摘要:Compressional wave velocities ( V p) in quartz aggregate were measured to quantify the effect of pore fluid (H2O) on V p at high pressure-temperature ( P - T ).Ultrasonic measurements were conducted on dry and wet quartz aggregate from room temperature to 500°C at 0.5 GPa using a piston cylinder apparatus.The experiment showed a 4% decrease in measured V p in quartz aggregate with increasing H2O content to 1 wt.%, whereas the temperature derivative of V p ( ∂V p/ ∂T = -2.8 to -4.9 × 10-4 km s-1°C-1) in wet quartz aggregate remained almost the same as for the dry quartz aggregate ( ∂V p/ ∂T = -5.2 × 10-4 km s-1°C-1).Our high-pressure, high-temperature experiments show that a small amount of pore fluid (0.4 to 1.0 wt.% H2O) can significantly reduce V p under the P - T conditions of the middle crust.