%0 Journal Article
%T Geochemistry and petrogenesis of Jurassic high Sr/low Y granitoids in eastern China: Constrains on crustal thickness
%A Xiaoyue Ge
%A Xianhua Li
%A Zhigang Chen
%A Wuping Li
%J Chinese Science Bulletin
%@ 1861-9541
%D 2002
%I 
%R 10.1360/02tb9216
%X The Jurassic high Sr/low Y granitoids in eastern China are characterized by high Sr/Y (27每166) and La/Yb (14每66) ratios, low abundance in Y (6每21 米g/g) and Yb (0.5-2.0 米g/g), comparable with those of adakites defined by Defant et al. Thus, they were recently considered as adakitic rocks by some researchers. Compared with the typical adakites in circum-Pacific margins, however, these high Sr/low Y granitoids have higher K2O ( 3.5%) but lower Al2O3 ( 16.0%) as well as lower Mg# ( 38) and 汛Srn ( 1.23) values. Furthermore, they show relatively flat HREE patterns with Y/Yb values of  10 close to the chondritic value. These geochemical characteristics indicate a residue mineral assemblage of hornblende, garnet and plagioclase for these high Sr/low Y granitoids melt. Thus, they were generated by partial melting at 9每13 kbar (30每45 km in depth), similar to the Archaean high-Al TTG rather than the modern adakites. Generation of these high Sr/low Y granitoids cannot be considered as evidence for a thickened crust (>50 km) and/or the presence of the ※Eastern China Plateau§ in Jurassic.
%K granitoids
%K adakite
%K TTG
%K Jurassic
%K eastern China
%U http://link.springer.com/article/10.1360/02tb9216