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The Wulong lode gold deposit is located in the Liaoning Province, northeast part of North China Craton. Gold ore bodies are mainly hosted in the Late Jurassic granite and structurally controlled by northeast-trending faults. Gold occurs in disseminated and auriferous quartz-sulfide veins and veinlets within hydrothermally altered rocks. Mineralization can be divided into three stages: (1) quartz-pyrite stage, (2) quartz-polymetallic sulfides stage, and (3) quartz-carbonate stage. Gold formed mainly in the middle stage. Quartz formed in the two earlier stages contains three compositional types of fluid inclusions, i.e., pure C[O.sub.2], C[O.sub.2]--[H.sub.2]O and NaCl--[H.sub.2]O, but the late-stage minerals only contain NaCl--[H.sub.2]O inclusions. The inclusions in quartz formed in the early, main, and late stages yield total homogenization temperatures of 317-383 [degrees]C, 260-380 [degrees]C and 159-234 [degrees]C, respectively, with salinities of 5.14-9.44, 2.95-6.20,1.23-4.34 wt% NaCl equivalent, respectively. Trapping pressures estimated from C[O.sub.2]--[H.sub.2]O inclusions are 200-390 MPa in the main stage. Fluid boiling and immiscibility caused rapid precipitation of sulfides and gold. Through immiscibility and inflow of meteoric water, the ore-forming fluid system evolved from C[O.sub.2]-rich to C[O.sub.2]-poor in composition, and from magmatic to meteoric, as indicated by [[delta].sup.18][O.sub.water] values (4.5[per thousand]-7.3[per thousand]). The carbon (-12.2[per thousand] to -11.5[per thousand]), sulfur (0.9[per thousand]-2.6[per thousand]), and lead isotope ([.sup.207]Pb/[.sup.204]Pb of 15.606-15.618) compositions suggest the host rocks to be a significant source of ore metals. Integrating the data obtained from the studies including regional geology, ore geology, fluid inclusion, and C--H--O--S--Pb isotope geochemistry, we conclude that the Wulong deposit is a decratonization gold deposit formed during lithospheric thinning associated with destruction of the North China Craton triggered by the subduction of the Paleo-Pacific Oceanic plate in the Early Cretaceous. Key words: Wulong lode gold deposit, C--H--O--S--Pb isotopes, fluid inclusions, northeastern North China Craton, decratonization-type gold deposit. Le gisement d'or filonien de Wulong est situé dans la province de Liaoning, dans la partie nord-est du craton de Chine septentrionale. Les corps aurifères sont principalement encaissés dans du granite d'âge jurassique tardif et sont contrôlés sur le plan structural par des failles d'orientation nordest. L'or se trouve dans des filons et filonnets de quartz--sulfures aurifères disséminés dans des roches ayant fait l'objet d'une altération hydrothermale. La genèse de la minéralisation peut être divisée en trois étapes : (1) une étape à quartz et pyrite, (2) une étape à quartz et sulfures polymétalliques et (3) une étape à quartz et carbonates. L'or s'est principalement formé durant la deuxième étape. Le quartz formé durant les deux premières étapes contient trois types d'inclusions fluides sur le plan compositionnel, à savoir des inclusions de C[O.sub.2] pur, de C[O.sub.2]--[H.sub.2]O et de NaCl--[H.sub.2]O, alors que les minéraux de la dernière étape ne contiennent que des inclusions de NaCl--[H.sub.2]O. Les inclusions dans le quartz formées durant les étapes précoce, principale et tardive donnent des températures d'homogénéisation totale de 317-383 [degré]C, 260-380 [degré]C et 159-234 [degré]C, respectivement, et des salinités de 5,14-9,44%, 2,95-6,20% et 1,23-4,34% en poids d'équivalent NaCl, respectivement. Les pressions de piégeage estimées pour les inclusions de C[O.sub.2]--[H.sub.2]O sont de 200-390 MPa durant l'étape principale. L'ébullition et l'immiscibilité des fluides ont entraîné la précipitation rapide de sulfures et d'or. En raison de l'immiscibilité et de l'entrée d'eau météorique, le système de fluides minéralisateurs est passé d'une composition riche en C[O.sub.2] à une composition pauvre en C[O.sub.2], et de magmatique à météorique, comme l'indiquent les valeurs de [[delta].sup.18][O.sub.eau] (4,5 [per thousand]-7,3 [per thousand]). Les concentrations d'isotopes de carbone (de -12,2 [per thousand] à -11,5 [per thousand]), de soufre (0,9 [per thousand]-2,6 [per thousand]) et de plomb ([.sup.207]Pb/[.sup.204]Pb : 15,606-15,618) donnent à penser que les encaissantes étaient une importante source des métaux composant le minerai. L'intégration des données obtenues des études de la géologie régionale, de la géologie du minerai, des inclusions fluides et de la géochimie des isotopes de C--H--O--S--Pb nous permet de conclure que le gisement de Wulong est un gisement aurifère de type décratonisation, formé durant l'amincissement de la lithosphère associé à la destruction du craton de Chine septentrionale déclenchée par la subduction de la plaque océanique paléopacifique au Crétacé précoce. Mots-clés: gisement d'or filonien de Wulong, isotopes de C--H--O--S--Pb, inclusions fluides, nord-est du craton de Chine septentrionale, gisement aurifère de type décratonisation., Introduction The concept of an orogenic-type gold deposit was first introduced by Bohlke (1982) and then thoroughly addressed by Groves et al. (1998), Kerrich et al. (2000), and Goldfarb et [...]

To prepare air filtration materials with antibacterial properties, PSF nanofibrous membranes were prepared by electrospinning method. Polysulfone (PSF) was used as solute, N, N-dimethylformamide (DMF) and l-methyl-2-pyrrolidone (NMP) were used as solvent, and then zinc oxide (ZnO) films were magnetron sputtered on the surface of the prepared PSF nanofibrous membranes. Finally, the PSF/ZIF8 nanofibrous membranes were obtained by converting ZnO film into zeolitic imidazolate framework-8 (ZIF8) crystals after the hydrothermal process. The physical and chemical properties, filtration properties, air permeability, antibacterial and bacterial filtration properties of the obtained composite membranes were tested subsequently. The results show that the filtration efficiency of PSF/ZIF8 nanofibrous membranes can reach 99. 82% for PM0.3. The high porosity of the nanofibrous membranes results in a high air permeability (340. 36 mm • s-1). In addition, the composite membrane has certain antibacterial properties against Staphylococcus aureus and Escherichia coli, and the interception efficiency against both bacteria reaches 99. 99%. [ABSTRACT FROM AUTHOR]

The Meiling Cu‐polymetallic deposit is located in the Kalatag Cu metallogenic belt of the East Tianshan, Xinjiang, NW China. Multiple‐stage hydrothermal activities have resulted in the silicification, chlorite alteration and sericite alteration in this deposit. At least three mineralization stages are recorded: (a) a phase comprising quartz–pyrite veining, (b) a quartz–chalcopyrite–pyrite–sphalerite phase and (c) a quartz–calcite phase, respectively. LA–ICP–MS zircon U–Pb dating yielded 302 ± 2.1 Ma for an ore‐bearing quartz porphyry and 296 ± 3.2 Ma for a post‐mineralization diorite porphyry dyke, respectively, indicating that the copper mineralization took place during the Late Carboniferous period (302–296 Ma). Fluid evolution during the three stages of mineralization was determined by a detailed fluid inclusion study: (a) Stage I fluids were trapped under two‐phase conditions, as evidenced by the coexistence of vapour‐rich (type II) inclusions (Th = 183–242°C, average salinity = 4.8 wt% NaCl equiv.), liquid‐rich (type I) inclusions (Th = 171–259°C, average salinity = 5.3 wt% NaCl equiv.), and daughter‐bearing (type III) inclusions (Th = 192–208°C, average salinity = 8.6 wt% NaCl equiv.). (b) Stage II fluid inclusions in quartz were also trapped under two‐phase conditions (boiling), as identified by the coexistence of V‐ and L‐type fluid inclusions; L‐type inclusions Th between 136 and 218°C (average = 189°C), with salinities of 2.2–7.6 wt% NaCl equiv. (average = 3.8 wt% NaCl equiv.). V‐type inclusions homogenized temperatures between 153 and 226°C (average = 192°C), with salinities of 2.4–6.7 wt% NaCl equiv. (average = 3.5 wt% NaCl equiv.). (c) Stage III fluids are represented by inclusions in barren quartz–carbonate veinlets, characterized by homogenization temperatures ranging from 98 to 177°C (average = 135°C) and salinities between 0.5 and 3.2 wt% NaCl equiv. (average = 1.9 wt% NaCl equiv.). The initial hydrothermal fluids are characterized by low–intermediate temperature, low‐salinity and near‐neutral pH condition, belonging to a H2O–NaCl bearing hydrothermal system. The mineralization of the Meiling deposit occurred at a shallow crustal level (~0.5 km), and the decrease of temperature was likely an important factor responsible for metal accumulation and deposition in the subvolcanic hydrothermal system. [ABSTRACT FROM AUTHOR]

The Xiaojiashan tungsten deposit is located about 200 km northwest of Hami City, the Eastern Tianshan orogenic belt, Xinjiang, northwestern China, and is a quartz vein‐type tungsten deposit. Combined fluid inclusion microthermometry, host rock geochemistry, and H–O isotopic compositions are used to constrain the ore genesis and tectonic setting of the Xiaojiashan tungsten deposit. The orebodies occur in granite intrusions adjacent to the metamorphic crystal tuff, which consists of the second lithological section of the first Sub‐Formation of the Dananhu Formation (D2d12). Biotite granite is the most widely distributed intrusive bodies in the Xiaojiashan tungsten deposit. Altered diorite and metamorphic crystal tuff are the main surrounding rocks. The granite belongs to peraluminous A‐type granite with high potassic calc‐alkaline series, and all rocks show light Rare Earth Element (REE)‐enriched patterns. The trace element characters suggest that crystallization differentiation might even occur in the diagenetic process. The granite belongs to postcollisional extension granite, and the rocks formed in an extensional tectonic environment, which might result from magma activity in such an extensional tectonic environment. Tungsten‐bearing quartz veins are divided into gray quartz vein and white quartz veins. Based on petrography observation, fluid inclusions in both kinds of vein quartz are mainly aqueous inclusions. Microthermometry shows that gray quartz veins have 143–354°C of Th, and white quartz veins have 154–312°C of Th. The laser‐Raman test shows that CO2 is found in fluid inclusions of the tungsten‐bearing quartz veins. Quadrupole mass spectrometry reveals that fluid inclusions contain major vapor‐phase contents of CO2, H2O. Meanwhile, fluid inclusions contain major liquid‐phase contents of Cl−, Na+. It can be speculated that the ore‐forming fluid of the Xiaojiashan tungsten deposit is characterized by an H2O–CO2, low salinity, and H2O–CO2–NaCl system. The range of hydrogen and oxygen isotope compositions indicated that the ore‐forming fluids of the tungsten deposit were mainly magmatic water. The ore‐forming age of the Xiaojiashan deposit should to be ~227 Ma. During the ore‐forming process, the magmatic water had separated from magmatic intrusions, and the ore‐bearing complex was taken to a portion where tungsten‐bearing ores could be mineralized. The magmatic fluid was mixed by meteoric water in the late stage. The Xiaojiashan tungsten deposit is located about 200 km northwest of Hami City, Eastern Tianshan orogenic belt, Xinjiang, northwestern China and is a quartz vein‐type tungsten deposit. In this contribution, we report new results obtained from ore geology research, fluid inclusion and H–O stable studies for the Xiaojiashan deposit. [ABSTRACT FROM AUTHOR]