The Apuane Alps core complex underwent polyphasic deformation and greenschist facies metamorphism during the Apenninic orogeny. Several types of ore deposits occur within its Palaeozoic basement. At Pollone, barite-pyrite-polymetallic stratiform (syngenetic) bodies and metamorphogenic veins are spatially associated. 87Sr/86Sr ratios appear to be systematically higher in vein barites than in stratifonn bodies. Wall rocks appear to be isotopically unaffected by mineralising fluid circulation since very short distances from orebodies. These features suggest a scarce remobilization of stratiform barite and a channelled, rather than pervasive, style of circulation of mineralising fluids. The relatively high 87Sr/86Sr ratio in vein barites points toward a radiogenic source for Sr. In agreement with a previous study of host rock Rb geochemistry, radiogenic Sr may have been released by the breakdown of Rb-bearing silicates in basement rocks.
Sr-isotope composition of barite veins from the Pollone deposit (Apuane Alps, Tuscany, Italy) / Costagliola P.; Barbieri M.; Benvenuti M.; Lattanzi P.; Castorina F.. - STAMPA. - (1995), pp. 341-344. (Intervento presentato al convegno 3rd biennial SGA Meeting tenutosi a Prague nel 28-31 August 1995).
Sr-isotope composition of barite veins from the Pollone deposit (Apuane Alps, Tuscany, Italy)
COSTAGLIOLA, PILARIO;BENVENUTI, MARCO;LATTANZI, PIERFRANCO;
1995
Abstract
The Apuane Alps core complex underwent polyphasic deformation and greenschist facies metamorphism during the Apenninic orogeny. Several types of ore deposits occur within its Palaeozoic basement. At Pollone, barite-pyrite-polymetallic stratiform (syngenetic) bodies and metamorphogenic veins are spatially associated. 87Sr/86Sr ratios appear to be systematically higher in vein barites than in stratifonn bodies. Wall rocks appear to be isotopically unaffected by mineralising fluid circulation since very short distances from orebodies. These features suggest a scarce remobilization of stratiform barite and a channelled, rather than pervasive, style of circulation of mineralising fluids. The relatively high 87Sr/86Sr ratio in vein barites points toward a radiogenic source for Sr. In agreement with a previous study of host rock Rb geochemistry, radiogenic Sr may have been released by the breakdown of Rb-bearing silicates in basement rocks.
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