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It is unclear whether the South China blocks have an affinity with continental Gondwana due to a lack of direct Pan‐African magmatic and metamorphic features. In this study, we conducted U‐Pb geochronological and Lu‐Hf isotopic analyses for detrital zircons from a sandstone of the Chang'an Formation of the Nanhua Group in the Longsheng region of northern Guangxi, with the aim of constraining the timing of sedimentation and information as to its source, as well as seeking evidence for Pan‐African events in the South China blocks. The results show that the ages of detrital zircons peaked at 654.7 ± 6.2 Ma, 773.2 ± 4.1 Ma and 821.9 ± 6.5 Ma, with some at 920–870 Ma; the youngest age indicates the existence of the Pan‐African thermal event. The ∊Hf(t) and TDM2 values demonstrate that the study area has experienced three stages of crustal growth at 3.0–2.4 Ga, 2.1–1.5 Ga and 1.3–0.9 Ga. With intensively distributed Neoproterozoic mafic‐ultramafic and granitic plutons emplaced at 830–810 Ma along the southwestern section of the Jiangnan Orogenic Belt and positive ∊Hf(t) values from a large group of zircon grains, it is proposed that the sediments of the Chang'an Formation (of Nanhua Group) were largely sourced from the southeastern margin of the Yangtze block. Comparison with the zircon age spectra of the Cathaysian block shows that about 79% of the Pan‐African aged detrital zircon grains that have TDM2 = 1352–1031 Ma and ∊Hf(t) = 3.68–8.79, were sourced from the recycled Grenvillian crust of the Cathaysian block, suggesting that the Cathaysian block had a close connection with Gondwana. [ABSTRACT FROM AUTHOR]

The eastern Hexi Corridor, northwest China, is located at the tectonic junction of the Alxa Block, the North China Craton, and the Qinling‐Qilian Orogen. The early Paleozoic Xiangshan Group record critical information regarding paleoenvironment, paleoclimate and paleotectonic setting, from which we here present a focused study on the chert beds within the Xiangshan Group. Through field mapping, microstructural observation, whole‐rock geochemistry analyses and detrital zircon dating, we suggest that the Xiangshan Group chert was deposited along a passive continental margin, formed primarily through biological activity with minor hydrothermal influence and terrestrial input. The characteristics of the chert support a low latitude sedimentary paleoenvironmental origin, and reveal the fact that the Alxa Block was separated from the North China craton, while emerged some paleogeographic affinity with the Qilian region in the Middle‐Late Cambrian. [ABSTRACT FROM AUTHOR]

The Baleigong granites, located in the western part of the southwestern Tianshan Orogen (Kokshanyan region, China), records late Paleozoic magmatism during the late stages of convergence between the Tarim Block and the Central Tianshan Arc Terrane. We performed a detailed geochronological and geochemical study of the Baleigong granites to better constrain the nature of collisional processes in the Southwest Tianshan Orogen. The LA‐ICP‐MS U‐Pb zircon isotopic analyses indicate that magmatism commenced in the early Permian (∼282 Ma). The granite samples, which are characterized by high contents of SiO2 (67.68–69.77 wt%) and Al2O3 (13.93–14.76 wt%), are alkali‐rich and Mg‐poor, corresponding to the high‐K calc‐alkaline series. The aluminum saturation index (A/CNK) ranges from 0.93 to 1.02, indicating a metaluminous to slightly peraluminous composition. Trace element geochemistry shows depletions in Nb, Ta, and Ti, a moderately negative Eu anomaly (δEu=0.40–0.56), enrichment in LREE, and depletion in HREE ((La/Yb)N=7.46–11.78). These geochemical signatures are characteristic of an I‐type granite generated from partial melting of a magmatic arc. The I‐type nature of the Baleigong granites is also supported by the main mafic minerals being Fe‐rich calcic hornblende and biotite. We suggest that the high‐K, calc‐alkaline I‐type granitic magmatism was generated by partial melting of the continental crust, possibly triggered by underplating by basaltic magma. These conditions were likely achieved in a collisional tectonic setting, thus supporting the suggestion that closure of the South Tianshan Ocean was completed prior to the Permian and was followed (in the late Paleozoic) by collision between the Tarim Block and the Central Tianshan Arc Terrane. [ABSTRACT FROM AUTHOR]

Abstract: We report here U‐Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5–225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma (Norian‐Rhaetian), including three predominant groups of 220–225 Ma, 210–217 Ma and 201–205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive εHf(t) value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1–1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin. [ABSTRACT FROM AUTHOR]

Albitite often accompanies with various metal and gem mineral deposits and a large number of occurrences have been reported globally, including the South Qinling orogen, China. The Xiaozhen copper deposit is a typical deposit in the North Daba Mountain area of the South Qinling orogen whose distribution is controlled by albitite veins and fractures. As there are few studies on the petrogenesis of albitite in Xiaozhen copper deposit, this paper focuses on the petrogenesis of albitite and its mineralization age. Detailed fieldwork and mineral microscopic observations initially suggest that albitite from the Xiaozhen copper deposit is igneous in origin. Further zircon trace element geochemistry studies indicate that these zircons have high Th/U ratios (>0.5), low La content, high (Sm/La)N and Ce/Ce* values, and a strong negative Eu anomaly, which are commonly seen in magmatic zircons. The chondrite-normalized rare earth element (REE) patterns are consistent with magmatic zircons from throughout the world, and they fall within or near the field of magmatic zircons on discriminant diagrams. The calculated average apparent Ti-in-zircon temperature for young zircons is 780°C, consistent with magmatic zircon crystallization temperatures. Therefore, zircon geochemistry indicates that the albitite origin is magmatic. SIMS U-Pb dating on nine magmatic zircons yielded a concordia age of 154.8±2.2 Ma, which represents the formation of albitite and the metallogenic age. More importantly, it is consistent with the ages of Yanshanian magmatism and metallogenesis in the South Qinling orogen, so formation of the Xiaozhen copper deposit may be a closely related geological event. [ABSTRACT FROM AUTHOR]

U-Pb zircon age, geochemical, and Sr-Nd-Pb isotopic data of mafic dykes from eastern Shandong Province, eastern China is reported herein. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb zircon analyses of two samples from the investigated mafic dykes yield consistent ages ranging from 121.9 Ma ± 0.47 Ma to 122.9 Ma ± 0.61 Ma. The mafic dykes are characterized by high (87Sr/86Sr)i ranging from 0.7087 to 0.7089, low εNd( t) values ranging from −16.9 to −17.8, 206Pb/204Pb = 17.15 to 17.17, 207Pb/204Pb = 15.45 to 15.47, and 208Pb/204Pb = 37.59 to 37.68. Results from the current study suggest that the mafic dykes are derived from partial melting of ancient lithospheric mantle that was variably hybridized by melts derived from foundered lower crustal eclogite. The mafic dykes may have been generated through subsequent insignificant crystal fractionation and very minor crustal contamination during magma ascent. Combined with previous studies, the current findings provide new evidence that the intense lithospheric thinning beneath the eastern Shandong Province of eastern China occurred at ∼120 Ma, and that this condition was caused by the removal of the lower lithosphere (mantle and lower crust). [ABSTRACT FROM AUTHOR]

The article provides information on the study conducted in the Bohai Bay Basin (BBB) to determine the geology of the basement rocks including the separation and imaging of zircon crystals using cathodoluminescence (CL). Particular focus is given to the results of the study including the presence of tonalite, oscillatory zoning, and magmatic zircons of the same age. Also discussed is the magmatism in North China Craton (NCC).

The article reports that a new discovery of a 1.8 Ga Erlongshan monzonitic granite has been done on the Western Margin of the Songnen Masiff, China. It mention about the samples of zircon dating geochemical testing have been collected. It states about the characteristics of the zircon crystals related to their color and texture.

The article focuses on a research paper discussing the petrogenesis and geology of the Gangdese porphyry copper deposits in the Tibetan-Himalayan orogen. It analyzes the hafnium-oxygen (Hf-O) isotopes in zircon of the deposit to determine the generation of copper deposits. It also suggest that the mantle component plays an important role in forming giant ore deposits.

The article focuses on a study that investigates geochronology and characteristics of fluid inclusion in the Jinchang deposit in Hainan province, China and their geological significances. The study reveals that ore-forming fluid of the gold deposit were derived from magmatic water mixed with meteoric water during the ore-process. Also discussed is the result of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) analysis zircons from the wall rocks of ore in the deposits.

The article discusses the research study to examine the evolution of granitic magmas and implications for Molybdenum (Mo) deposit formation within the Luanchuan Metallogenic Belt, Eastern Qinling Orogen, Central China. Topics discussed include Zircon Uranium (U)? lead (Pb) dating of lithologically distinct plutons, Pb isotope compositions of pyrites that were coprecipitated with molybdenite, and multiple stages of magmatic evolution.

The article presents a study on uranium?lead (U-Pb) dating and laser ablation?inductively coupled plasma?mass spectrometry (LA-ICP-MS) of Middle Permian granite of Langshan Mountain, China and its indicating significance. Topics discussed include characteristics of granite such as finegrained texture and massive structure; chemical composition of granite and selection of zircon to carry on LA-ICP-MS U-Pb dating.