Native copper formation associated with serpentinization in the Cheshmeh-Bid ophiolite massif (Southern Iran)

We would like to thank the two anonymous reviewers, and the editor Marco Scambelluri for their constructive and valuable comments and suggestions on our manuscript. Valentina Batanova and Valerie Magnin (ISTerre) are thanked for their help during the electron microprobe measurements. We would like to express our sincere gratitude to local people in Khajeh-Jamali village and workers from the Fars Chromite Company. The work of L. E. Aradi and Cs. Szabo was supported by the ELTE Institutional Excellence Program (TKP2020-IKA-05) managed by the Hungarian Ministry of Human Capacities. The work of G. Grieco was supported by the Italian Ministry of Education (MIUR) through the projects "PRIN2017 -Mineral reactivity, a key to understand large-scale processes" (2017L83S77) and " Dipartimenti di Eccellenza 2018-2022". C.M.s research has been funded by project PID2019-111715GB-I00/AEI/10.13039/501100011033.In the Cheshmeh-Bid district of the Khajeh-Jamali ophiolitic massifs (Southern Iran), mantle peridotites are intruded by abundant pyroxenite dykes. A few of these dykes are remarkable for the occurrence of native copper associated with the development of a metasomatic reaction zone. The dykes are progressively reacted, from their margins towards the center, with an amphibole + antigorite selvage, followed by a centimeter-thick clinopyroxene + antigorite assemblage and, finally, by the native copper-bearing zone consisting of clinopyroxene + chlorite + antigorite. Native Cu occurs along cleavages and partially healed fractures in clinopyroxene, and as massive grains intergrown with antigorite. Copper isotope signatures and thermodynamic calculations show that the main driver for reaction zone formation is Ca-metasomatism. Native copper forms at the expense of chalcocite in the reaction zone. Such a reaction can only occur in reducing conditions, in agreement with the analysis of fluid inclusions composition displaying H-2 and CH4. Such fluids presumably originated from the hydration of mantle rocks. The observed reaction zone and native copper mineralization are thus interpreted as the result of Ca-metasomatism during hydrothermal alteration of the oceanic lithosphere. This is consistent with U/Pb dating of titanite, suggesting formation during the Albian when the dykes were exposed on the seafloor in a supra-subduction setting. The source for copper mineralization, as revealed by Cu isotopes, is probably mantle-like.ELTE Institutional Excellence Program TKP2020-IKA-05Ministry of Education, Universities and Research (MIUR) 2017L83S77Ministry of Education, Universities and Research (MIUR) PID2019-111715GB-I00/AEI/10.13039/50110001103

Petrology and geochemistry of mafic and ultramafic cumulate rocks from the eastern part of the Sabzevar ophiolite (NE Iran): Implications for their petrogenesis and tectonic setting

The Late Cretaceous Sabzevar ophiolite represents one of the largest and most complete fragments of Tethyan oceanic lithosphere in the NE Iran. It is mainly composed of serpentinized mantle peridotites slices; nonetheless, minor tectonic slices of all crustal sequence constituents are observed in this ophiolite. The crustal sequence contains a well-developed ultramafic and mafic cumulates section, comprising plagioclase-bearing wehrlite, olivine clinopyroxenite, olivine gabbronorite, gabbronorite, amphibole gabbronorite and quartz gabbronorite with adcumulate, mesocumulate, heteradcumulate and orthocumulate textures. The crystallization order for these rocks is olivine chromian spinel → clinopyroxene → plagioclase → orthopyroxene → amphibole. The presence of primary magmatic amphiboles in the cumulate rocks shows that the parent magma evolved under hydrous conditions. Geochemically, the studied rock units are characterized by low TiO2 (0.18–0.57 wt.%), P2O5 (<0.05 wt.%), K2O (0.01–0.51 wt.%) and total alkali contents (0.12–3.04 wt.%). They indicate fractionated trends in the chondrite-normalized rare earth element (REE) plots and multi-element diagrams (spider diagrams). The general trend of the spider diagrams exhibit slight enrichment in large ion lithophile elements (LILEs) relative to high field strength elements (HFSEs) and positive anomalies in Sr, Pb and Eu and negative anomalies in Zr and Nb relative to the adjacent elements. The REE plots of these rocks display increasing trend from La to Sm, positive Eu anomaly (Eu/Eu* ¼ 1.06–1.54) and an almost flat pattern from medium REE (MREE) to heavy REE (HREE) region [(Gd/ Yb)N ¼ 1–1.17]. Moreover, clinopyroxenes from the cumulate rocks have low REE contents and show marked depletion in light REE (LREE) compared to MREE and HREE [(La/Sm)N ¼ 0.10–0.27 and (La/Yb)N ¼ 0.08–0.22]. The composition of calculated melts in equilibrium with the clinopyroxenes from less evolved cumulate samples are closely similar to island arc tholeiitic (IAT) magmas. Modal mineralogy, geochemical features and REE modeling indicate that Sabzevar cumulate rocks were formed by crystal accumulation from a hydrous depleted basaltic melt with IAT affinity. This melt has been produced by moderate to high degree (~15%) of partial melting a depleted mantle source, which partially underwent metasomatic enrichment from subducted slab components in an intra-oceanic arc setting

PETROLOGICAL CONSTRAINTS ON THE ORIGIN OF PYROXENITE DYKES IN THE LITHOSPHERIC MANTLE OF THE CHESHMEH-BID OPHIOLITIC MASSIF, SOUTHERN IRAN

The Cheshmeh-Bid ophiolitic massif in the Khajeh-Jamali district (Southern Iran) is dominated by harzburgite-dunite tectonites locally intruded by orthopy-roxenite dikes. These latter are composed of dominant coarse orthopyroxene with minor olivine, Cr-spinel, clinopyroxene and amphibole. Estimated equilibrium temperatures for Mg-hornblende and edenitic amphibole reveal a late stage magmatic origin.The Cheshmeh-Bid orthopyroxenites are characterized by very low Al2O3, CaO, Na2O and TiO2 abundances coupled to relatively high MgO and SiO2contents. They display U-shaped REE patterns, selective LILE enrichment and positive Pb and Sr anomalies. The host harzburgites are highly refractory mantle residues resulting from fluid-assisted melting. Field observations and mineral assemblages suggest that the pyroxenites formed by melt injection along fractures within rather cold ambient harzburgites and chromitites at moderate pressure (P > 1 GPa). Based on bulk-rock compositions and mineral chemistry, we infer that the Cheshmeh-Bid orthopyroxenites originated from the intrusion and crystallization of hydrous Si-rich, low-Ca melts with a boninite signature in a supra-subduction environment. Fine-grained neoblastic domains developed in the pyroxenites in response to subsolidus ductile deformation and recrystallization, which were most likely related to the exhumation of the Cheshmeh-Bid ophiolite massif

Petrology and geochemistry of mafic and ultramafic cumulate rocks from the eastern part of the Sabzevar ophiolite (NE Iran): Implications for their petrogenesis and tectonic setting

The Late Cretaceous Sabzevar ophiolite represents one of the largest and most complete fragments of Tethyan oceanic lithosphere in the NE Iran. It is mainly composed of serpentinized mantle peridotites slices; nonetheless, minor tectonic slices of all crustal sequence constituents are observed in this ophiolite. The crustal sequence contains a well-developed ultramafic and mafic cumulates section, comprising plagioclase-bearing wehrlite, olivine clinopyroxenite, olivine gabbronorite, gabbronorite, amphibole gabbronorite and quartz gabbronorite with adcumulate, mesocumulate, heteradcumulate and orthocumulate textures. The crystallization order for these rocks is olivine ​± ​chromian spinel → clinopyroxene → plagioclase → orthopyroxene → amphibole. The presence of primary magmatic amphiboles in the cumulate rocks shows that the parent magma evolved under hydrous conditions. Geochemically, the studied rock units are characterized by low TiO (0.18–0.57 ​wt.%), PO (<0.05 ​wt.%), KO (0.01–0.51 ​wt.%) and total alkali contents (0.12–3.04 ​wt.%). They indicate fractionated trends in the chondrite-normalized rare earth element (REE) plots and multi-element diagrams (spider diagrams). The general trend of the spider diagrams exhibit slight enrichment in large ion lithophile elements (LILEs) relative to high field strength elements (HFSEs) and positive anomalies in Sr, Pb and Eu and negative anomalies in Zr and Nb relative to the adjacent elements. The REE plots of these rocks display increasing trend from La to Sm, positive Eu anomaly (Eu/Eu∗ ​= ​1.06–1.54) and an almost flat pattern from medium REE (MREE) to heavy REE (HREE) region [(Gd/Yb) ​= ​1–1.17]. Moreover, clinopyroxenes from the cumulate rocks have low REE contents and show marked depletion in light REE (LREE) compared to MREE and HREE [(La/Sm) ​= ​0.10–0.27 and (La/Yb) ​= ​0.08–0.22]. The composition of calculated melts in equilibrium with the clinopyroxenes from less evolved cumulate samples are closely similar to island arc tholeiitic (IAT) magmas. Modal mineralogy, geochemical features and REE modeling indicate that Sabzevar cumulate rocks were formed by crystal accumulation from a hydrous depleted basaltic melt with IAT affinity. This melt has been produced by moderate to high degree (~15%) of partial melting a depleted mantle source, which partially underwent metasomatic enrichment from subducted slab components in an intra-oceanic arc setting.The authors thank the University of Isfahan (Isfahan, Iran) and the Instituto Andaluz de Ciencias de la Tierra (IACT, Granada, Spain) for their support in field work and sample preparation and for providing geochemical analyses facilities. We are grateful to Prof. Kristoffer Szilas, Prof. Tomo Morishita and two anonymous reviewers for their useful and constructive comments that improved the manuscript

Mastering technologies in design-driven innovations: how two Italian furniture companies make design a central part of their innovation process

Design is more and more viewed as an important strategic resource. However, even though there is a lot of talk about design, there are only a handful of companies that have truly mastered the design-driven approach to innovation. There is even less research that has tried to understand how these companies are able to successfully manage this approach. This paper aims to understand what it means to make design a central part of the business process, something able to add value to products and create new markets. More specifically, it focuses on the interplay between functional and semantic dimensions of a product. In-depth case studies about two leading Italian companies that operate in the furniture industry (Kartell and Luceplan) underline different interpretations of the role of technologies in radical innovations in product meanings. The empirical results highlight two main interpretations of the role of technologies in radical design-driven innovations: technologies as enablers of new product meanings, the importance of a supply network that allows to rapidly change product technologies and supports the experimentation of new ones

Metallogenic fingerprint of a metasomatized lithospheric mantle feeding gold endowment in the western Mediterranean basin

We thank the Associate Editor W.U. Reimold, and the referees T. Jalowitzki and M.L. Fioren-tini for their constructive reviews of the submitted version of the manuscript. This research was sup-ported by the BES-2017-079949 Ph.D. fellowship to ES. The Spanish projects PID2019-111715GB-I00/AEI/10.13039/501100011033 and RTI2018-099157-A-I00 provided funding for field emission gun-environmental scanning electron microscopy (FEG-ESEM) and electron microprobe microanaly-ses (EMPA) /laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of sulfides, respectively, while the Junta de Andalucia project FUMESA B-RNM-189-UGR18 financed LA-ICP-MS analyses of silicates. Research grants, infrastructures, and human resources leading to this research have benefited from funding by the European Social Fund and the European Regional Development Fund. We thank Jesus Montes Rueda (Universidad de Granada) , Isabel Sanchez Almazo (Centro de Instru-mentacion Cientifica [CIC] , Universidad de Granada) , Xavier Llovet (Centres Cientifics i Tecnolgics, Uni-versitat de Barcelona) , Miguel Angel Hidalgo La-guna (CIC, Universidad de Granada) , and Manuel Jesus Roman Alpiste (Instituto Andaluz de Ciencias de la Tierra, Consejo Superior de Investigaciones Cientificas-Universidad de Granada) for their careful technical assistance during sample preparation, FEG-ESEM, electron microprobe analyzes, and LA-ICP-MS analyses, respectively.Spinel peridotite xenoliths (one plagioclase- bearing) hosted in alkaline basalts from Tallante (southeast Spain) record the mineralogical and geochemical fingerprint of the subcontinental lithospheric mantle (SCLM) evolution beneath the southern Iberian margin. Mantle metasomatism in fertile lherzolites caused the crystallization of clinopyroxene + orthopyroxene + spinel clusters through the percolation of Miocene subalkaline melts during the westward migration of the subduction front in the western Mediterranean. In the Pliocene, heat and volatiles provided by alkaline host-magmas triggered very low melting degrees of metasomatic pyroxene-spinel assemblages, producing melt quenched to silicate glass and reactive spongy coronae around clinopyroxene and spinel. Refertilization of the Tallante peridotites induced the precipitation of base-metal sulfides (BMS) included in metasomatic clino- and orthopyroxene. These sulfides consist of pentlandite ± chalcopyrite ± bornite aggregates with homogeneous composition in terms of major elements (Ni, Fe, Cu) and semi-metals (Se, As, Te, Sb, Bi), but with wide variability of platinum-group elements (PGE) fractionation (0.14 < PdN/IrN < 30.74). Heterogeneous PGE signatures, as well as the presence of euhedral Pt-Pd-Sn-rich platinum-group minerals (PGM) and/or Auparticles within BMS, cannot be explained by conventional models of chalcophile partitioning from sulfide melt. Alternatively, we suggest that they reflect the incorporation of distinct populations of BMS, PGM, and metal nanoparticles (especially of Pt, Pd, and Au) during mantle melting and/or melt percolation. Therefore, we conclude that Miocene subalkaline melts released by asthenosphere upwelling upon slab tearing of the Iberian continental margin effectively stored metals in metasomatized domains of this sector of the SCLM. Remarkably high Au concentrations in Tallante BMS (median 1.78 ppm) support that these metasomatized domains provided a fertile source of metals, especially gold, for the ore-productive Miocene magmatism of the westernmost Mediterranean.Junta de Andalucia B-RNM-189-UGR18European Social Fund (ESF)European Commission BES-2017-079949 PID2019-111715GB-I00/AEI/10.13039/501100011033 RTI2018-099157-A-I0

On the properties of X-ray corona in Seyfert 1 galaxies

We carried out a uniform and systematic analysis of a sample of 112 nearby bright Seyfert 1 type AGN, the observations of which were carried out by the {\it Nuclear Spectroscopic Telescope Array (NuSTAR)} between August 2013 and May 2022. The main goal of this analysis is to investigate the nature of the X-ray corona in Seyfert 1 galaxies. From the physical model that fits the {\it NuSTAR} spectra, we could constrain the high energy cut-off ($\rm{E_{cut}}$) for 73 sources in our sample. For those 73 sources, we fitted the Comptonization model to estimate the temperature ($\rm{kT_{e}}$) of their corona. $\rm{kT_{e}}$ could be constrained in 42 sources. We investigated for possible correlations between various properties of the corona obtained from physical model fits to the observed spectra and between various coronal parameters and physical properties of the sources such as Eddington ratio and black hole mass. We found (a) a strong correlation between $\rm{E_{cut}}$ and the photon index and (b) a significant negative correlation between $\rm{kT_{e}}$ and the optical depth.Comment: 33 pages, 14 figures, Submitted to ApJ, comments are welcom

Mantle-to-crust metal transfer by nanomelts

The transfer of chalcophile metals across the continental lithosphere has been traditionally modeled based on their chemical equilibrium partitioning in sulfide liquids and silicate magmas. Here, we report a suite of Ni-Fe-Cu sulfide droplets across a trans-lithospheric magmatic network linking the subcontinental lithospheric mantle to the overlying continental crust. Petrographic characteristics and numerical calculations both support that the sulfide droplets were mechanically scavenged from the mantle source during partial melting and transported upwards by alkalinemagmas rising through the continental lithosphere. Nanoscale investigation by high-resolution transmission electron microscopy (HR-TEM) documents the presence of galena (PbS) nanoinclusions within the sulfide droplets that are involved in the mantle-to-crust magma route. The galena nanoinclusions show a range of microstructural features that are inconsistent with a derivation of PbS by exsolution from the solid products of the Ni-Fe-Cu sulfide liquid. It is argued that galena nanoinclusions crystallized from a precursor Pb(-Cu)-rich nanomelt, which was originally immiscible within the sulfide liquid even at Pb concentrations largely below those required for attaining galena saturation. We suggest that evidence of immiscibility between metal-rich nanomelts and sulfide liquids during magma transport would disrupt the classical way by which metal flux and ore genesis are interpreted, hinting for mechanical transfer of nanophases as a key mechanism for sourcing the amounts of mantlederived metals that can be concentrated in the crust.BES-2017-079949The Spanish projects PID2019-111715GB-I00/AEI/10.13039/501100011033NANOMET PID2022- 138768OB-I00MECOBE ProyExcel_00705(FEG-ESEM), focused-ion beam (FIB)High-resolution transmission electron microscopy (HR-TEM)Australian Research Council through ARC Linkage Project LP190100785European Social FundEuropean Regional Development Fun

Chromium Isotope Behavior During Serpentinite Dehydration in Oceanic Subduction Zones

Fluids released through the dehydration of serpentinite can be rich in Cl −, which enables the significant mobility of Cr in subduction zones. However, the Cr isotope behavior accompanying the mobility of Cr during serpentinite dehydration is still poorly constrained. Here, we report high-precision Cr isotope data for a unique suite of serpentinites that represent metamorphic products at different depths in oceanic subduction zones. Low-grade serpentinites affected by significant Cr loss during serpentinization exhibit remarkably higher δ 53Cr, while samples with Cr contents >∼1,800 ppm typically preserve mantle-like δ 53Cr. Antigorite serpentinites have an average δ 53Cr value of −0.17‰ ± 0.19‰ (n = 12, 2SD), which is statistically lower than those of low-grade serpentinite (−0.05‰ ± 0.30‰, n = 80, 2SD) and higher-grade chlorite harzburgite (−0.10‰ ± 0.27‰, n = 22, 2SD). This suggests that resolvable Cr isotope fractionation occurs during serpentinite dehydration, which is explained by the variability of Cr isotope behavior in the presence of Cl-bearing fluids at different dehydration stages. No obvious Cr isotope fractionation was found during chlorite harzburgite dehydration, probably related to the limited Cr mobility in a Cl-poor fluid. Other processes, such as melt extraction, external fluid influx and retrograde metamorphism, have negligible effects on the Cr isotope systematics of meta-serpentinites. Fluids released by serpentinite dehydration may have a great effect on the Cr isotope heterogeneity of mantle wedge peridotites and arc magmas.National Key Ramp;D Program of ChinaStrategic Priority Research Program (B) of CAS 2018YFA0702600National Natural Science Foundation of China (NSFC) XDB41000000Fundamental Research Funds for the Central Universities 42073029 41973004CNSAMICIN/AEI D020204FEDER program "Una manera de hacer Europa" PID2022-136471N-B-C21 C22 PID2019-111715GB-I00AEIFSE program "FSE invierte en tu futuro" RYC2018-024363-IJunta de AndaluciaEuropean Union (EU) Postdoc_21_00791European Social Fund (ESF)Junta de Andalucia RNM-131 RNM-37