武威地电台映震能力讨论
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摘要
本文研究了武威地电台周围１５０ｋｍ范围内发生的景泰６．２、门源６．４、天祝西４．７、旦马５．６、雅布赖４．７级地震和共和７．０级地震（Δ＝２７０ｋｍ）该台地电阻率（ρ＿ｓ）变化，结果显示：对于前４次地震，该台ＥＷ进测值出现１０￣（－１）─１０￣（－２）量级的ρ＿ｓ短临异常，共和和雅布赖地震前后观测到１Ｏ￣（－１’量级的ρ＿ｓ短期下降异常。作者研究认为，ρ＿ｓ异常可能是该台ＥＷ这探测范围内介质不完整，孕震后期震源力学过程引起地下水沿测区内次级断层、裂隙或裂缝活动造成的。最后本文指出，该台ＥＷ道测值对其周围特定位置发生的中强以上地震，在短临阶段映震能力较强。
Earth-resistivity(ρ_s)changes of Wuwei geoelectric station before and after earthquakes ofM 6.2 in Jingtai county,M 6. 4 in Menyuan,M 4. 7 in West of Tianzhu,M 5. 6 in Danmaand M 4. 7 in Yabulai(Δ≤150 km),as well as M 7. 0 in Gonghe(Δ=270 km) in this paper.Conclusions are follows:( 1)Short-impending ρ_s anomalies up to 10￣(-1)─10￣(-2) magnitude wererecorded in EW observation direction at the station before the former 4 earthquakes, short-term ρ_s anomalies up to 10￣(-2) magnitude which were decreased were recorded before the Gongheand Yabula earthquakes.(2)The short-impending ρ_s anomalies in the direction were probablycaused by the move of ground water along second faults,rifts or fissures in the late period ofseismogenic process, since earth medium within the range of exploration in the direction wasfragmentary. Finaly, author thinks,the reflecting earthquake ability of short-impending ρ_schange in EW direction of the station is higher for moderate and strong earthquakes occurredin certain region around the station.
Earth-resistivity(ρ_s)changes of Wuwei geoelectric station before and after earthquakes ofM 6.2 in Jingtai county,M 6. 4 in Menyuan,M 4. 7 in West of Tianzhu,M 5. 6 in Danmaand M 4. 7 in Yabulai(Δ≤150 km),as well as M 7. 0 in Gonghe(Δ=270 km) in this paper.Conclusions are follows:( 1)Short-impending ρ_s anomalies up to 10￣(-1)─10￣(-2) magnitude wererecorded in EW observation direction at the station before the former 4 earthquakes, short-term ρ_s anomalies up to 10￣(-2) magnitude which were decreased were recorded before the Gongheand Yabula earthquakes.(2)The short-impending ρ_s anomalies in the direction were probablycaused by the move of ground water along second faults,rifts or fissures in the late period ofseismogenic process, since earth medium within the range of exploration in the direction wasfragmentary. Finaly, author thinks,the reflecting earthquake ability of short-impending ρ_schange in EW direction of the station is higher for moderate and strong earthquakes occurredin certain region around the station.
引文
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