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Sm-Nd dating of fluorite from the worldclass Montroc fluorite deposit, southern Massif Central, France

M. Munoz·W. R. Premo·P. Courjault-Rade
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Abstract

A three-point Sm-Nd isotope isochron on fluorite from the very large Montroc fluorite vein deposit (southern Massif Central, France) defines an age of 111??13 Ma. Initial ??Nd of -8.6 and initial 87Sr/86Sr of ???0.71245 suggest an upper crustal source of the hydrothermal system, in agreement with earlier work on fluid inclusions which indicated a basinal brine origin. The mid-Cretaceous age of ???111 Ma suggests the Albian/Aptian transition as the most likely period for large-scale fluid circulation during a regional extensional tectonic event, related to the opening of the North Atlantic ocean. ?? Springer-Verlag 2004.

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M. Munoz, W. R. Premo, P. Courjault-Rade. 2004-12-14. Sm-Nd dating of fluorite from the worldclass Montroc fluorite deposit, southern Massif Central, France. https://doi.org/10.1007/s00126-004-0453-9

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