Dehydration Temperature of Serpentine at Elevated Temperatures and Pressures by Electrical Conductivity Method and Its Implications

Dehydration temperatures of serpentine were measured in the pressure range between 1.0GPa and 5.0GPa by using the electrical conductivity metod simultaneously at high temperatures and high pressures.The results show that with increasing pressure th dehydration temperature of antigorite increases slightly below 2.0GPa ,but drops markedly above2.0GPa .This strongly suggests that high pressure would favor the dehydration of serpentine minerals and the water released thereby would be an important source of fluids involved in magmatism in a subduction zone and mantle metasomatism,Meanwhile,the greatly enhanced electric conductivity in the presence of water may be one of the reasons underlying the occurrence of a high-conductivity zone in the lower crust.

Dehydration temperature of serpentine at elevated temperatures and pressures by electrical conductivity method and its implications

Dehydration temperatures of serpentine were measured in the pressure range between 1.0 GPa and 5.0 GPa by using the electrical conductivity method simultaneously at high temperatures and high pressures. The results show that with increasing pressure the dehydration temperature of antigorite increases slightly below 2.0 GPa, but drops markedly above 2.0 GPa. This strongly suggests that high pressure would favor the dehydration of serpentine minerals and the water released thereby would be an important source of fluids involved in magmatism in a subduction zone and mantle metasomatism. Meanwhile, the greatly enhanced electric conductivity in the presence of water may be one of the reasons underlying the occurrence of a high-conductivity zone in the lower crust. This project was financially supported by the National Natural Science Foundation of China.