深井电极与地表电极的自然电场对比研究  

Comparison study on natural electric field of deep-well electrode and surface electrode

作　　者：郑洪[1] 王新蕾 王春媛[1] 宋治平[1] 李永林[1] 路京林[2] 

机构地区：[1]北京市地震局,北京100080 [2]中国地震局分析预报中心,北京100036

出　　处：《地震》2000年第1期85-90,共6页Earthquake

摘　　要：通过对半无限空间和全无限空间电流密度的分布理论进行讨论，得出电流密度随电极埋 设深度的增大而减小。因此，在电法观测中，当供电电极深埋后，人工电场和自然电场可减少地 表各种噪声的干扰．提高视电阻率ρｓ和自然电位Ｖ_(ｓｐ)的灵敏度，从而更好地捕捉地震异常信息。 从北京平谷台６年多来的观测结果分析认为，深井电极相对地表电极能降低诸如人为供电、雷 击短路、冰冻期影响等各种干扰，经过宁河６．９级、６．５级和５．６级及离台站较近的三河４．８级 地震的检验，表明深井电极可明显突出地震前的异常变化量。因此，自然电场的深井电极观测是 值得推广的方法。By means of discussion of current density distribution theory in semi-infinite and the whole space, the conclusion can be reached that current density is smaller when electrode at deeper depth. If the electrode is set at deeper depth, interference of surface noise of artificial and natural electric field can be decreased. Also precision and sensibility of apparent receptivityρs and natural potential Vsp can be increased. So we can get more in- formation of earthquake anomaly. Applying the data of more than 6 years at Pinggu sta- tion in Beijing, we draw the following conclusion. Many kinds of interference I such as electricity supply,short circuit caused by lightning stroke, glacial period and so on can be decreased when deep-well electrode is used. After checking Ninghe Ms 6.9, Ms 6.5. Ms 5. 6 and Sanhe Ms 4.8 earthquakes, we can also get that anomaly variation can be prominent when the deep-well electrode is used. Therefore, deep-well electrode observation of natu- ral electric field is a good technique, which is worth spreading.

关 键 词：深井电极 地表电极 自然电场 地震前兆 

分 类 号：P315.7[天文地球—地震学]