Late Paleozoic Tectonic Analysis and Geochronology Study by Shrimp Zircon U-Pb Dating

Аннотация

Sinkiang Hami Redstone Copper in China is a super-large volcanic hydrothermal deposit formed as a result of multi-stage secondary tectonic activity in the Hercynian period of tectonic movement. In this work, we have studied the effect of the geomechanical nature on the structure of faults stretched in different directions and have studied the age of Hercynian U-Pb detrital rock in trenches by SHRIMP zircon dating. Our studies have shown that there were strong tectonic plate movements 286-218 million years ago, and a main mineralization stage in the period 285-270 million years ago. Our results showed four developmental fault zones with different properties in the Redstone copper: the first stage is represented by nearly EW and NWW, extensional fault zones in the Upper Carboniferous period, with which formation of the ore structure is associated; the second stage is represented by a nearly SN fault zone formed at the boundary between the Upper Carboniferous and the Lower Permian periods, in which mineralization occurred; the third stage is represented by a NE and NEE fault zone in the Upper Permian period; and the fourth stage is represented by NE faults in the Lower Triassic period, which are mainly broken ore structures. Study of the tectonic stresses showed the presence of the following stresses: NNE tension, nearly EW tension, a pair of sinistral SN horizontal shears and a pair of NNE horizontal shears, a pair of dextral SN horizontal shears and EW tension.