Abstract:
The study area is located in the junction zone between the Yangtze platform and the SongpanGanzê geosyncline, belonging to the central sector of the Longmen MountainJinping Mountain orogenic belt. This area has undergone four stages of tectonic evolution, i.e.: the formation of the basement, development of the pasive continental margins, folding and mountainmaking and intracontinental mountainmaking. Especially the last two stages gave rise to the present tectonic features. From the viewpoint of the tectonic slabs, the tectonic slabs have been distinguished with the ductile shear zones as the boundaries; thus a tectonic framework of “four zones and five slabs” has been established.