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International audience; Nearly 300 million t of phosphogypsum (PG) are produced every year as a byproduct from phosphate fertilizer production worldwide. Approximately 58% of the PG are stacked, 28% are discharged in coastal waters and only 14% are further processed. This critical review provides an overview of the physical-chemical properties of PG produced from sedimentary and magmatic phosphate ore worldwide using various analytical tools. Results from more than 25 years of work on PG at École des Mines de Saint-Étienne are presented and critically discussed. In total PG samples from 67 industrial storage sites around the world and PG samples synthesized under different conditions in the laboratory have been considered. The low radioactivity present in PG (particularly PG produced from sedimentary phosphate rock) was identified as the main challenge to using PG as a raw material in construction. Water-soluble and volatile chemical compounds were identified as the main challenge to environmentally sound PG management. Although PG does (in most cases) not pose an immediate threat to the environment the authors recommend processing all PG instead of storing or disposing it, to eliminate potential long-term risks and utilize a relevant secondary resource.

The first magmatic event that post-dates the Meso-Cretaceous orogeny in the Carpatho-Balkan area took place in the Upper Cretaceous at the same time and after the formation of Gosau-type molasses basins, the whole being controlled by an extensional tectonic transpressive-transtensive type (Schuller, 2004; Schuller et al., 2009; Drew, 2006; Georgiev et al., 2009). This tectonic regime controlled the spatial and temporal distribution of both magmatites and metallogenesis associated with the main feature discontinuity.This aspect is suggested by gravimetry and magnetism studies (Andrei et al., 1989), and also structural studies (Schuller et al., 2009; Drew, 2006; Georgiev et al., 2009).The age data attest to the temporal sequentially of Upper Cretaceous magmatism's evolution in the Carpathians and the Balkans. The most accurate age data (using geochronometers of zircon U-Pb and molybdenite Re-Os) suggest a very narrow evolutionary range (70.2-83.98 Ma, after Nicolescu et al., 1999; Galhofer, 2015 and 72.36-80.63 Ma, after Ciobanu et al., 2002; Zimmerman et al., 2008), which is characteristic to short-lived magmatism. In contrast, the same magmatism exists between 84-86 Ma in Serbia (Bor-Madjanpek district) and between 86-92 Ma and 67-70 Ma in Bulgaria (Srednogorie massif) in the Rhodope massif (von Quadt et al., 2007).The magma volumes have been significant several times, so much so that we have circumstances such as that in Vlǎdeasa (Apuseni Mts), and not only, in which sedimentary deposits of the Gosau type are "suspended" at high altitude, "behind" the granodiorite intrusions. According to Lin & Wang (2006), there are two approaches to explain this situation in the Carpathians during Upper Cretaceous: (1) mechanical convective ablation of the lithosphere, as suggested by Bird (1979) for North American mountain ranges, or (2) detachment of a large piece of the lithospheric mantle, as suggested by Houseman et al. (1981). The thin crust can be explained in an extensional context, regardless of the adopted model, which facilitates rapid ascents of magmas induced by adiabatic detente at the base of the lithosphere and/or in the asthenosphere.Irregular variations in LaN/YbN, Eu/Eu*, Ce/Ce*, and initial 87Sr/86Sr, and 143Nd/144Nd ratios that are in the range between 0.704957-0.706774 and 0.512456-0.512538 respectively, suggest that the banatites were generated by partial melting of the LCC, with the involvement of mantle-derived magmas.The metallogenesis associated with banatitic magmatism is characterized by a great typological variety of metalliferous accumulations forming mineral deposits with main commodities of Fe, Cu, Pb, Zn, ± Au, Ag, W, Mo, B, Mg, Te, Bi, Sb, spatially dominated by transpressive-transtensive tectonics. The most common forms of mineralization is skarn, porphyry copper, massive sulfide, and veins. These mineral deposits exibit complex paragenesis of more than 200 minerals, some of which were first described: ludwigite, szaibelyite, dognacskaite, rezbanyite, veszelyite and csiklovaite. The main mineral deposits associated with the Romanian banatites are Baita Bihor (Mo-Bi-W-Cu-U-Pb-Zn-B), Baisoara (Fe-Zn-Pb), Ocna de Fier-Dognecea (Fe-Cu-Pb-Zn-Bi), Moldova Noua (porphyry Cu±Au-Ag-Mo), Oravita-Ciclova (Cu-Mo-W-Bi) and Sasca (Cu-Mo). AcknowledgmentsThis work was supported by two PNCDI III grants of the Romanian Ministry of Research and Innovation, PN-III-P1-1.2-PCCDI-2017-0346/29 and PN-III-P4-ID-PCCF-2016-4-0014.

Voia deposit belongs to the Săcărâmb-Cetraș-Cordurea Miocene volcano-tectonic alignment of the South Apuseni Mountains, Romania. This large volcanic complex represents a Sarmatian-Pannonian magmatic-hydrothemal mega-system of around 5 km2 with an estimated 3–4 Ma time-space evolution, consisting of seven andesitic volcanic structures grouped in a circle, three subvolcanic andesite-quartz porphyry microdiorite and associated porphyry Cu-Au(Mo), pyrite Ca-Mg skarns and epithermal Au-Ag-Pb-Zn-Cu mineralizations.The mineral assemblages of alteration and mineralization processes belong to several mineralized zones on a vertical scale, according to sampling evidence and laboratory studies. HS products are found in the upper part of the structure (300-500 m), with dominant advanced and intermediate argillic alterations and sulfide-sulfate gold-poor veins (pyrite, marcasite, base metal sulfides, Fe-Ti oxides, vuggy quartz, alunite, gypsum, anhydrite). Within the 500-1200 m depth, the HS mineral assemblages gradually decrease in favor of IS and LS products. It is characterized by the coexistence of gold-rich LS assemblage (native gold, base metal sulfide, adularia, sericite-illite, chlorite, carbonates ± anhydrite veins), with the IS assemblage (iron oxides, chalcopyrite, pyrite, quartz, anhydrite). These assemblages overprint the HS mineral associations, resulting in a transition zone characterized by gold - pyrite - chalcopyrite - iron oxides - quartz - anhydrite mineral assemblage characteristic for HS and native gold - pyrite - base metal sulfides - carbonates - quartz mineral assemblage corresponding to IS+LS type.Gold is present in all of the identified mineralization forms: porphyry-epithermal Cu-Au, epi-mesothermal carbonate veins with gold - base metal sulfides, quartz veins with pyrite - chalcopyrite - magnetite ± hematite ± anhydrite, anhydrite veins with base metal sulfides and sulfosalts, anhydrite veins with pyrite - anhydrite ± quartz, vuggy quartz (silica residue) with gold-poor pyrite veins and impregnations in porphyry systems.Drilling core samples revealed that in Voia deposit, gold is concentrated in chalcopyrite (drills no. 7, 19, 37) along with pyrite - magnetite - hematite - quartz assemblage from the late potassic stage. The major amount of gold associated with chalcopyrite tends to be mainly submicroscopic. Pyrite from anhydrite veins of the early potassic stage ± phyllic alteration is relatively poor in gold (drills no. 1-6, 8-14). However, the highest gold contents are present in pentagonal dodecahedron pyrites (drills no. 33, 38, 39) of pyrite-chalcopyrite-magnetite ± hematite-quartz assemblage from late potassic stage ± phyllic alteration. Pyrite associated with magnetite from anhydrite veins tends to be poor in gold (drills no. 8, 11, 15, 28, 29). A carbonate vein containing gold-bearing base metal sulfides that was intercepted at 960,00-960,30m depth by drill no. 17 is one of the richest in gold.Native gold occurs as fine inclusions in ore minerals (5-20 μm). Large irregular grains of native gold (>50 μm) appear at mineral boundaries and along the fissures. The gold color is bright yellow and has a measured Au:Ag ratio of 5:1, suggesting that native gold has been formed at a relatively high temperature.Acknowledgments: This work was supported by two Romanian Ministry of Research and Innovation grants: PN-III-P4-ID-PCCF-2016-4-0014 and PN-III-P1-1.2-PCCDI-2017-0346/29.

The mining industry has been a significant part of the economy for many decades. Continuous pollution of the environment with heavy metals has been caused by mineral resources exploration and exploitation activities, as well as by processing of ores in factories. The use of vegetation for soil reclamation is called phytoremediation, and it is successfully utilized to extract heavy metals from soil and restore the soil to a healthy level. The gold mining industry is a continuous pollution trigger, representing the primary source of heavy metal contamination during the exploitation and for many decades after the mining activity is ceased if the mining area is not environmentally cleaned. Gold mine tailings contain high levels of toxic metals such as Cu, Pb, Zn, Cd, As, and Hg with a negative influence on the environment. Phytoremediation technology can represent a low-cost option for the remediation of industrially contaminated areas, especially for abandoned mines. Various associations and interactions between plants, their microbial rhizosphere flora, and pollutants make the phytoremediation mechanisms practical for a variety of organic and inorganic contaminants. Various phytoremediation methods can be widely used for the treatment of various solid, liquid, and gaseous substrates, in the decontamination of macronutrients (phosphate and nitrate), several elements (Pb, Cu, Zn, Cd, Fe, As, Mn, Ni, Mo, Cr, Co, F, Hg, Se, V, and W), radioactive isotopes (238U, 137Cs, and 90Sr), petroleum hydrocarbons, organic solvents, and herbicides.

During the Meso-Cretaceous compressive tectonic event (marked by the subduction of the East European Platform under Gondwana, and the initiation of the creation of accretionary prism in front of the orogen) the absence of related magmatism, and implicitly, the lack of an "arc" is similar to that of the Alps (McCarthy et al., 2018). Afterward, in the Upper Cretaceous, the Carpathian area has evolved in an extensional geodynamic context, specific to post-collisional periods, marked by the appearance of sedimentary basins with complex evolution and Gosau type molasses (Schuller, 2004; Schuller et al., 2009). In connection to the above, or not, it has evolved a complex magmatism, from a compositional point of view and as manifestation, largely calc-alkaline, known in the geological literature as banatitic (von Cotta, 1864). Banatitic magmatism is the first such manifestation in the Carpathians, post-subduction and post-collision and the most reliable age data (using U-Pb on zircon and Re-Os on molybdenite methods) suggest a very narrow range of evolution (70.2 - 83.98 Ma, Nicolescu et al., 1999; Galhofer, 2015; 72.36 - 80.63 Ma, Ciobanu et al., 2002; Zimmerman et al., 2008), that is characteristic to short-lived magmatism. Comparatively, in Serbia (Bor-Madjanpek district), the same magmatism occurs between 86-84 Ma, in Bulgaria in the Srednogorie massif between 92-86 Ma and Rhodope massif at 67-70 Ma (von Quadt et al., 2007). The geodynamic models discussed for this type of magmatism suggest, almost all without exception, the existence of subductions that would have extended as activity from the Middle Cretaceous to the Paleogene. Or, the realities of the terrain show that this magmatism seals the mesocretacic compressive structures (napes), as Nicolescu et al. (1999) exposed for the first time in Banat region. The situation is similar in the Apuseni Mountains. From the presumption of the generation of subductions for this magmatism, the idea of an "L" form magmatic belt ("arc"), from the Apuseni Mountains to Bulgaria, was forced. If we look closely at the spatial distribution of intrusive and effusive bodies, aspect also revealed by gravimetry studies (Andrei et al. 1989), we observe that they occupy areas with specific geometries, linked to or close to the Gosau-type basins, but strictly controlled by strike-slip fractures, similar to those that have controlled the appearance of Gosau basins (Drew, 2006). The metallogenesis associated with this magmatism is represented by metalliferous accumulations of Fe, Cu, Pb, Zn, with Au, Ag and W, Mo, B, Mg, Te, Bi, Sb, with a great typological variety, spatially controlled by the same type of fractures. It is evident that the transpressive-transtensive regime worked throughout the entire range of magmatic and metallogenetic activity, controlling it. In Banat region, as well as in the Apuseni Mountains, the end of the magmatic activity ceases with mineralizing and/or bearing mineralization lamprophyres. Being so, probably the lamprophyres attend or announce the metallogenetic event.AcknowledgmentsThis work was supported by two grants of the Romanian Ministry of Research and Innovation, project number PN-III-P4-ID-PCCF-2016-4-0014, and project number PN-III-P1-1.2-PCCDI-2017-0346/29, both within PNCDI III

The study has focused freshwater mussels to determine the risk of water pollution. We have shown that freshwater mussels are a good bioindicator for monitoring over time this type of water pollution due to their ability to filter water from the river. The entire food chain (freshwater mussels, mollusc, shrimp, fish, birds and humans) is affected by the pollution. The Saint Etienne (France) has a large industrial and mining history. The end of these activities has given way to industrial wasteland and mine dumps. Leaching by rain industrial and mining waste may generate a very large urban pollution. Rivers (Ondaine and Loire) and lakes (Saint–Victor–sur–Loire) downstream of this zone are highly polluted by heavy metals.

International audience; This paper presents the results of the new investigations by optical microscopy, scanning electron microscopy (SEM) and electron-probe micro-analysis (EPMA) performed on samples collected from Orlea adit from Roşia Montană Au-Ag deposit, Romania. Based on composition, three types of Au-Ag alloy were described. At Roşia Montană, galena, pyrite, chalcopyrite and sphalerite are intimately associated with gold, electrum and tellurium-bearing minerals. At Roşia Montană, the precipitation of Au-Ag alloy with variable composition can be assigned to compositional changes of the parent hydrothermal solutions during deposition due to boiling, fluid dilution and cooling.

International audience; This paper presents the geochemical data distribution of Cr, Cd, Cu, Co, Ni, Pb, Zn and Ba heavy metals in Vereda soils, located in the Rio Formoso basin, using a sampling network of vertical profiles, in order to assess the current condition of these environments. Considering that it comes to areas located near agroforestry activities, these elements were selected because they are present in pesticides and fertilizers and represents the major sources of contamination. The heavy metal content found in soils requires attention considering that many of them are beyond the limits of prevention set by CONAMA Resolution 420/2009. Geo-accumulation Index and Contamination Factor calculations revealed that these Veredas have high soil contamination by metals, particularly with Ni, Zn and Ba. Thus, the implementation mechanisms are necessary conducive to the protection of these environments as they are important to the region. It is suggested to create protected areas of sustainable use modality, specifically areas of ecological interest for the protection of Veredas, this being considered strategic to the conservation of soil and water.

International audience; Saint Etienne (France) has a large industrial and mining history. The end of these activities has given wayto industrial wasteland and mine dumps. Leaching caused by rain, industrial and mining waste may generate a verylarge urban pollution. Rivers (Ondaine and Loire) and lakes (Saint-Victor-sur-Loire) downstream of this zone arehighly polluted by heavy metals. The study has focused freshwater mussels to determine the risk of water pollution.We have shown that freshwater mussels are a good bioindicator for monitoring over time, this type of waterpollution due to their ability to filter water from the river. The entire food chain (freshwater mussels, mollusk,shrimp, fish, birds and humans) is affected by the pollution.

International audience; XRF methods were used to evaluate the impact of uranium mine dumps on the stream sediments from Crucea region (Romania). In order to estimate the natural and anthropogenic inputs of radioactive and heavy metals in the sediments, normalization to Al was applied. The pollution degree of the bottom sediments show that U, Th and Pb reach medium and punctual high values, while the rest of the elements appears in concentrations close to the background or lower. The measurements carried out in the surroundings of a local uranium mine show that the impact of Crucea mine on water quality downstream of mining area is insignificant.