In eastern Elba Island (Tuscany, Italy), a shallow crustal level felsic, tourmaline-bearing, dyke-sill swarm of Late Miocene age is associated with abundant tourmaline-quartz hydrothermal veins and metasomatic masses. Development of these veins and masses in the host rocks demonstrates multiple hydro-fracturing by magmatic, boron-rich saline fluid. Tourmalines in felsic dykes are schorl, whereas in veins and metasomatic masses, tourmaline composition ranges from schorl-dravite through dravite to uvite. This compositional shift is evidence for an increasing contribution to the magmatic boron-rich fluids by a Mg-Ca-Ti-rich external component represented by biotite-rich and amphibolite host rocks. This system can be envisaged as an exposed proxy of the high temperature hydrothermal system presently active in the deepest part of the Larderello-Travale geothermal field (Tuscany).
|Autori:||DINI A.; MAZZARINI F.; MUSUMECI G.; ROCCHI S.|
|Titolo:||Multiple hydro-fracturing by boron-rich fluids in the late Miocene contact aureole of eastern Elba island (Tuscany, Italy)|
|Anno del prodotto:||2008|
|Digital Object Identifier (DOI):||10.1111/j.1365-3121.2008.00823.x|
|Appare nelle tipologie:||1.1 Articolo in rivista|