【摘要】 传统地震仪观测的是一个点的位移随时间的变化,而应变仪观测的是位移的空间导数随时间的变化。在四川姑咱台用YRY-4型四分量钻孔应变仪进行的每秒100次采样观测实验,记录到三次地方震。在这样高的采样率下,YRY-4型四分量应变仪观测数据保持了令人满意的自洽和足够高的信度。观测表明,P波的应变不仅有面应变成分,而且有剪应变成分。这为澄清P波的性质,给出了直接的观测证据。根据弹性波理论,P波无旋转,可以有体应变和剪应变成分。更多还原

【Abstract】 While a traditional seismograph records the variations of displacement with time at a point,a tensor strainmeter monitors the variations of the spacial gradient of displacement.An YRY-4 borehole strainmeter at Guza,Sichuan province,recorded three local seismic events at the sampling rate of 100sps for the first time.At this high sampling rate,the data of the YRY-4 demonstrated a satisfying degree of self-consistency and sufficiently high credibility.The observation shows that P wave strain contains areal strain components as well as shear strain component.It gives direct evidence for the property of P wave.According to the theory of seismology,P wave is clarified to have no rotation,but it has volumetric strain and shear strains.更多还原