caa a22 4500 445390166 CHVBK 20180317143044.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s00710-010-0138-2 doi (NATIONALLICENCE)springer-10.1007/s00710-010-0138-2 Pyrite tracks assimilation of crustal sulfur in Pyrenean peridotites [Elektronische Daten] [Jean-Pierre Lorand, Olivier Alard] Cobalt-bearing pyrite (0.5-2.0wt.% Co) is abnormally abundant (up to 35vol.% of the total volume of the sulfide phase) in some eastern Pyrenean peridotite massifs, compared to pieces of subcontinental mantle studied so far for sulfides. Pyrite occurs as vermicular intergrowths inside pentlandite and/or chalcopyrite or as coarser, blocky grains in the intergranular pores of host peridotites. Those different pyrites are characterized by different platinum-group element systematics (measured by laser ablation microprobe and ICP-MS). Vermicular pyrite intergrown with pentlandite displays Os-, Ir-, Ru- and Rh-enriched chondrite normalized PGE patterns of Monosulfide solid solution (Mss). In contrast, coarse-grained intergranular ("blocky”) pyrites, are PGE-poor. Chalcophile trace elements (i.e. Zn, Pb, Ag, Au) that are not usually concentrated in mantle-derived sulfides were commonly detected. By contrast, selenium contents are generally low, yielding thus pyrite with high S/Se ratio (>105), consistent with a sedimentary sulfur source. Pyrite microtextures and chalcophile trace element contents support a process of assimilation of crustal sulfur from the metamorphosed sedimentary country rocks. These latter generated highly reactive CO2-S fluids, which were injected into structural discontinuities of the lherzolitic bodies. Sulfur has reacted at T = 300-550°C with pre-existing, mantle-derived, metal-rich sulfide assemblages (pentlandite-chalcopyrite). Addition of crustal sulfur did produce Mss which, on cooling, exsolved the Os-rich pyrite in addition to pentlandite. The coarse-grained pyrite types have crystallized directly from S-rich fluids. Springer-Verlag, 2010 Lorand Jean-Pierre Laboratoire de Minéralogie et Cosmochimie (CNRS UMR 7202), Muséum National d'Histoire Naturelle, CP 52, 61 Rue Buffon, 75005, Paris, France aut Alard Olivier Géosciences Montpellier, CNRS UMR 5243, Université de Montpellier II, Cc 60, Place Eugène Bataillon, 34095, Montpelier Cédex, France aut Mineralogy and Petrology Springer Vienna 101/1-2(2011-01-01), 115-128 0930-0708 101:1-2<115 2011 101 710 https://doi.org/10.1007/s00710-010-0138-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00710-010-0138-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lorand Jean-Pierre Laboratoire de Minéralogie et Cosmochimie (CNRS UMR 7202), Muséum National d'Histoire Naturelle, CP 52, 61 Rue Buffon, 75005, Paris, France aut NATIONALLICENCE 700 1- Alard Olivier Géosciences Montpellier, CNRS UMR 5243, Université de Montpellier II, Cc 60, Place Eugène Bataillon, 34095, Montpelier Cédex, France aut NATIONALLICENCE 773 0- Mineralogy and Petrology Springer Vienna 101/1-2(2011-01-01), 115-128 0930-0708 101:1-2<115 2011 101 710 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer