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As an important part of the early Mesozoic granites in the South Qinling tectonic belt (SQTB), the Guangtoushan pluton provides a material basis for research on the composition of magma sources and the effects of peritectic assemblage entrainment (PAE) on the changes in the granite composition. As shown by the results of LA‐ICP‐MS zircon U‐Pb dating, the Guangtoushan pluton was emplaced during the Late Triassic (214–212 Ma) and was formed in the post‐collision stage between the SQTB and the Yangtze plate. The collected samples had high SiO2 content and low Cr and Ni contents, indicating that the magmas did not undergo significant crust‐mantle mixing during their evolution. The Guangtoushan granitoids were distributed along the trend line of magmatic fractional crystallization in the F–An–Or diagram. This result, combined with the relatively homogeneous Sr‐Nd isotopic composition, implies that the Guangtoushan pluton underwent slight assimilation and contamination. As can be inferred from the comparison between the compositions of the Guangtoushan granitoids and various fluid‐absent experimental melts, the magma sources of the Guangtoushan granitoids contain a variety of materials, such as graywackes, pyroclastic graywackes, and pelites and are not derived from lower crustal mafic rocks. The correlation between the maficity and the major and trace elements further indicates that the strongly peraluminous granitoids from the Guangtoushan pluton was formed by the partial melting of biotite‐bearing crustal rocks and its magmatic evolution was accompanied by the entrainment of clinopyroxenes and accessory minerals. [ABSTRACT FROM AUTHOR]

Whether a Neoarchean basement existing in the Songnen massif is currently debated. Identification of Archean magmatism from the Songnen Massif is helpful to resolve this issue. Here, we report newly discovered Neoarchean Shanquan pluton in the Western Songnen Massif. These Neoarchean Shanquan pluton are mainly composed of granites that are exposed near the town of Shanquan in Heilongjiang Province. LA‐ICP‐MS zircon U‐Pb dating reveals that the sample 2015TW1 has an upper intercept age of 2801 ± 69 Ma and a weighted mean age of 2708 ± 18 Ma, while samples LJ27QY1 and LJ27QY2 have upper intercept ages of 2677 ± 57 Ma and 2653 ± 18 Ma, and weighted mean ages of 2649 ± 10 Ma and 2653 ± 15 Ma, respectively. This indicates that these granites were formed at ~2.7 Ga. Most of the ~2.7 Ga zircons have older TDM2 ages of 2762–3326 Ma with positive εHf(t) values ranging from 0 to 6.4, while a few of the zircons have negative εHf(t) values ranging from −8.1 to −11.5 and older TDM2 ages varying from 3158 to 3264 Ma. The zircon Hf isotopes indicate that Paleo‐Mesoarchean crusts might once existed in the Songnen Massif, and the studied Neoarchean magmas were principally derived from partial melting of these Paleo‐Mesoarchean ancient crust. Based on the geochronological spectrum of magmatic and detrital zircons, the Songnen, Erguna, Jiamusi, Bureya massifs may have a common basement prior to the Neoproterozoic and may even be linked with the Triam Craton. [ABSTRACT FROM AUTHOR]

A comprehensive study of zircon U‐Pb geochronology, in situ Hf isotopes, whole‐rock major and trace element geochemistry, and Nd isotopes was carried out for two Early Jurassic two‐mica granites (Longtang and Menglong) in the southern part of the Tengchong terrane, which is in the northern part of the larger Sibumasu terrane. We assess the origin of the granites and explore their possible genetic relationship to the Paleo‐Tethyan regime. LA‐ICP‐MS zircon U‐Pb dating shows that they were simultaneously emplaced in the Early Jurassic (ca. 199 Ma). They have SiO2 contents of 69.7–75.1 wt% and are mainly strongly peraluminous with alumina saturation index (ASI) values ranging from 1.06 to 1.46. They show similar Mg# (0.29–0.42) to experimental partial melts of metasedimentary rocks under continental pressure‐temperature (P‐T) conditions. They are enriched in light rare earth elements (LREEs) relative to heavy rare earth elements (HREEs), with moderately negative Eu anomalies and flat HREEs patterns. They show negative εNd(t) values (–9.0 to –12.4) and εHf(t) values (–8.0 to –9.1). Elemental and isotopic data suggest that they most likely to formed by muscovite‐dehydration melting of a metapelitic source at lower temperatures in the range of 700°C to 750°C. The granites might represent a post‐collisional tectonic setting response to Paleo‐Tethyan regime. [ABSTRACT FROM AUTHOR]

The western segment of the Main Tianshan shear zone (MTSZ) branches into three major dextral strike‐slip shear zones in the Borohoro Ranges, northwestern China. Mylonitic rocks within these zones exhibit vertical foliations, subhorizontal lineations, and dextral kinematics. The microstructures and CPO patterns of calcite and quartz in the tectonites suggest shearing at temperatures of 200°C to 500°C or above. The amount of dextral displacement along the zones is less than 100 km. LA‐ICP‐MS U‐Pb dating of zircons from some pre‐kinematic granites gave ages of 364–325 Ma and 316 Ma, and zircons from a syn‐kinematic leucogranite gave an age of 291 Ma. We propose that dextral shearing along the MTSZ started in the earliest Permian. Our data indicate that collision between the Yili and Junggar plates might have finished before 325 Ma or 316 Ma, with a tectonic transformation from 325 Ma to 300 Ma, resulting in intracontinental transpression from 300 Ma or 291 Ma. We suggest that the formation of the Kazakhstan orocline (KO) took place in two stages, with the early stage of bending driven by convergence related to oblique subduction, and the late stage possibly associated with lateral disarticulation as a result of the dextral strike‐slip shear zones. [ABSTRACT FROM AUTHOR]

During the Late Cretaceous in the Eastern Mediterranean, the northern branch of the southern Neotethys was closed by multiple northward subductions. Of these, the most northerly located subduction created the Baskil continental arc at around 82–84 Ma. The more southerly and intra‐oceanic subduction, on the other hand, produced an arc‐basin system, the Yüksekova Complex, as early as the late Cenomanian–early Turonian. The abundant and relatively well‐studied basaltic rocks of this complex were intruded by dykes, sills and small stocks of felsic–intermediate rocks, not previously studied in detail. The intrusives collected from five different localities in the Elazığ region of eastern Turkey are all subalkaline, with low Nb/Y values. Most of them have been chemically classified as rhyodacites/dacites, whereas a small number appear to be andesites. In normal mid‐ocean‐ridge basalt (N‐MORB)‐normalised plots, the intrusives are characterised by relative enrichments in Th and La over Nb, Zr, Hf, Ti and high field strength elements (HREEs), indicating their derivation from a subduction‐modified source. While their relatively high, positive εNd(i) values (+6.4 and +7.2) might suggest a depleted mantle source for their ultimate origin, somewhat radiogenic Pb values indicate a sedimentary contribution to the source of the rocks. The overall geochemical characteristics indicate their generation in an oceanic arc setting. The zircon U‐Pb Laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) data obtained from five felsic‐intermediate rock samples yielded intrusion dates of 80–88 Ma. This suggests that the Elazığ oceanic arc‐related intrusives are slightly younger than those of the Yüksekova arc‐basin system, but coeval with the Baskil continental arc. However, the felsic–intermediate intrusives show different geochemical characteristics (oceanic arc‐type, with a lack of crustal contamination) to those of the Baskil continental arc. This indicates that these two igneous systems are unrelated and likely developed in different tectonic settings. This, in turn, supports a geodynamic model in which the northern strand of the southern Neotethys was consumed by multiple northward subductions. [ABSTRACT FROM AUTHOR]

The article offers a study on a Late Carboniferous back-arc basin basalts from the Chengjisihanshan Formation in the southern West Junggar to determine its formation age and tectonic environment, magma source and petrogenesis. Topics include Laser ablation inductively coupled plasma mass spectrometry zircon U-Pb isotopic dating and in situ zircon Hf isotope analyses; and cocludes he discovery and confirmation of the Late Carboniferous tholeiites m the Chengjisihanshan Formation.

The article offers a study on zircon U-Pb dating of finegrained tonalite in the Jiefangyingzi area of Chifeng from Silurian Badangshan Formation in order to provide petrologic and chronologic constraints in the Jiefangyingzi area, Mongolia. Topics include collection of samples of tonalite for zircon Laser ablation inductively coupled plasma mass spectrometry U-Pb dating in the area; and conclude that there is a Precambrian basement beneath the Bainaimiao arc belt.

The article discusses the uranium-lead (U-Pb) dating of uranium deposit discovered at the Northern Qinling Orogen, a tectonic belt in China. Topics include the mineralization of uranium during the Devonian period, the crystallization age of uraninite, and the use of laser ablation inductively coupled plasma mass spectrometry to analyse uranium deposit. A chart on the U-Pb isotopic dates of uraninite is presented.

The article offers a study on Nb-Ta mineralization age related to granite which was obtained by using Laser ablation inductively coupled plasma mass spectrometry columbite U-Pb dating method which help the understanding of ore-forming processes in Dajishan deposit. Topics include analytical procedures for columbite U-Pb dating which were performed on muscovite albite granite samples; and concludes that mineralization in the Dajishan deposit were related to the Late Jurassic magma movement.

The article presents a study which focuses on the uranium-lead (U-Pb) dating of zircon by laser ablation inductively coupled plasma mass spectrometry on the Guyong Granites from the Tengchong Block, Western Yunnan in China, and its geological significance. The results of the study indicate that Guyong Granites were emplaced during the Late Cretaceous period.

The article focuses on a research paper discussing the geological significance of the Zhuoma copper polymetallic deposit in Geza Arc metallogenic belt in Yunnan Province, China. It discusses the laser ablation?inductively coupled plasma?mass spectrometry (LA-ICP-MS) uranium?lead (U?Pb) dating to determine U-Pb ages of zircon. It also suggest that the band structure development shows the characteristics of magma genesis of zircon.

The article presents a study conducted to analyze the contribution of magmatism to the formation of rare-metal pegmatites such as lithium, niobium and tantalum and provides evidence from zircon uranium-lead (U-Pb) dating in the Kelumute-Jideke Pegmatite field located in Northwestern China. Topics include regional zonation of pegmatite and ore geology, a study of Laser Ablation Inductively Coupled Plasma Mass Spectrometry, and hydrothermal alteration of magmatic zircons.

The article presents a study on geochemistry and geochronology of andesite rock in Langlike copper deposit located in North Qilian Mountain, China. Topics discussed include characteristics of andesite rock such as massive structure and porphyritic structure, geochemical characteristics of andesite rock such as magnesium, and the use of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) zircon uranium-lead (U-Pb) dating tests to conduct the study.