总强度在地震磁效应观测中的有效性

ON THE EFFECTIVENESS OF THE MEASUREMENT OF GEOMAGNETIC TOTAL FIELD IN MONITORING THE SEISMO-MAGNETIC PHENOMENA

  • 摘要: 质子旋进磁强计(PPM)作为地磁场总强度标量测量的仪器, 具有稳定、操作简便、测量迅速等优点.其性能很适于地震磁现象的观测.可是, 总强度在震磁现象观测中是否有效, 中外从事此项研究工作的学者看法不一.本文以区分局部地磁异常的源场公式为基础, 论证了在地表地震磁异常的全域内, 总强度的变化不能为零, 其变化幅度ΔF与垂直分量的变化幅度ΔZ应大体相当, 这与实际震例和地震磁效应模型计算结果相吻合.这就使我们有可能充分利用PPM 作为总强度标量测量仪器的优越性, 在重点地区布署以总强度测量为主的台站和流动测网, 以尽力捕捉地震磁现象时空变化的全过程.

     

    Abstract: Such features as higher stability, quick operation, and convenient maintenance of the proton precession magnetometer in the use of geomagnetic total field measurement make it very suitable to be installed in dense network of geomagnetic observatories or survey sites for monitoring the seismo-magnetic phenomena. But some people propose that it is necessary to measure the geomagnetic component, especially the vertical, to monitor the seismo-magnetic phenomena.In this paper the effectiveness of the total field measurement in monitoring the seismo-magnetic phenomena is proved on the basis of the formula separating local anomaly origin into external and internal parts. It is shown that the range of anomaly of the total field, △F, can not be zero anywhere in the entire anomalous region and that it is comparable with the range of the component anomalies, △H or △Z. This makes it possible to monitor in seismic region the whole process of the seismo-magnetic phenomena, specially and temporally with a set of dense observatories or survey sites using PPM.

     

/

返回文章
返回