临汾台摆式倾斜仪平行观测的差异性特征及其观测布局建议

DIFFERENTIAL CHARACTERISTICS OF PARALLEL OBSERVATION DATA RECORDED BY PENDULUM TYPE TILTMETER AT LINFEN SEISMOSTATION

根据临汾地震台石英摆、垂直摆、宽带垂直摆3套摆式倾斜仪器的观测资料,对山西中南部几次中等地震进行分析,发现在地震前各仪器同测向曲线有一定的异常反映,但异常并非呈相关一致性变化,有的还表现出明显的差异性特征;在同一台址条件下,异常的差异性与仪器的工作周期、动态响应范围、记录频段等有关;河津地震前后宽带垂直摆倾斜仪记录到的连续阶跃扰动(错位掉格)可能是慢地震现象,由此说明了宽频段仪器的优越性及发展性;建议在形变台网观测中,同一台站应建立宽频或多种同类型的形变观测仪器,组成尽量具有低、中、高频段的全面观测系统,这可能对于扑捉近震的短临前兆异常有实效意义。

Through the analysis of morphological patterns recorded with three kinds of tihmeters quartz pendulum, perpendicular pendulum and broadband perpendicular pendulum before several moderate earthquakes in the south of Shanxi, some anomalous reflects in the same observation direction for each instrument are identified before earthquakes. However, these anomalies did not show coincident variation, but show obvious differential features. Under the same station condition, anomaly difference is related to work periods, dynamical response range and recording frequency range of instrument. The slow earthquake phenomenon recorded by broadband perpendicular pendulum tiltmeter before and after Hejin earthquake illustrates the observation advantage of broadband deformation instruments.