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The Cenozoic geological hallmark of Western Yunnan is the characteristic voluminous Late Cretaceous‐Eocene granites; however, their geological background and petrogenesis have not been well constrained and elucidated. In this study, we present new zircon U‐Pb dating, along with geochemical and Sr‐Nd‐Hf isotopic data for granites from the Tengchong–Lianghe granitoid belt (as abbreviated to Tengliang belt) and West Yingjiang batholiths from the Tengchong block. The mineralogical and geochemical features of the Tengliang granites and the West Yingjiang batholiths are ascribed to aluminous S‐type granites and weak peraluminous I‐type, respectively. Zircon U‐Pb analyses yielded consistent ages ranging from 67.5 Ma, 68.4 Ma and 66.2 Ma from the Tengliang granitoid belt and 50.4 Ma to 60.8 Ma for three samples from the west Yingjiang batholiths. The Tengliang granites were emplaced during the Late Cretaceous (68–66 Ma) and demonstrate negative εHf(t) values (–24 to –4) and initial 87Sr/86Sr ratios of 0.7101–0.7139 and significant negative εNd(t) values from –8.91 to –13.2, indicating a Proterozoic sedimentary source or enriched components. The hornblende‐bearing I‐type granites from West Yingjiang are characterized by lower initial 87Sr/86Sr ratios of 0.7076–0.7106, compared to Tengliang granite and negative whole‐rock εNd(t) values from –4.0 to –11.9. The early Eocene west Yingjiang gneissic granites show wide ranges of εHf(t) values from +7.4 to –8.5 and T2DM of 1.30–0.65 Ga, indicating partial melting of ancient crust with contributions of depleted mantle materials. In combination with the regional background and previous studies, we propose that such a spatio‐temporal distribution of the Tengchong granitoid belt might be related to the rollback or angle‐switching of the Neo‐Tethyan subducting slab. This study sheds new light on the evolutionary history of the Tengchong block. [ABSTRACT FROM AUTHOR]

Investigation of the petrogenesis and the origin of zircons from the volcanic rocks of the Liujiaping Group of the back-Longmenshan tectonic belt in the northwest margin of the Yangtze Block is conducted by analysis of U-Pb geochronology and geochemistry. Results show that selected zircons are characterized by internal oscillatory zonings and high Th/U ratios (0.43-1.18), indicating an igneous origin. Geochronological results of LA-ICP-MS U-Pb dating of the Liujiaping Group zircons yield an age of 809 ± 11 Ma (MSWD = 2.2), implying that the volcanic rocks were formed in the Late Neoproterozoic. Geochemical analysis shows that the rocks are calc-alkaline, supersaturated in Al, and metaluminous to weakly peraluminous. Rare-earth elements are present at high concentrations (96.04-265.48 ppm) and show a rightward incline and a moderately negative Eu anomaly, similar to that of continental rift rhyolite. Trace element geochemistry is characterized by evident negative anomalies of Nb, Ta, P, Th, Ti, inter alia, and strong negative anomalies of K, Rb, Sr, et al. We conclude that the Liujiaping Group volcanic rocks resulted from typical continental crust source petrogenesis and were formed in a continental margin setting, which had no relation to subduction, and thus, were the products of partial melting of the lower crust due to crustal thickening caused by active continental margin subduction and arc-continent collision orogeny in the northwestern Yangtze Block and were triggered by the breakup of the Rodinia supercontinent during the Neoproterozoic. [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]

The article presents a study which discusses petrogenesis and significance the Jebel Dumbier Alkaline-carbonatite complex from North Margin of Nuba Mountains, Sudan. the genetic relationships of the fluorite, carbonatite and distinct syenitic rocks, appearance of ditroite, and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) zircon dating results.

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.