P-wave velocities in the rocks of Dabieshan, central China were measured at pressures up to 5.0 GPa and temperatures up to 1 300℃. The ultrahigh pressure eclogites have the highest density and P-wave velocity (Vp) an...P-wave velocities in the rocks of Dabieshan, central China were measured at pressures up to 5.0 GPa and temperatures up to 1 300℃. The ultrahigh pressure eclogites have the highest density and P-wave velocity (Vp) and lower anisotropy. Pressure derivatives of the eclogites range from 0. 22 to 0. 33 km. s-1 GPa-1. Average temperature derivative of the eclogites is - 3. 41×10-4 km. s-1. °C -1. The density and VP of the eclogites imply that there will be two united possibilities related to crust-mantle recycling after the eclogite formed in the deep lithosphere. One is that some eclogites in the deep lithosphere were detached and sunk into deeper mantle due to their denser density. Another is that some eclogites returned to the crust and exposed to the surface.Small amounts (<12%) of eclogites may be still exist in the deep crust beneath Dabieshan based on our calculation.展开更多
文摘P-wave velocities in the rocks of Dabieshan, central China were measured at pressures up to 5.0 GPa and temperatures up to 1 300℃. The ultrahigh pressure eclogites have the highest density and P-wave velocity (Vp) and lower anisotropy. Pressure derivatives of the eclogites range from 0. 22 to 0. 33 km. s-1 GPa-1. Average temperature derivative of the eclogites is - 3. 41×10-4 km. s-1. °C -1. The density and VP of the eclogites imply that there will be two united possibilities related to crust-mantle recycling after the eclogite formed in the deep lithosphere. One is that some eclogites in the deep lithosphere were detached and sunk into deeper mantle due to their denser density. Another is that some eclogites returned to the crust and exposed to the surface.Small amounts (<12%) of eclogites may be still exist in the deep crust beneath Dabieshan based on our calculation.
