【摘要】 <正> 一、引言长清地震台于1998年9月14日在台站数字化改造过程中安装体积式应变仪一台,灵敏度达到1×10^-9,产出的数据连续稳定,固体潮汐完整清晰。1999年9月至2001年1月出现数次大的突跳,并且与部分远震相对应。尽管对其形成机理无法解释,但是通过对仪器系统以及气压、水位、降雨等干扰因素的分析对比后,证实前兆数据突更多还原

【Abstract】 A set of volumetric strain-meter, Type-TJ213, was mounted at Changqing Observatory in 1998. Its sensibility reaches 1×10^-9. Since then, it has worked continuously and rather stable. Earth tide can be recorded clearly and completely. In the period of 1999.09 to 2001.01, there have experienced several times of largeamplitude pulse in the observatory data, which were corresponding to some far-field earthquakes. After interference factor analyses of air-pressure, ground-water level, and rainfall etc., we believe that they belong to strong stress disturbances caused by far-field earthquake generation processes. However, the mechanism of such stress disturbances needs to be further studied.更多还原