Upper mantle temperature structure of the North China Craton

We investigate three-dimensional (3-D) temperature distribution of the upper mantle at depths of 50–200 km beneath the North China Craton (NCC) and surrounding areas using high-resolution P- and S-wave velocity models as well as mineral physics and geothermal data and methods. The thickness of thermal lithosphere is also estimated assuming its bottom has a mantle adiabatic temperature of 1300 °C. Our results show that the study area exhibits an alternate distribution pattern with three weak zones and two stable blocks. The Qilian orogen, the Shanxi rift system and the Tanlu fault system are characterized by lower seismic velocity, higher temperature, higher heat flow, and thinner thermal lithosphere. The three mechanically weak zones may be related to subductions of the Indian plate and the Pacific plate beneath the Eurasian continent, resulting in thermochemical erosion of the upwelling asthenospheric material, which have played an important role in the Cenozoic partial destruction of the lithosphere beneath the NCC. The Ordos block and part of the North China Basin have higher seismic velocity, lower temperature and thicker thermal lithosphere, suggesting that the two relatively stable blocks have suffered from less damage and still kept a remanent Archean lithospheric keel.