南北地震带上的钻孔应力—应变观测

Borehole Stress-Strain Observatory on South-North Seismic Zone

回顾了我国运用钻孔应力—应变手段在南北地震带上进行地震观测、预报的实践。第一代钻孔应力观测仪器,在南北地震带的北段和南段,都记录到了很有价值的与构造运动以及地震有关的应力变化,但是观测工作中还存在诸多问题;第二代钻孔应变观测仪器,精度大大提高,除记录到一些地震趋势前兆变化外,还记录到可靠的短临变化,在地震预报中显示了一定的有效性。在南北带未来的观测和震情跟踪工作中,除改进标定方法以进行定量研究外,更应该注意观测效果对比,用实验场或母子台的方式建立小间距台网,以取得可对比的资料。

The borehole stress-strain observation on the SN seismic zone started in 1971. The first-generation instruments, borehole stress-meters, recorded valuable stress changes related to the tectonic and seismic processes in the northern and southern parts of the seismic zone despite of various problems. The second-generation instruments, borehole strain-meters, with much higher accuracy, recorded some trend anomaly changes and believable imminent precursory changes prior to earthquakes, thereby proving their function in earthquake prediction. In future observation and trace of seismicity on the SN seismic zone, it is suggested that, apart from improving calibration method for quantity research, more attention should be paid to the comparison of adjacent stations＇ measurement results; and in order to obtain comparable data, the distance between every tow stations should be as short as possible in the construction of network, just like that in test site network or parent-child clusters.