Abstract:

The Jingdezhen ductile shear zone is located at the core of the Neoproterozoic Jiangnan Orogen. Structural features and
geochronology of the Jingdezhen ductile shear zone have a key implication for the Neoproterozoic to Early Paleozoic tectonic evolution of the South China Block. The Jingdezhen ductile shear zone is ~180 km long in the NE-striking orientation and ~7 km in maximum width. Two-phase ductile strike-slip shearing was identified based on detailed field investigation and observation of oriented thin sections. Moreover, the kinematic indicators and temperature-pressure conditions were studied in this paper. The early sinistral ductile strike-slip with thrusting occurred at 400~500℃ and differential stress of 40~300 MPa, whereas the dextral ductile shearing at 300~400℃ and differential stress of 120~300 MPa. Combined with the previous work, the sinistral strike-slip with thrusting of the Jingdezhen ductile shear zone took place at late stage of the Neoproterozoic orogen in the South China Block (810~800 Ma), as a result of transformation from syn-orogeny compression to post-orogeny extension. The dextral shearing of the Jingdezhen ductile shear zone occurred in the Early Paleozoic, triggered by the Early Paleozoic intracontinental orogeny of southeast China

Key words: kinematic indicator, temperature-pressure condition, Jingdezhen ductile shear zone；Neoproterozoic Jiangnan Orogen;South China Block