板室温泉における温泉水の流動状況に関する考察

概要

論文の詳細を見る
Itamuro spa is located on southwest foot of Nasu volcano, Central Japan. And the surroundings consist mainly of tuff, tuff breccia and rhyolite belonging to Fukuwata formation of tertiary age. There are 20 spring wells in the spa, drilled 85-890 m deep, and 15 wells marks temperature ranging 22.4-50.1℃, 10 wells issue thermal water naturally 58.3-711.9 l/min and from 5 wells 68.8-400 l/min of the water is pumped up. Among 14 wells, those issuing water is examined chemically, 12 wells issue thermal water of Na・Ca-SO_4 type, one well of Na・Ca-Cl-SO_4 type and one well of groundwater type. From hydrogeological investigation, the followings are clarified: (1) Dominative discharge area of the water situates about 350 m downstream from junction of Nakagawa river and Yukawa river. (2) Vertical and horizontal distribution of the main chemical components of thermal water can be explained by thermal water flow system. (3) Two chemical types of the water above mentioned are bounded by a fault, running N-S direction and inferred impermeable layer. (4) Geologically and chemically, close correlation between Itamuro and Nasu spas is denied.
地学団体研究会の論文
1983-05-25