濃尾平野における自噴帯の変遷

抄録

The area of flowing well is widely recognized in the Nobi Plain, and flowing groundwater has been developed with the improvement of technology for drilling. As modern industry has become prosperous, a large quantity of groundwater has been utilized mainly for textile and chemical industries.

In the early 1930s, the artesian flowing of shallow wells has stopped its characteristic phenomena, and those areas have been enlarged. During the high economic growth period in 1960s, the artesian flowing of deep wells with a high pressure head also stopped in some areas of the Plain. As the result of reduction in the discharge spring in the alluvial fan called “Gama”, the number of local fresh water fish “Hariyo” living in the spring has also decreased.

It is pointed out from the present study that the artesian flowing well is recognized in the following four areas of the Nobi Plain : (1) North-eastern Ogaki City and eastern Ogaki City, (2) the terminal part of the Ibi River and the Kasu River alluvial fan in the northern Ogaki City, (3) the terminal part of the Ai River alluvial fan in the western Ogaki City and the south-eastern Tarui Town, and (4) the bank of the Makida River in the southern Ogaki City and Yoro Town. Because of the decrease in withdrawal of groundwater by the recent regulation of groundwater use, the area of artesian flowing shows little change as compared with previous conditions.