The authors studied geochronology and geochemical data of the Songjianghe biotite monzogranite in the southern Zhangguangcai Range in order to determine its formation age,magma source,and tectonic environment. The res...The authors studied geochronology and geochemical data of the Songjianghe biotite monzogranite in the southern Zhangguangcai Range in order to determine its formation age,magma source,and tectonic environment. The results indicate that the Songjianghe biotite monzogranite was formed in the Middle Jurassic with an age of 168. 2 ± 2. 0 Ma( MSWD = 0. 93). The monzogranite was characterized by high alkali and low Ca O and Mg O,belonging to high-potassium calc-alkaline,metaluminous I-type granite. The rock is enriched in large ion lithophile elements such as Rb,Ba,and K and strongly depleted high field strength elements such as P,Ti,Nb,and Ta. It is concluded that the Songjianghe biotite monzogranite was derived from partial melting of amphibolite facies metamorphism mafic lower-crust and its formation was controlled by the Pacific Plate subduction.展开更多
基金project of National Natural Science Foundation of China(No.41272095)
文摘The authors studied geochronology and geochemical data of the Songjianghe biotite monzogranite in the southern Zhangguangcai Range in order to determine its formation age,magma source,and tectonic environment. The results indicate that the Songjianghe biotite monzogranite was formed in the Middle Jurassic with an age of 168. 2 ± 2. 0 Ma( MSWD = 0. 93). The monzogranite was characterized by high alkali and low Ca O and Mg O,belonging to high-potassium calc-alkaline,metaluminous I-type granite. The rock is enriched in large ion lithophile elements such as Rb,Ba,and K and strongly depleted high field strength elements such as P,Ti,Nb,and Ta. It is concluded that the Songjianghe biotite monzogranite was derived from partial melting of amphibolite facies metamorphism mafic lower-crust and its formation was controlled by the Pacific Plate subduction.
