Chronological study advances of the granites and uranium mineralization in the Changjiang uranium ore-field
1. School of Earth Science,East China University of Technology,Nanchang 330013,China 2. Key Laboratory of Airborne Geophysics and Remote Sensing Geology,MNR,Beijing 100083,China 3. China Aero Geophysical Survey and Remote Sensing Center for Natural Resources,Beijing 100083,China
The Changjiang uranium ore field is located in the south-central part of the Zhuguangshan pluton in northern Guangdong Province. This ore field holds many uranium deposits such as Mianhuakeng (302), Shulouqiu (305), and Changpai. These uranium deposits are mainly distributed along the contact parts between the Changjiang and Youdong plutons, and uranium mineralization is closely related to the Changjiang and Youdong plutons and their intrusive dykes. Previous researchers have conducted much testing on the formation ages of plutons, dykes, and deposits in the Changjiang ore field, obtaining abundant age data. This study summarized the chronological study advances of the granites, uranium mineralization, and dykes in the Changjiang uranium ore field. The results are as follows. The Changjiang biotite granite pluton was formed at 166~157 Ma (weighted average age: 160.9 Ma) during the Middle-Late Jurassic. The Youdong two-mica granite pluton was formed at 245.6~219.6 Ma (weighted average age: 232.1 Ma) during the Triassic. A variety of dykes such as gabbro diorites, hornblende diabases, fine-grained granitic rocks, and lamprophyres have developed in the study area. The dykes in the ore field can be divided into at least three categories according to their activity stages, namely Late Jurassic mafic dykes (150~145.1 Ma), Early Cretaceous acid dykes (138.6~123.9 Ma), and Early Cretaceous mafic dykes (110 Ma). The uranium mineralization of the Changjiang uranium ore field began during the Early Cretaceous and lasted until the Paleocene, showing a long time span ranging from 127 to 60 Ma. The uranium metallogenic periods include the Early Cretaceous metallogenic epoch (127~119 Ma), the Late Cretaceous metallogenic epoch (75~67 Ma), and the Paleocene metallogenic epoch (61~54 Ma). The age data are concentrated in the range of 70~60 Ma (Late Cretaceous-Paleocene), which might be the peak of uranium mineralization of the study area. The diagenesis and uranium mineralization of the Changjiang uranium ore field evolved in the order of Youdong pluton → Changjiang pluton → early mafic dykes → fine-grained granitic dykes → early uranium mineralization stage → fine-grained biotite granite dykes → late mafic dykes → second uranium mineralization stage → late uranium mineralization stage. There are six phases of diagenesis and uranium mineralization of the Changjiang uranium ore field, i.e., Triassic granitic magmatism (the Youdong pluton), Middle-Late Jurassic granitic magmatism (the Changjiang pluton), diagenesis of Late Jurassic mafic dykes (gabbro diorite dykes, 150 Ma; hornblende diabase dykes, 145 Ma), diagenesis of Early Cretaceous dykes and uranium mineralization (138.6~110 Ma), Late Cretaceous uranium mineralization (75~67 Ma), and Paleocene uranium mineralization (61~54 Ma). It is recommended that further studies should be conducted on the metallogenic chronology of uranium deposits, the geochronology of other dykes such as lamprophyres, and the uranium metallogenic mechanisms of deposits except for Mianhuakeng (302), Shulouqiu(305), and Changpai.
朱卫平. 长江铀矿田花岗岩与铀成矿年代学研究进展[J]. 物探与化探, 2022, 46(6): 1327-1337.
ZHU Wei-Ping. Chronological study advances of the granites and uranium mineralization in the Changjiang uranium ore-field. Geophysical and Geochemical Exploration, 2022, 46(6): 1327-1337.
Wang K X, Sun L Q, Sun T, et al. Provenance, weathering conditions, and tectonic evolution history of the Cambrian meta-sediments in the Zhuguangshan area, Cathaysia Block[J]. Precambrian Research, 2018, 311:195-210.
Zhang W M, Yan J, Zhong F J, et al. In situ LA-ICP-MS U-Pb dating of uraninite from the Shijiaowei granite-type uranium deposit,northern Guangdong Province[J]. Rock and Mineral Analysis, 2019, 38(4): 449-460.
Zhang L, Chen Z Y, Wang F Y, et al. Apatite geochemistry as an indicator of petrogenesis and uranium fertility of granites: A case study from the Zhuguangshan batholith, South China[J]. Ore Geology Reviews, 2021, 128:1-15.
Zhang L, Chen Z Y, Li X F, et al. Zircon U-Pb geochronology and geochemistry of granites in the Zhuguangshan complex,South China:Implications for uranium mineralization[J]. Lithos, 2018,308-309:19-33.
Zhong F J, Pan J Y, Wu J H, et al. Petrogenesis and its relationship with uranium mineralization of gabbro-diorite in Changjiang uranium ore-field,northern Guangdong Province,China[J]. Earth Science, 2019, 44(9):3042-3059.
Zhong F J. Petrogensis and mineralization of granite type uranium deposits in South China:A case study of the Changjiang uranium ore field in northern Guangdong Province[D]. Nanchang: East China University of Technology, 2018.
Chen Y, Pan J Y, Zhong F J, et al. U-Pb isotopic dating of granite monazite and its geological significance from the Changjiang uranium ore field,northern Guangdong Province[J]. Rock and Mineral Analysis, 2022, 41(1):1-13.
张敏. 粤北产铀岩体的年代学和地球化学及铀成矿机制研究[D]. 南京: 南京大学, 2006.
Zhang M. Geochronology, geochemistry and uranium metallogenic mechanism of uranium in northern Guangdong[D]. Nanjing: Nanjing University, 2006.
Cao H J, Huang G L, Xu L L, et al. The Ar-Ar age and geochemical characteristics of diabase dykes of the Youdong fault zone in south of Zhuguang granites pluton[J]. Acta Geologica Sinia, 2013, 87(7):957-966.
Xu W X, Tan Z Y, Luo C W, et al. Geochemical characteristic and ore-forming geological significance of fine crystalline in Mianhuakeng uranium deposit,northern Guangdong[J]. Uranium Geology, 2014, 30(6):345-355.
Zhou H B, Pan J Y, Zhong F J, et al. Genesis of fine grained biotite granite in the Changjiang uranium ore field,northern Guangdong of China,and its relation with uranium mineralization[J]. Journal of Mineralogis and Petrology, 2018, 38(1):10-19.
Zhong F J, Yan J, Xia F, et al. In-situ U-Pb isotope geochronology of uraninite for Changjiang granite-type uranium ore field in northern Guangdong,China: Implications for uranium mineralization[J]. Acta Petrologica Sinica, 2019b, 35(9):2727-2744.
Zheng G D, Luo Q, Liu W Q, et al. In-situ U-Pb age and elemental characteristics of the pitchblende in the Shulouqiu uranium deposit and its geological significance[J]. Earth Science, 2021, 46(6):2172-2186.
Zhang A, Liu C D, Yu Z L, et al. The features and geochronology of alkali metasomatic rock in southern Zhuguang uranium mineralization area[J]. Journal of East China Universtiy of Technology, 2009, 32(3):209-212.
Huang G L, Yin Z P, Ling H F, et al. Foration age,geochemical characteris ticas and genesis of pitchblende from No.302 uranium deposit in northern Guangdong[J]. Mineral Deposits, 2010, 29(2):352-360.
Christophe B, Liu X D, Julien M, et al. The genesis of granite-related hydrothermal uranium deposits in the Xiazhuang[J]. Ore Geology Reviews, 2018(92):588-612.
Zhong F J, Pan J Y, Qi J M, et al. New in-situ LA-ICP-MS U-Pb ages of uraninite from the Mianhuakeng uranium deposit,northern Guangdong Province,China: Constraint on the metallogenic mechanism[J]. Acta Geologica Sinica:English Edition, 2018, 92(2):852-854.
Yu Y S, Dai P Y, Guo F S, et al. Genesis and age of Fuxi granodiorite Southern Zhuguang mountain,northern Guangdong Province:Constrain from mineralogy chemistry,geochemistry and LA-ICP-MS Zircon U-Pb dation[J]. Geological Science and Tecnology Information, 2017, 36(6):71-82.
Luo J C, Qi Y Q, Wang L X, et al. Ar-Ar dating of mafic dykes from the Xiazhuang uranium ore field in northern Guangdong,South China: A reevaluation of the role of mafic dyke in uranium mineralization[J]. Acta Petrologica Sinica, 2019, 35(9):2660-2678.
Ceng T, Li X W, Tao J H, et al. Geochronology, geochemistry and zircon Hf isotope for Banshi and Caifang volcanic rocks from Southern Jiangxi Province and their geological implications[J]. Geotectonica et Metallogenia, 2017, 41(5):933-949.
Hu R Z, Bi X W, Peng J T, et al. Some problems concerning relationship between Mesozoic-Cenozoic lithospheric extension and uranium metallo-genesis in South China[J]. Mineral Deposits, 2007, 26(2):139-152.
Wang J S, Peng L N, Zhang N. Research progress on matrix effects in zircon U-Pb isotopic dating by LA-ICP-MS[J]. Physical Testing and Chemical Analysis Part B:Chemical analysis, 2017, 53(6):736-744.
Zhao K D, Jiang S Y, Ling H F, et al. Reliability of LA-ICP-MS U-Pb dating of zircons with high U concentrations: A case study from the U-bearing Douzhashan Granite in South China[J]. Chemical Geology, 2014, 389:110-121.
Zamyatin D A, Shchapova Y V, Votyakov S L, et al. Alteration and chemical U-Th-total Pb dating of heterogeneous high-uranium zircon from a pegmatite from the Aduiskii massif,middle Urals,Russia[J]. Miner Petrol, 2017, 111:475-497.