Wakita H
Science. 1975 Aug 15;189(4202):553-5. doi: 10.1126/science.189.4202.553.
Coseismic water level changes associated with the Izu-Hanto-oki earthquake of 9 May 1974 were recorded in 59 among 95 observation wells located in the districts of Tokai and Kanto, Japan. The spatial distribution of wells in which the groundwater level rose or fell is rather systematic. The areas in which these wells are located closely coincide with the areas of contraction and dilatation expected by the faulting. This strongly suggests a possible correlation between the observed changes in groundwater level and the tectonic strain. The results may indicate that the water level of wells is able to monitor at least acute coseismic strain changes.
1974年5月9日伊豆半岛冲地震所引发的同震水位变化，在日本东海和关东地区95口观测井中的59口被记录下来。地下水位上升或下降的井的空间分布颇具系统性。这些井所处的区域与断层作用预期的收缩和扩张区域紧密重合。这有力地表明，观测到的地下水位变化与构造应变之间可能存在关联。结果可能表明，井水位至少能够监测同震时的急性应变变化。
