Eclogite with unusual atoll garnet from the southern Armorican Massif, France: Pressure-temperature path and geodynamic implications

Cryptonella? cailliaudi Barrois, 1889, from the Lower Devonian of the Armorican Massif, is tentatively assigned to the athyridid brachiopod genus Planalvus Carter, thus far known only from the Lower Carboniferous of eastern North America. In addition, a new species, Planalvus rufus, is described from the Bois-Roux Formation (Pragian) of Brittany, France. These French species are small brachiopods with complex spiralial and jugal structures, which permit assignment to the order Athyridida.

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Palaeozoic history of the Armorican Massif: Models for the tectonic evolution of the suture zones

Comptes Rendus Geoscience ◽

10.1016/j.crte.2008.11.009 ◽

2009 ◽

Vol 341 (2-3) ◽

pp. 174-201 ◽

Cited By ~ 167

Author(s):

Michel Ballèvre ◽

Valérie Bosse ◽

Céline Ducassou ◽

Pavel Pitra

Keyword(s):

Tectonic Evolution ◽

History Of ◽

Armorican Massif

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Fingerprinting the provenance of building stones: a case study on the Louvigné and Lanhélin granitic rocks (Armorican massif, France)

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.185.1.13 ◽

2014 ◽

Vol 185 (1) ◽

pp. 13-31 ◽

Cited By ~ 1

Author(s):

Claudine Malfilatre ◽

Erwan Hallot ◽

Philippe Boulvais ◽

Marc Poujol ◽

Annick Chauvin ◽

...

Keyword(s):

Building Stone ◽

Granitic Rocks ◽

Magnetic Characteristics ◽

Building Stones ◽

Intrinsic Variability ◽

Geological Unit ◽

Qualitative Variables ◽

Identity Cards ◽

Armorican Massif

Abstract Two examples of granitic stones from Brittany (western France) commercialized under the names of “gris-bleu de Louvigné” and “bleu de Lanhélin” were characterized in order to explore how the provenance of a building stone can be traced back with a maximum of confidence. For this purpose, petrographical, geochemical and magnetic characteristics, representing more than 70 quantitative and qualitative variables, were compiled for a total of 32 samples. We have defined two reference populations for these building stones and have extracted their discriminative characteristics. We have then compared four randomly selected samples and two foreign commercial counterparts of these stones to the reference populations. Discriminative variables differ from one case of comparison to the other, which indicates that a combination of various tools and variables will be generally required to unequivocally fingerprint the origin of a given granitic stone. Where several quarries are mining a single geological unit within a composite intrusion, the provenance of a granitic rock can be defined at the scale of the intrusion. In addition, stones coming from two different intrusions from the same batholith can be distinguished. We conclude that the provenance of any granitic building stone is identifiable, especially if the intrinsic variability of a population of samples representative of that stone has been previously circumscribed. This study underlines that the compilation of databases for building stone identity cards is an essential first step toward the creation of official labels guaranteeing stone provenances.

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