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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.

The Scottish Alliance of Geoscience, Environment and Society (SAGES) was launched in May 2007 and thrives to this day (). It is a major research partnership between ten institutions in Scotland squarely focused on the prime problem of our time, namely understanding how the natural world works and how it interacts with human society. The inspiration driving SAGES is that we can all contribute more if we collaborate. Paul Bishop was a staunch believer in collaboration and played a pivotal role in the building of SAGES. The early history of SAGES and Paul's contribution is little known and it seems fitting to address this in a special issue in his name. [ABSTRACT FROM AUTHOR]

Iron oxide -Cu ± Au ± U ± Co (IOCG) mineralization is associated with numerous Proterozoic breccia bodies, collectively known as Wernecke Breccia, in Yukon Territory, Canada. Multiphase breccia zones occur in areas underlain by Paleoproterozoic Wernecke Supergroup metasedimentary rocks and are associated with widespread sodic, potassic, and carbonate alteration assemblages. Fluid inclusion data indicate syn-breccia fluids were hot (185-350°C) saline (24-12 wt.% NaCl equivalent) NaCl-Ca[Cl.sub.2]-[H.sub.2]O brines. Estimates of fluid pressure vary from 0.4 to 2.4 kbar (1 kbar = 100 MPa). Carbon and oxygen isotopic compositions of breccia-related carbonates range from ~-11 ‰ to +1.5 ‰ (Pee Dee belemnite (PDB)) and -2 ‰ to 20 ‰ (Vienna standard mean ocean water (V-SMOW); [δ.sup.18] [O.sub.water] ~-8 ‰ to +15 ‰), respectively. δ[sup.13]C and δ[sup.18]O values for host Wernecke Supergroup limestone/dolostone vary from ~-2 ‰ to 1.6 ‰ and 12 ‰ to 25 ‰, respectively. Sulfur isotopic compositions of hydrothermal sulfides and sulfate vary from ~-12 ‰ to +13 ‰ and +8 ‰ to +17 ‰ (Canon Diablo Troilite (CDT)), respectively. Syn-breccia biotite, muscovite, and actinolite have δD and δ[sup.18]O values of ~-141 ‰ to -18 ‰ and +7 ‰ to +12 ‰ (V-SMOW; [δ.sup.18][O.sub.water] ~7 ‰ to 11 ‰), respectively. The Wernecke Breccias and the associated IOCG mineralization appear to have formed from largely nonmagmatic fluids--based on isotopic, fluid inclusion, and geological data. The emerging hypothesis is that periodic overpressuring of dominantly formational/metamorphic water led to repeated brecciation and mineral precipitation. The weight of overlying sedimentary rocks led to elevated fluid temperatures and pressures; fluid flow may have been driven by tectonics and (or) gravity with metals scavenged from host strata. Une mineralisation d'oxyde de fer--Cu ± Au ± U ± Co (IOCG) est associee a de nombreux amas de breches datant du Proterozoique, connus ensemble sous le nom de breches de Wernecke, dans le Territoire du Yukon, Canada. Des zones de breches a plusieurs phases se retrouvent dans les secteurs reposant sur des roches metasedimentaires du supergroupe de Wernecke (Paleoproterozoique) et ces zones sont associees a des assemblages etendus d'alteration sodique, potassique et de carbonate. Des donnees sur des inclusions de fluides indiquent que les fluides contemporains des breches etaient des saumures NaCl-Ca[Cl.sub.2]-[H.sub.2]O chaudes (185-350°C) et salines (24-42 % poids equivalent NaCl). Des estimations de la pression des fluides varient de 0,4 a 2,4 kbar (1 kbar = 100 MPa). Les compositions isotopiques en carbone et en oxygene des carbonates relies aux breches varient respectivement de ~-11 ‰ a +1,5 ‰ (Pee Dee belemnite (PDB)) et -2 ‰ a 20 ‰ (Vienna standard mean ocean water (V-SMOW); δ[sup.18]O eau ~-8 ‰ a +15 ‰). Les valeurs δ[sup.13]C et δ[sup.18]O pour les dolomies/calcaires encaissants du supergroupe de Wernecke varient respectivement de ~-2 ‰ a 1,6 ‰ et de 12 ‰ a 25 ‰. Les compositions isotopiques du soufre des sulfures et sulfates hydrothermaux varient respectivement de ~-12 ‰ a +13 ‰ et de +8 ‰ a +17 ‰ (Canon Diablo Troilite (CDT)). La biotite, la muscovite et l' actinote contemporaines de la breche ont respectivement des valeurs δD et δ[sup.18]O de ~-141 ‰ a -18 ‰ et de +7 ‰ a +12 ‰ (V-SMOW; δ[sup.18]O eau :7 ‰ a 11 ‰). En se basant sur des donnees d'isotopes, d'inclusion de fluides et geologiques, il semblerait que les breches de Wernecke et la mineralisation IOCG associee aient ete formees a partir de fluides en grande partie non magmatiques. L'hypothese resultante est que la surpression periodique de l'eau, surtout de formation/metamorphique, a conduit a beaucoup de brechification et de precipitation de mineraux. Le poids des roches sedimentaires sus-jacentes a mene a des temperatures et a des pressions elevees dans les fluides; les fluides peuvent avoir ete pousses a couler par tectonisme et (ou) par gravite et contenir des metaux recuperes des strates hotes. [Traduit par la Redaction], Introduction Numerous Proterozoic breccia bodies, collectively known as Wernecke Breccia, occur over large areas in the north-central Yukon Territory, Canada (Fig. 1; e.g., Bell and Delaney 1977; Archer et al. [...]