Huge anomaly variation appearing in leveling of Linfen Seismological Station from Jul.2009 to Jan.2010 is investigated and analyzed.The reasons that cause the variation are：（1） A tomb deep 5 meters was dug near BM3 site in the winter of 2008 and irrigation of farmland many times.（2） The soil 11 to 19.1 meters below BM3 site is of low-resistivity,where underground water is rather abundant.Long-term underground water activity leads to saturated yielding of loess and site goes down under the action of gravity.（3） There is an active normal fault of Holocene below BM3 site,whose upper breakpoint is near to ground surface.Also,there is a drain channel of underground water 35 meters below.Fault activity changes stable water reservoir system and thus upper soil layer structure is destroyed.Internal scour action of underground water carries off partial soil body,so that ground subsides.%对2009年7月至2010年1月临汾台水准出现的巨幅异常变化进行调查和分析,认为引起变化原因是：（1）由BM3点附近5 m的地方2008年冬天新挖的一个坟墓加之多次农田灌溉引起的;（2）BM3点下方11 m～19.1 m处是低阻体,地下水较丰富,长期地下水运动导致黄土湿陷,在重力作用下引起点位下沉;（3）在BM3点下方有一正断层,上断点接近地表,为全新世活动断裂,35 m以下为一个地下水的疏水通道,断层的活动改变了原来稳定的储水构造,使上部土层结构遭到破坏,地下水的潜蚀作用增强带走了部分土体,而引起地面沉降。
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