Petrogenesis of the Granites in the Yandangshan Area, Southeastern China: Constraints from SHRIMP U-Pb Zircon Age and Trace Elements, and Sr-Nd-Hf Isotopic Data  

作　　者：Yaqin Luo Haiyan Qin Tao Wu Zilong Li 

机构地区：[1]School of Earth Sciences,Zhejiang University,Hangzhou 310027,China [2]The 11th Geological Section of Zhejiang Province,Wenzhou 325006,China [3]Ocean College,Zhejiang University,Zhoushan 316021,China

出　　处：《Journal of Earth Science》2020年第4期693-708,共16页地球科学学刊（英文版）

基　　金：funded by the National Natural Science Foundation of China (Nos. 41702047,41541018,41072048);Department of Science and Technology (No. 2014C33023);Geological Exploration Bureau (No. 201531);Department of Land and Resources (No. 2015005)。

摘　　要：New geochemical and geochronological data of two types of granites,which are located in Yandangshan area,southeastern Zhejiang Province,were presented to constrain their magma condition,origin and the genetic relationship between them.The SHRIMP zircon U-Pb dating of Dongshan and Hesheng granite in Yandangshan area shows that they were formed at 114±1 and 103±2 Ma,respectively.Samples from the Dongshan granite have high Si O2(76.4 wt.%–76.9 wt.%)and total alkaline(K2O+Na2O=8.35 wt.%–8.47 wt.%)contents,but low Fe OT(0.89 wt.%–1.15 wt.%),Mg O(0.21 wt.%–0.22wt.%),and Ca O(0.24 wt.%–0.34 wt.%)contents and high A/CNK(~1.1)values,belonging to the peraluminous and magnesian granite.The Hesheng granite has high Si O2(72.2 wt.%–77.5 wt.%),total alkaline(K2O+Na2O=8.05 wt.%–9.41 wt.%)and Fe OT contents(1.20–2.06),and high A/CNK values(1.0–1.1),but low in Mg O(0.12 wt.%–0.29 wt.%)and Ca O(0.24 wt.%–0.34 wt.%)contents.Samples from the Hesheng granite also have high Fe OT/Mg O(6.9–10.0)and 10 000×Ga/Al(2.6–3.4)ratios similar to the ferroan/A-type granite.All the samples are enriched in LREE but have produced negative Eu anomalies(Eu/Eu*Dongshan=0.45–0.47;Eu/Eu*Hesheng=0.17–0.55),Ba,Nb,and Ta,while the REE contents of the ferroan/A-type granite(Hesheng)are higher than that of the magnesian granite(Dongshan).The(87Sr/86Sr)i value of the magnesian granite is slightly higher than that of the ferroan/A-type granite and itsεNd(t)value(-6.8)is lower than the latter(-6.0–-5.9).In addition,theεHf(t)value(-11.8–-4.2)of magnesian granite is also lower than that of the ferroan/A-type granite(-8.3–-2.0),indicating that there may be more mantle-derived components in the source area of the ferroan/A-type granite.Zircon saturation thermometer(TZr)and Ti-in-zircon thermometer(TZircon)are used to estimate the temperature of the magma source,and the results show that the magma temperature of the magnesian granite(average TZr=798oC;average TZircon=792oC)is lower than that of the ferroan/A-type granite(aver

关 键 词：magnesian and ferroan/A-type granite PETROGENESIS Yandangshan South China 

分 类 号：P588.121[天文地球—岩石学] P597[天文地球—地质学]