.Google Scholar