2.0 GPa、室温至1 200 ℃条件下斜长角闪岩的纵波速度及其衰减

 利用YJ-3000 t 压力机，在2.0 GPa、室温至1 200 ℃条件下，测量了新疆库地地区斜长角闪岩的纵波速度（v_p）和力学品质因子（Q值）。实验结果表明：斜长角闪岩的v_p和Q值随温度的升高而降低，在升温的初始阶段，v_p和Q值随温度下降的幅度较小，随着温度的升高其下降的幅度逐渐增大；由于斜长角闪岩的各向异性，导致了在3个方向上v_p随温度而下降的幅度显著增大时的温度不同，其中x和y方向为812 ℃，z方向为673 ℃。而在各方向上的Q值随温度下降的幅度显著增大时的温度相差不大，约为812 ℃。观察回收的实验产物表明：当温度大于647 ℃时，产物中开始出现熔体，v_p在x和y方向上的下降幅度没有明显的变化，而在z方向上的下降幅度增大；此时熔体对Q值的影响不大。当温度大于812 ℃时，产物中的熔体含量明显增多，v_p和Q值下降的幅度都显著增大。据此认为，部分熔融是弹性波速度减小和衰减增大的主要原因。

COMPRESSIONAL VELOCITY AND ATTENUATION IN AMPHIBOLITE AT 2.0GPa AND UP TO 1200℃

Compressional wave velocity and attenuation in amphibolite collected from Kudi, Xinjiang Province were measured at high pressure (2.0 GPa) and high temperature (up to 1 200 ℃). The experimental results show that v_p and Q values decrease with the increase of temperature. At the beginning of increasing temperature, v_p decreases slowly, and then decreases rapidly with the higher temperature. Because of amphiboliteps anisotropy, the temperature at which v_p decreases quickly in different directions is different. The temperature is 812 ℃ in x and y and 673 ℃ in z. However, the temperature at which Q decreases quickly is about 812 ℃ at the three directions. It can be concluded from the experimental results of minerals that as the temperature is higher than 647 ℃, the melt appears. The scope of v_p decreasing with temperature in x and y directions is not various than before. It increases in z direction. However, the melt does not affect Q values. As the temperature is higher than 812 ℃, the melt is more than before, v_p and Q values decrease more quickly. Therefore, partial melting is the main reason for elastic wave velocity decreasing and attenuation increasing.