Petrogenesis of Triassic granite from the Jintan pluton in Central Jiangxi Province, South China: implication for uranium enrichment

Dictynidae spiders were collected from Jinggang Mountain National Nature Reserve, Jiangxi Province, China in the past four years. Five new species are described and illustrated with photographs, SEMs and line drawings: Lathys adunca Liu spec. nov. (male), L. deltoidea Liu spec. nov. (female), L. fibulata Liu spec. nov. (female), L. huangyangjieensis Liu spec. nov. (male, female) and L. zhanfengi Liu spec. nov. (female). Both sexes of the species L. spiralis Zhang, Hu & Zhang, 2012 were collected from leaf litter in Jinggangshan University and the male is described for the first time. All specimens are deposited in the Animal Specimen Museum, Life Science College, at the Jinggangshan University (ASM-JGSU).

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Comparison of Magma Oxygen Fugacity and Zircon Hf Isotopes between Xianglushan Tungsten-Bearing Granite and Late Yanshanian Granites in Jiangxi Province, South China

Minerals ◽

10.3390/min10020106 ◽

2020 ◽

Vol 10 (2) ◽

pp. 106

Author(s):

Xing-Yuan Li ◽

Jing-Ru Zhang ◽

Chun-Kit Lai

Keyword(s):

Oxygen Fugacity ◽

South China ◽

Granitic Magma ◽

Geochemical Data ◽

Jiangxi Province ◽

Magmatic Zircon ◽

Late Mesozoic ◽

Icp Ms ◽

T Values ◽

Southern Jiangxi Province

Jiangxi Province (South China) is one of the world’s top tungsten (W) mineral provinces. In this paper, we present a new LA-ICP-MS zircon U-Pb age and Hf isotope data on the W ore-related Xianglushan granite in northern Jiangxi Province. The magmatic zircon grains (with high Th/U values) yielded an early Cretaceous weighted mean U-Pb age of 125 ± 1 Ma (MSWD = 2.5, 2σ). Zircon εHf(t) values of the Xianglushan granite are higher (−6.9 to −4.1, avg. −5.4 ± 0.7) than those of the W ore-related Xihuanshan granite in southern Jiangxi Province (−14.9 to −11.2, avg. −12.5 ± 0.9), implying different sources between the W ore-forming magmas in the northern and southern Jiangxi Province. Compiling published zircon geochemical data, the oxygen fugacity (fO2) of the late Yanshanian granitic magmas in Jiangxi Province (the Xianglushan, Ehu, Dahutang, and Xihuashan plutons) were calculated by different interpolation methods. As opposed to the W ore-barren Ehu granitic magma, the low fO2 of the Xianglushan granitic magma may have caused W enrichment and mineralization, whilst high fO2 may have led to the coexistence of Cu and W mineralization in the Dahutang pluton. Additionally, our study suggests that the absence of late Mesozoic Cu-Mo mineralization in the Zhejiang, Jiangxi, and Anhui Provinces (Zhe-Gan-Wan region) was probably related to low fO2 magmatism in the Cretaceous.

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Genetic Diversity and Population Genetic Structure of Cinnamomum camphora in South China Revealed by EST-SSR Markers

Forests ◽

10.3390/f10111019 ◽

2019 ◽

Vol 10 (11) ◽

pp. 1019 ◽

Cited By ~ 1

Author(s):

Zhong ◽

Yang ◽

Li ◽

Zhang ◽

Liu ◽

...

Keyword(s):

Genetic Diversity ◽

Ssr Markers ◽

South China ◽

Expressed Sequence Tag ◽

Gene Diversity ◽

Jiangxi Province ◽

Group Method ◽

Cinnamomum Camphora ◽

Wild Populations ◽

Arithmetic Means

Cinnamomum camphora is a valuable broad-leaf tree indigenous to South China and East Asia and has been widely cultivated and utilized by humans since ancient times. However, owing to its overutilization for essential oil extraction, the Transplanting Big Trees into Cities Program, and over deforestation to make furniture, its wild populations have been detrimentally affected and are declining rapidly. In the present study, the genetic diversity and population structure of 180 trees sampled from 41 populations in South China were investigated with 22 expressed sequence tag-simple sequence repeat (EST-SSR) markers. In total, 61 alleles were harbored across 180 individuals, and medium genetic diversity level was inferred from the observed heterozygosity (Ho), expected heterozygosity (He), and Nei’ gene diversity (GD), which were 0.45, 0.44, and 0.44, respectively. Among the 41 wild populations, C. camphora had an average of 44 alleles, 2.02 effective alleles, and He ranging from 0.30 (SC) to 0.61 (HK). Analysis of molecular variance (AMOVA) showed that 17% of the variation among populations and the average pairwise genetic differentiation coefficient (FST) between populations was 0.162, indicating relatively low genetic population differentiations. Structure analysis suggested two groups for the 180 individuals, which was consistent with the principal coordinate analysis (PCoA) and unweighted pair-group method with arithmetic means (UPGMA). Populations grouped to cluster I were nearly all distributed in Jiangxi Province (except population XS in Zhejiang Province), and cluster II mainly comprised populations from other regions, indicating a significant geographical distribution. Moreover, the Mantel test showed that this geographical distance was significantly correlated with genetic distance. The findings of this research will assist in future C. camphora conservation management and breeding programs.

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Petrogenesis of Silurian ultramafic–mafic plutons in southern Jiangxi: implications for the Wuyi–Yunkai orogen, South China

Geological Magazine ◽

10.1017/s0016756820001272 ◽

2020 ◽

pp. 1-16

Author(s):

Jie Yang ◽

Wei Liu ◽

Zuozhen Han ◽

Zuoxun Zeng ◽

Le Wan ◽

...

Keyword(s):

South China ◽

Lithospheric Mantle ◽

First Episode ◽

Jiangxi Province ◽

South China Block ◽

The South ◽

Mafic Rocks ◽

Formation And Evolution ◽

Early Palaeozoic ◽

T Values

Abstract The South China Block is one of the largest continental blocks located on the East Asian continent. The early Palaeozoic Wuyi–Yunkai orogen of the South China Block (known as the Caledonian orogen in Europe) is a major orogenic belt in East Asia and represents the first episode of extensive crustal reworking since Neoproterozoic time. Although this orogen is key to deciphering the formation and evolution of the South China Block, details about the orogen remain poorly defined. The Songshutang and Wushitou ultramafic–mafic units in southern Jiangxi Province, South China, have 206Pb–238U ages of c. 437 Ma, suggesting a Silurian formation age. All the Songshutang and Wushitou ultramafic–mafic rocks show relatively flat chondrite-normalized rare earth element patterns, depletions in Nb, Ta, Zr, Hf and Ti, and low ϵNd(t) values from −9.12 to −5.49 with negative zircon ϵHf(t) values from −10.84 to −2.58, resembling a typical arc magma affinity. Geochemical and isotopic data indicate that the newly identified ultramafic–mafic rocks, along with the reported Silurian mafic rocks in South China, possibly originated from the similar partial melting of an ancient subducted slab, fluid/sediment and metasomatized lithospheric mantle with varying degrees of fractional crystallization. In conjunction with other records of magmatism and metamorphism in South China, a late-orogenic extensional event led to the melting of the sub-continental lithospheric mantle in Silurian time and generated ultramafic–mafic rocks with a limited distribution along the Wuyi–Yunkai orogen and widespread late-orogenic granitic plutons in the South China Block.

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