摘要
A belt of low Al-Trondhjemite-Tonalite-Diorite (TTD) series has been recognized along the Northern Qinling Orogenic Belt (NQOB), which is dated as 430―399 Ma and charac-teristic of positive εNd(t ) values. Geochemical features and trace elements simulation indicate that the TTD series was probably originated from differently partial melting of tholeiitic rocks from the Erlangping group. Thermodynamic analysis on the residue phases of the partial melting pro- cesses suggests that the TTD series may represent a dynamic process of temperature-increasing and pressure-decreasing, indicating an extension and thinning process of a thickened crust.
A belt of low Al-Trondhjemite-Tonalite-Diorite (TTD) series has been recognized along the Northern Qinling Orogenic Belt (NQOB), which is dated as 430―399 Ma and charac-teristic of positive εNd(t ) values. Geochemical features and trace elements simulation indicate that the TTD series was probably originated from differently partial melting of tholeiitic rocks from the Erlangping group. Thermodynamic analysis on the residue phases of the partial melting pro- cesses suggests that the TTD series may represent a dynamic process of temperature-increasing and pressure-decreasing, indicating an extension and thinning process of a thickened crust.
基金
supported by the National Natural Science Foundation of China(Grant No.40372032)
the Research Fund for the Doctoral Program of Higher Education of the Ministry of Education,and Analyzing Foundation of Peking University
