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A revaluation of the Co/Ni ratio in pyrite as geochemical tool in ore genesis problems 总被引:9,自引:0,他引:9
On the basis of a sound evaluation of literature's data, the Co/Ni ratio in pyrite proves a more reliable indicator in ore genesis than previously retained. This is particularly true for volcanogenic pyritic ores which are constantly characterized by Co/Ni values (>5 but more often >10) definitely higher than those attained by sedimentary or hydrothermal pyrites. Moreover, once stated that an appropriate sampling has been performed, such geochemical studies, extended to as many deposits as possible from a same area, may provide relevant insights into the metallogenic history of the given area. On the basis of their Co/Ni ratios the Southern Tuscany ores fit in a two-stage metallogenic model: a primary (Paleozoic) emplacement of volcanogenic massive-sulfide deposits, in a sub-marine volcanic-exhalative environment, followed by later (Mio-Pliocenic) deposition of smaller, prevalently replacement deposits through hydrothermal partial mobilization of the older ones. The research of new ores may benefit from these geochemical studies too. 相似文献
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Zamponi Joaquin Giannetti Andrea Bovino Stefano Sabatini Giovanni Schleicher Dominik R. G. Krtgen Bastian Reissl Stefan Wolf Sebastian 《Astrophysics and Space Science》2022,367(6):1-9
Astrophysics and Space Science - Dynamical evolution of galaxies is a complex process, especially the centers. Gravitationally coupled gas and stellar discs have been observed to coexist in the... 相似文献