Lead-isotope evidence for a Hercynian origin of the Salsigne gold deposit (Southern Massif Central, France)

✍ Scribed by M. Guen; J. L. Lescuyer; E. Marcoux

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 803 KB
• Volume: 27
• Category: Article
• ISSN: 0026-4598
• DOI: 10.1007/bf00197097

✦ Synopsis

The Salsigne gold deposit contains a complex association of sulphide layers, gold-rich disseminations, quartz-bearing veins and flat reefs, which are hosted by folded and slightly metamorphosed Paleozoic sediments on both sides of a major thrust zone. It is demonstrated that these various Au-As ore types have similar lead-isotope compositions (206pb/2O4pb = 18.22-18.56), which are characteristic of Hercynian ore deposits in the southern Massif Central. The Lower Cambrian to Devonian host rocks and associated Pb-Zn-Ba occurrences display distinctly less radiogenic corrected isotopic signatures (2~176 = 17.83-17.98), which are characteristic of Cambrian lead in the Montagne-Noire. Concerning the controversial origin of the Salsigne gold mineralization, these results disagree with the former syngenetic hypothesis and support a new model of Hercynian syntectonic gold concentration.