桂林理工大学学报2018，Vol.38Issue(4)：597-613,17.DOI:10.3969/j.issn.1674-9057.2018.04.001
桂北猫儿山印支期花岗岩成因:来自岩石学、岩石地球化学、锆石U-Pb年龄和Hf同位素的证据
Genesis of Indosinian granites in Maoershan, northern Guangxi: evidence from petrology, geochemistry, zircon U - Pb ages and Hf isotope
摘要
Abstract
The tungsten polymetalic and granite type uranium deposit from Maoershan area are mainly related to the Indosinian granites. This thesis carried out a detailed petrology,gepchemistry characteristics and zircon U - Pb dating on the Indosinian granites. Early granite formed in 232 - 228 Ma and the late in 224 - 208 Ma. Tow stages granites show the feature of high of SiO2(70. 82％ - 76. 12％) and Al2O3(12. 87％ - 14. 78％) . The early stage granite belongs to strongly peraluminous,A /CNK range from 1. 40 - 1. 67. However, the late stage granite belongs to weakly peraluminous-strongly peraluminous,A /CNK range from 1. 01to1. 28. Tow stages granites are both characterized by enrichment of Rb,Th,U,Zr and Hf,severe depletion of Ba,Sr,P,Ti and Eu. The ΣREE has a range of 33. 95 × 10 - 6 - 323. 88 × 10 - 6,slight enrichment of LREE(LREE /HREE = 2. 60 - 11. 76) , strong depletion of Eu(δEu = 0. 11 - 0. 40) ,and weak tetrad of rare earth elements pattern(TE1,3 = 1. 00 - 1. 16) . The late granite has a relatively high value of εHf(t) (- 4. 88 to - 8. 91) and contains a small amount of mafic microgranular enclaves,indicating the occurrence of magma mixed in the formation of late granite. It is considered that the Indosinian granites from Maoershan were related to the lithospheric extension after the Indosinian Orogenesis,and formed from partial melting of the Mesoproter-ozoic crust material,and a small amount of mantle material was added to the late granites.关键词
花岗岩/镁铁质微粒包体/地球化学/锆石U-Pb年龄/Hf同位素/印支期/猫儿山Key words
granite/mafic microgranular enclave/geochemistry/zircon U - Pb ages/Hf isotope/Indosinian/Maoershan!引用本文复制引用
覃洪锋,黄锡强,蒋剑,谭斌,潘金光,谢植贵..桂北猫儿山印支期花岗岩成因:来自岩石学、岩石地球化学、锆石U-Pb年龄和Hf同位素的证据[J].桂林理工大学学报,2018,38(4):597-613,17.基金项目
中国地质调查局项目(12120114084101) （12120114084101）
