In the northern Tyrrhenian Sea, late Miocene \ud intrusions (Monte Capanne pluton and\ud Porto Azzurro pluton) were emplaced at\ud upper crustal levels (<0.2 GPa) in the thrust\ud systems of Elba Island. The emplacement\ud of intrusive rocks is currently explained\ud in the context of late Miocene extensional\ud tec tonics. New detailed structural data\ud collected along a continuous natural cross\ud section through the contact aureole of the\ud Porto Azzurro pluton (eastern Elba) where\ud strain localization has occurred within two\ud west-dipping decameter-scale carbonate\ud shear zones, namely the Calanchiole and\ud Felciaio shear zones, are reported here.\ud These shear zones, characterized by a lithological\ud difference with calcite and dolomite\ud marbles dominant in the Calanchiole and\ud Felciaio shear zones, respectively, exhibit\ud a similar rheological behavior . They represent\ud two weakened layers in which westdipping\ud mylonitic foliation, sheath folds,\ud boudinage structures, and upright folds\ud developed within the contact aureole .\ud Moreover, in correspondence with the\ud Felciaio shear zone, the inversion of metamorphic\ud facies occurs. Meso- and microstructural\ud data give evidence that most of\ud the deformation and displacement in the\ud shear zones was coeval with contact metamorphism\ud and developed under metamorphic\ud conditions retrograde from pyroxene\ud hornfels to hornblende-hornfels facies.\ud Geometric and kinematic features indicate\ud that both shear zones correspond to ductile\ud thrusts, which led to internal stacking of the\ud contact aureole . Therefore, at Elba Island,\ud emplacement of intrusive rocks coeval with\ud late Miocene crustal shortening gives a new\ud perspective on relations between tectonics\ud and magmatism in the northern Apennines

The Monte Corchia cave system, one of the most famous and popular caves in Italy, has in recent times been the subject of investigation on its speleothems as paleoclimate archives. This paper describes the geology, geomorphology and water chemistry of the cave system with the aim to elucidate the processes that have generated these speleothems and the properties they contain that are so useful for paleoclimatology. Some general conclusions can be drawn: i) the Corchia system is a cave developed over different altitudes during progressive uplift of the mountain chain in which it is located, probably under drainage conditions very different to those of the present. This has allowed the development of a large (ca. 60 km) and deep (-1187 m) karst system; ii) the dewatering phases have left the deepest chambers far away from clastic input and with long drip pathways; iii) the peculiar geological context has permitted the water to intercept and dissolve a significant source of U (still unknown) that facilitates radiometric dating; iv) in the last 1 Ma at least, no significant changes have occurred in the relief and in the epikarst, in the sense that speleothems have grown under very similar conditions. In addition the extremely low Ca concentration of drip waters have permitted low speleothem growth rates and, at least for the "Galleria delle Stalattiti", the zone under paleoclimate studies, a stable plumbing system (i.e. chemistry and stable isotopes of drip waters) has produced calcite close to isotopic equilibrium.

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