C. Caron et al., A MIXED CRUSTAL SOURCE MODEL FOR THE IGLE SIENTE PB-ZN ORE-DEPOSITS (SW SADINIA) - LEAD-ISOTOPE EVIDENCE, Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre, 317(8), 1993, pp. 1073-1080
Lead isotope analyses applied to the major stratabound Pb-Zn ore depos
its hosted in Lower Cambrian carbonates of SW Sardinia reveal, despite
the apparent homogeneity of the data, the existence of significant va
riations between the Cambrian host rocks and the associated sulfides.
These results are interpreted by a mixed crustal source model involvin
g the Paleozoic sedimentary pile of SW Sardinia and an old crustal com
ponent, similar to the pre-Variscan basement of the Eastern Pyrenees.
Furthermore, preliminary data would support the long-held assumption o
f a Mississippi-Valley-type origin for these deposits, but involving a
major remobilization of disseminated Cambrian metals during the Early
Ordovician ''Sardic tectonic phase''.