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The Yama fluorite deposit in the Qilian Orogen in NW China is characterized by predominant granitic magmatism and fluorite mineralization. The wall rocks hosting the fluorite-quartz veins in the Yama area consist of the Yama porphyritic syenogranite and the Wulandawu syenogranite. In this study the major and trace element compositions, zircon U-Pb ages, and zircon Hf isotopes and trace element compositions were investigated. Two samples for the Yama porphyritic syenogranite yielded weighted mean [.sup.206]pb/[.sup.238]U zircon ages of 440.7 [+ or -] 4.8 and 447.9 [+ or -] 6.0 Ma, and one sample for the Wulandawu syenogranite yielded a weighted mean [.sup.206]pb/[.sup.238]U zircon age of 441.2 [+ or -]5.0 Ma, all of which indicate a Late Ordovician to Early Silurian crystallization age. Geochemically, both syenogranites are peraluminous, with high alkali contents, low Zr + Nb + Ce + Y contents, relatively low ([K.sub.2]O + [Na.sub.2]O)/CaO ratios, and high Rb/Sr and Rb/Ba ratios, suggesting that they are fractionated S-type granites. They have zircon [[epsilon].sub.Hf](t) values of -14.9 to -4.4 and -12.2 to -4.5, respectively, suggesting that they were derived from the partial melting of pelitic-rich sources within the relatively shallow Paleoproterozoic reworked crust. The detailed geochronological and geochemical data suggest that the studied syenogranites were emplaced in a post-collisional setting related to the closure of the South Qilian Ocean. Finally, they have relatively low quantitative oxygen fugacity values, indicating relatively reduced redox states, but their very low zircon [Ce.sup.4+]/[Ce.sup.3+] ratios, low whole-rock K/Rb ratios, relatively high Nb/Ta ratios, and low Zr/Hf ratios suggest that they are not likely to form important W-Sn deposits and related fluorite deposits. Key words: zircon U-Pb geochronology, petrogenesis, redox state, mineralization potential, syenogranites, Yama area, Introduction The ~350km wide, ~1200km long Qilian Orogen (QLO), which trends northwest-southeast in the northernmost margin of the Tibetan Plateau (Yan et al. 2019b), is traditionally subdivided from north to [...]

The East Kunlun Orogen (EKO) is located in the western part of the Central Asian Orogenic Belt, and it records the Neoproterozoic-Early Devonian tectonic evolution involving the subduction and extinction of the Proto-Tethys Ocean. The Heihaibei granite is located in the South Kunlun belt within EKO. In this study, geochronology, geochemistry, and Hf isotope analysis of Heihaibei monzogranite and granodiorite were carried out. Their LA-ICP-MS zircon U-Pb results yielded ages of 414.1 [+ ou -] 2.0 and 417.8 [+ ou -] 2.0 Ma. The Heihaibei granite is peraluminous (A/CNK = 0.99-1.30), with high alkali contents (7.76-9.14 wt.%) and 10 000 Ga/Al (2.60-3.38), Fe[O.sup.T]/MgO (27.6-49.5), and Y/Nb ratios (1.93-2.93), suggesting that the Heihaibei granite is an [A.sub.2]-type granite. The Heihaibei granite samples have zircon [epsilon]Hf(t) values ranging from-6.3 to-0.3, which suggests that the Early Devonian granite was derived from partial melting of Mesoproterozoic ([T.sub.DM2] = 1797-1415 Ma) crust. When considering data on contemporaneous granites, geochronological and geochemical data for the Heihaibei granite indicate that it was emplaced in a post-collisional extension environment following the closure of the Proto-Tethys Ocean. The Heihaibei granite was formed by extension of the southern subduction accretionary complex as part of the post-collisional setting during the closure of the Proto-Tethys Ocean. Key words: Heihaibei granite, geochemistry, geochronology, zircon Hf isotope, [A.sub.2]-type granite, East Kunlun Orogen L'orogène du Kunlun oriental (OKO) est situé dans la partie occidentale de la ceinture orogénique d'Asie centrale et préserve un registre de l'évolution tectonique du Néoprotérozoïque au Dévonien précoce comprenant la subduction et la disparition de l'océan proto-Téthys. Le granite de Heihaibei est situé dans la ceinture du Kunlun méridionale, dans l'OKO. Une étude géochronologique, géochimique et des isotopes de Hf de monzogranite et de granodiorite de Heihaibei a été réalisée. La datation U-Pb sur zircons par LA-ICP-MS donne des âges de 414,1 [+ ou -] 2,0 Ma et 417,8 [+ ou -] 2,0 Ma. Le granite de Heihaibei est hypera-lumineux (A/CNK = 0,99-1,30), avec de fortes teneurs d'alcalis (7,76-9,14 % en poids) et des rapports 10 000 Ga/Al (2,60-3,38), Fe[O.sup.T]/MgO (27,6-49,5) et Y/Nb (1,93-2,93) élevés, ce qui indiquerait qu'il s'agit d'un granite de type [A.sub.2]. Les échantillons du granite de Heihaibei présentent des valeurs de [epsilon]Hf(t) sur zircons de-6,3 à-0,3 qui indiqueraient que le granite dévonien précoce est dérivé de la fusion partielle de croûte mésoprotérozoïque ([T.sub.DM2] = 1797-1415 Ma). Au vu de données sur des granites du même âge, les données géochronologiques et géochimiques pour le granite de Heihaibei indiquent qu'il a été mis en place dans un milieu d'extension post-collision suivant la fermeture de l'océan proto-Téthys. Le granite de Heihaibei s'est formé par l'extension du complexe accrétionnaire de subduction méridional au sein du milieu post-collision durant la fermeture de l'océan proto-Téthys. [Traduit par la Rédaction] Mots-clés: granite de Heihaibei, géochimie, géochronologie, isotopes de Hf de zircons, granite de type [A.sub.2], orogène du Kunlun oriental, 1. Introduction The East Kunlun Orogen (EKO) is the major component of the Central China Orogenic System and has a complex Precambrian to Cenozoic structural and magmatic history(Jiang et al. [...]

Geodynamic evolution in the late Paleozoic is significant for understanding the final amalgamation of the Central Asian Orogenic Belt (CAOB). No consensus has yet been reached regarding the late Paleozoic geodynamic evolution of the northern Great Xing'an Range (GXR) in northeastern China, the eastern CAOB. Furthermore, late Paleozoic syenogranitediabase dyke association is present in the Xiaokele area in northern GXR. It provides an important opportunity to understand the nature of magmatism and the geodynamic evolution during this period. This paper presents new zircon U-Pb ages, zircon Hf isotopic compositions, and geochemical data of whole rocks for Xiaokele syenogranite and diabase. Zircon U-Pb dating suggests that the Xiaokele syenogranite (292.5 [+ or -] 0.9 Ma) and diabase (298.3 [+ or -] 1.5 Ma) were emplaced during the early Permian. The Xiaokele syenogranites have high Si[O.sub.2] contents, low MgO contents, and enriched zircon [[epsilon].sub.Hf](t) values, suggesting that their primary magma was generated by the partial melting of the juvenile crustal material. The Xiaokele diabases have low Si[O.sub.2] contents, high MgO contents, are enriched in large-ion lithophile elements, depleted in high-field-strength elements, and exhibit enriched zircon [[epsilon].sub.Hf](t) values. They derived from a lithospheric mantle source that had previously been metasomatized by slab-derived fluids. Combined with previous research results, we believe that the continent-continent collision between the Xing'an and Songliao blocks occurred during the late early Carboniferous - early late Carboniferous (330-310 Ma), and the two blocks were transformed into a post-collisional extensional setting during the latest Carboniferous - early Permian. Key words: early Permian, syenogranite, diabase, post-collisional extensional setting, Xiaokele, northern Great Xing'an Range. L'evolution geodynamique au Paleozoique tardif est importante pour la comprehension de l'amalgamation finale de la ceinture orogenique d'Asie centrale (COAC). Aucun consensus n'a encore ete etabli quant a l'evolution geodynamique au Paleozoique tardif du Grand Xing'an (GX) septentrional de l'est de la COAC dans le nord-est de la Chine. En outre, une association d'age paleozoique tardif de syenogranite et de dykes de diabase est presente dans la region de Xiaokele du GX septentrional, qui offre une bonne occasion de mieux comprendre la nature du magmatisme et de l'evolution geodynamique durant cette periode. L'article presente de nouveaux ages U-Pb sur zircons, des donnees sur la composition des isotopes de Hf des zircons et des donnees geochimiques sur roche totale pour le syenogranite et la diabase de Xiaokele. La datation U-Pb sur zircons indiquerait que le syenogranite (292,5 [+ or -] 0,9 Ma) et la diabase (298,3 [+ or -] 1,5 Ma) de Xiaokele ont ete mis en place durant le Permien precoce. Les syenogranites de Xiaokele ont des teneurs elevees en Si[O.sub.2] et faibles MgO et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons, ce qui indiquerait que leur magma primaire est un produit de la fusion partielle de materiau crustal juvenile. Les diabases de Xiaokele ont des teneurs en Si[O.sub.2] faibles et en MgO elevees et sont enrichies en elements lithophiles a grand rayon ionique, appauvries en elements a forte liaison atomique et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons. Elles proviennent d'une source dans le manteau lithospherique ayant prealablement subi un metasomatisme cause par des fluides issus d'une plaque subductee. A la lumiere de ces resultats et de resultats de travaux anterieurs, nous croyons que la collision continent-continent des blocs de Xing'an et de Songliao s'est produite durant l'intervalle du Carbonifere precoce tardif au Carbonifere tardif precoce (330 Ma-310 Ma) et que les deux blocs se sont transformes en un milieu d'extension post-collision durant l'intervalle de la fin du Carbonifere au Permien precoce. [Traduit par la Redaction] Mots-cles: Permien precoce, syenogranite, diabase, milieu d'extension post-collision, Xiaokele, Grand Xing'an septentrional., Introduction The tectonic evolution of orogenic belts is characterized by changes in the associated magmatic composition (Harris et al. 1986). Post-collisional magmatism, as one of the common characteristics of many [...]

The Yama area is characterized by numerous large-scale fluorite–quartz veins that are located along faults within the widespread Late Devonian–Late Silurian syenogranites in the Tataleng granitic batholith, Qilian Orogen, Northwest China. These fluorite–quartz veins contribute to an important fluorite reserve, but their ore genesis remains unresolved so far. In this study, trace elements, rare earth elements (REEs), and hydrogen, oxygen, and strontium isotopic compositions of fluorites are analyzed. The studied fluorite samples have similar chondrite-normalized REEs, including Y patterns, with relatively strong enrichment in heavy REEs, negative Eu anomalies, strongly positive Y anomalies, and comparably invariable Y/Ho ratios of 41.43–73.79, suggesting a unique hydrothermal genesis. The relatively variable values of δD and δ18O are −77.4‰ to −102.4‰ and −12.7‰ to −4.3‰, respectively, close to the meteoric water line. These fluorites yield relatively invariable analytical 87Sr/86Sr ratios of 0.749089−0.756628 (except for an anomalously high ratio), and their calculated initial 87Sr/86Sr ratios, based on the ore-forming ages provided, are apparently higher than the calculated initial 87Sr/86Sr ratios of syenogranite wall rocks. Collectively, the geochemistry of trace elements, REEs, and stable isotopes (H, O, and Sr) suggests that the ore-forming fluids were of meteoric origin and that the Sr sources were directly derived from the ore-forming fluids themselves rather than syenogranite wall rocks. Finally, it was considered that the Yama fluorite deposit is a fault-controlled hydrothermal vein-type deposit which was possibly related to the evolution of the Paleo-Tethys Ocean in the Permian–Triassic. [ABSTRACT FROM AUTHOR]

The Chaqiabeishan area of the Quanji Massif in NW China is characterized by extensive Li‐rich pegmatites and granites of various ages. In this study, the major and trace element compositions, U–Pb zircon ages, and zircon Hf isotopic compositions of the granites were investigated, including the Garideng porphyritic monzogranite, the Gongkaxiuma monzogranite, and the Narong granitic porphyry. Precise U–Pb zircon dating revealed that these three granites were emplaced at approximately 468, 444, and 245 Ma, respectively. The geologic and geochemical data indicate that the Garideng porphyritic monzogranite and the Narong granitic porphyry are two I‐type granites, and the Gongkaxiuma monzogranite is an A2‐type granite. Based on the Hf isotopes and geochemical data, the Garideng porphyritic monzogranite and the Narong granitic porphyry were derived from partial melting of the relatively deep and relatively shallow juvenile mantle‐derived mafic lower crust, respectively, while the Gongkaxiuma monzogranite was derived from partial melting of the granulitic metamorphic basement. Moreover, tectonically, the Garideng porphyritic monzogranite represents the northward subduction of the South Qilian oceanic plate from 500 to 440 Ma. The Gongkaxiuma monzogranite represents the closure of the South Qilian Ocean by ~440 Ma, and the Narong granitic porphyry represents the Late Permian to Middle Triassic southward subduction of the Zongwulong oceanic plate under the Quanji Massif. [ABSTRACT FROM AUTHOR]

Tubal obstructive infertility is one of the most common causes of female infertility. At present, the main treatment is surgical mechanical dredging and restoration of tubal anatomy. Although the success rate of recanalization is high, the postoperative reocclusion rate is also high. In addition to the destruction of fallopian tubal function, it seriously affects the long-term pregnancy rate of women. Therefore, how to reduce the re-adhesion rate after recanalization is a more concerned issue at present. This article reviews the research progress of drug therapy for anti-adhesion after recanalization of tubal obstructive infertility. [ABSTRACT FROM AUTHOR]

Objective: To systematically evaluate the clinical efficacy of Kuntai Capsules combined with Diane-35 in the treatment of polycystic ovarian syndrome (PCOS). Methods: The randomized controlled trials (RCTs) of Kuntai Capsules combined with Diane-35 in the treatment of PCOS from databases establishment to April 2020 were searched in Chinese and English databases, and then meta-analysis was performed using RecMan 5.3 software. Results: A total of 132 articles were collected and 14 studies were included. The total sample size was 1254 cases, including 627 cases in the experimental group and 627 cases in the control group. Meta-analysis showed that the combined group was significantly superior to the single group in terms of overall response rate (OR=5.53,95%CI[3.25,9.41], P<0.01), ovulation rate (OR=3.54,95%CI[2.13,5.88], P<0.01), and pregnancy rate (OR=3.21,95%CI[2.00, 5.14], P<0.01). In terms of serum sex hormone levels, the combined group was significantly better than the singer group for the regulation of follicle-stimulating hormone (FSH) (MD=-2.09,95%CI[-2.16,-2.01],P<0.01), luteinizing hormone (LH) (MD=-2.15,95%CI[-2.35,-1.95],P<0.01), estrogen (E2) (MD=36.47,95%CI[34.97,37.96],P<0.01), and testosterone (T) (MD=-1.95,95%CI[-2.77,-1.14],P<0.01). In addition, the combined group also showed some advantages over the single group in improving the level of insulin resistance (HOMA-IR) and pancreatic beta cells function (HOMA-ß). Conclusion: Kuntai Capsules combined with Diane-35 had certain efficacy advantage in the treatment of PCOS compared with control group. However, the data indicate that the methodological quality of the studies are low, there was potential publication bias, no define conclusion could be drawn, and more high-quality RCTs studies are needed for further validation. [ABSTRACT FROM AUTHOR]

The Hongshuihe area of Eastern Kunlun Orogen is well‐known for the BIF‐type deposits. Some widespread intrusive rocks in the northern Hongshuihe area were previously thought to be emplaced in the Hercynian. This article presents LA‐ICP‐MS zircon U–Pb ages, with LA‐MC‐ICP‐MS in situ Hf isotopes and major and trace element data for quartz diorites and granites of the Hongshuihe pluton. Two samples from the Hongshuihe quartz diorite and granite yielded a weighted mean zircon U–Pb age of 244 ± 2 Ma (Anisian) and 246 ± 1 Ma (Olenekian), respectively. The Hongshuihe subalkaline quartz diorite is metaluminous with the alumina saturation index values of 0.93–1.00, and high SiO2 contents of 59.67–65.51 wt.%, low Y values of 11.1–16.7 ppm, and low HREE (Yb = 1.08–1.83 ppm) that collectively suggest high‐SiO2 adakite‐like rocks. The Hongshuihe granites have slightly high alkali contents of 7.04–8.12 wt.%, alumina saturation index values of 1.01–1.03, low (Zr + Nb + Ce + Y) contents of 315.30–455.50 ppm, and high Fe2O3T/MgO ratios of 4.03–5.16, indicating fractionated I‐type normal island arc magma. The zircon εHf(t) values from −4.0 to −1.1 for the Hongshuihe quartz diorite sample and values from −2.4 to +1.7 for the granite sample correspond to partial melting of Mesoproterozoic thickened lower crust and partial melting of juvenile mantle‐derived mafic lower crust, respectively. We conclude that during the Early–Middle Triassic, the Eastern Kunlun area underwent a tectonic setting of the northward subduction of the Palaeo‐Tethys oceanic slabs. [ABSTRACT FROM AUTHOR]

The Wulonggou area in the Eastern Kunlun Orogen (EKO) in Northwest China is characterized by extensive granitic magmatism, ductile faulting, and orogenic gold mineralizations. The Shidonggou granite is located in the central part of the Wulonggou area. This study investigated the major as well as trace-element compositions, zircon U–Pb dates, and zircon Hf isotopic compositions of the Shidonggou granite. Three Shidonggou granite samples yielded an average U–Pb zircon age of 416 Ma (Late Silurian). The Late Silurian Shidonggou granite is peraluminous, with high alkali contents, high Ga/Al ratios, high (K2O + Na2O)/CaO ratios, and high Fe2O3T/MgO ratios, suggesting an A-type granite. The Shidonggou granite samples have zircon εHf(t) values ranging from −7.1 to +4.4. The Hf isotopic data suggest that the Late Silurian granite was derived from the partial melting of Palaeo- to Mesoproterozoic juvenile mantle-derived mafic lower crust. Detailed geochronological and geochemical data suggest that the Late Silurian granite was emplaced in a post-collisional environment following the closure of the Proto-Tethys Ocean. Combining data of other A-type granitic rocks with ages of Late Early Silurian to Middle Devonian, such post-collisional setting related to the Proto-Tethys Ocean commenced at least as early as ~430 Ma (Late Early Silurian), and sustained up to ~389 Ma (Middle Devonian) in the EKO. [ABSTRACT FROM AUTHOR]