• 责任者：Chen Lei (Key Laboratory of Metallogeny and Mineral Assessment ; MLR ; Institute of Mineral Resources ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Zhao Yuanyi
• 刊名：Geology and Prospecting
• 出版年：2013
• 卷期：49(6)
• 关键词：流纹英安岩 ; rhyodacites ; 花岗斑岩 ; granite porphyry ; 江西 ; Jiangxi Province
• 页码：p.999-1016
• 图表：14 illus., 2 tables, 73 refs.
• 分类号：0801
• issnNo：ISSN0495-5331
• isbnNo：CN11-2043/P

     The Shannan ore district is located in the north of the Xiangshan ore field, where rhyodacite and granite porphyry which are the most important host rocks exposed in the surface. Geochemistry and Sr-Nd isotope of the rocks show the rhyodacite and granite porphyry is characterized with high Si （the qualities ofSiO2 are 69.47% -72.19% and 72.32% ~78.6%, especially）, rich Na （the ratios ofK20/Na20 are0.4-0.52 and0.4-0. 67, especially） and with alkaline rock characteristics. The rhyodacite and granite porphyry with peraluminous characteristics are belong to high k calc al- kaline and shoshonite series. Rhyodacite and granodioritic porphyry are enrich in Th, U, Pb et al. high field-strength elements （HFSEs） and Rb,K et al. large-ion ithophile elements （LILEs）, and depleted Zr,Ti,Ta,Ce et al. HFSEs and Ba,Sr et al. LILEs. The show the similar chondrite-normalized REE patterns, with negative Eu anomalies （δEu were 0.41 - 0.56 and 0.09 - 0.32, especially）, enrich in LREEs and depleted HREEs （the ratio of LREE/HREE were 9.32 - l 1,59 and 2, 12 - 8.27, especially） and （La/Yb） ~ were 10.59 - 14.26 and 1.41 - 9.47, especially. The crystallization temperature of rhyodacite and granite porphyry based on zircon saturated thermometer are 812.5 - 904.9℃ and 772. l - 826℃ , especially. The chemistry characteristics of rhyodacitc and granite porphyry show they formed in a low pressure environment. The Sr-Nd isotope show the rocks with majoe Isr and lesser εNd （t） （ -7.81 -  -8.93）. Chemistry and Sr-Nd isotope characteristics show rhyodacite and granite porphyry are S type, and experience partial melting and assimilation constrain during their forming process. The source region of the rocks and uranium mineralization are provided with intense shell source characteristics, and the source rocks are may be arenaceous rock and argillaceous rock of the Proterozoic metamorphic rocks in the area. Combined with the chronology resulted by other scholar and chemistry, Sr-Nd isotope of this research, we think rhyodacite, granite porphyry and uranium mineralization in Shannan ore district of Xiangshan ore field are formed during the lithosphere extension and thinning of the South China Craton, which was caused by the subduction of Pacific plate in Mesozoic.