Hydrogeological Investigations of Shinjo Basin. Yamagata Prefecture
1978 Volume 20 Issue 1 Pages 126-142
Details
1978 Volume 20 Issue 1 Pages 126-142
The hydrogeological survey was carried out in Shinjo Basin in 1975 and the following results are obtained.
1) The upper Neogene formations and Quarternary strata are developed in Shinjo Basin.
2) The deluvium and alluvium are covered with the fan deposits which are 30 to 90 meters in thickness.
3) The groundwater aquifers in this basin are divided into the I, II, III and IV horizon beds according to the electric ground resistivity method.
4) The hydraulic conductivity is in the order of 10-3cm/sec as in Yonezawa Basin but at the surface layer (to 30 meters in depth) it is 10-1∼10-2cm/sec.
5) The specific capacity of Shinjo Basin is relatively small compared with that of Yamagata or Yonezawa Basin.
6) The ground water is reserved in the uppermost Miocene (Sakegawa Formation). It must be noticed that the unreasonable pumping up from the uppermost Miocene Formation will cause the land subsidence.
