The author collectd pretty many data concerning the deep wells in Japan. The term “deep well” is not used here as in hydraulics but as customary use in Japan, where means artesian well. Most of them are 6 to 12 inches in diameter and 60 to 120 meters deep. The records give us the owner or the name of a well, its location, the diameter (t) and the yield (Q).
The author discussed these records under the following three assumptions : 1) All wells tapped all available confined aquifers, 2) Sinking of the water table in a well by pumping is restricted to 30 meters in general at the maximum state, 3) All records regarding the yields of wells are assumed to be exact, The relation between Q and r is shown in a logarithmic curve (Figs. 1-6). Utilizing these relations converting factor is calculated for each principal confined water district, as shown in tables 1-4, with which the discharge of a well of arbitrary diameter can be converted to that of 12 inches in diameter. Then it proceeded to discuss the hydrological characters of each confined water district, comparing the gradients of Q-r curve with the semi-logarithmic curve (Fig. 7). Two groups can be distinguished : one with the curve of steeper gradients is found in the Kwanto, Ariake Sea and Osaka Bay districts, while the other with a curve of gentler gradients is met with in the Ise Sea, Hokuriku and Setouchi regions.
抄録全体を表示