@article{oai:niigata-u.repo.nii.ac.jp:00028197,
 author = {青木, 滋 and 藤田, 至則 and 茅原, 一也 and 佐藤, 修 and 横堀, 正純 and 土屋, 泉 and 宇都宮, 真 and 鈴木, 幸治},
 journal = {新潟大学積雪地域災害研究センター研究年報, 新潟大学積雪地域災害研究センター研究年報},
 month = {Nov},
 note = {The Ura river, a tributary of the Hime river running through Nagano and Niigata Prefectures, covers the basin area of 22 km^2 with length of 12 km. The basin area is well-known by the frequent occurrence of slope failures and debris flows. In 1912 the Hime river was attacked by the huge amount of debris flow related large-scaled sliding of slope at mt. Hieda (Fig.1). Recently debris flows sometimes ran down the Ura river every year. The present paper deals with the geological and geochemical features in the said river basin for the purpose of analysis as to mechanism of occurrence of slope failures and debris flows. The results or our studies can be summarized as follows : 1. The bed rock geology is shown in Fig. 2 and Table 4. From the analysis of geomorphology and surface geology, the stable condition of the slope in the area can be shown as the mass movement geological map in Fig. 3. 2. From the chemical analyses or spring waters, the ground water can be subdivided into three types; bicarbonate, sulfate and sulfate-bicarbonate types on the basis of their dominant anions contents. From the water types, the said area is divided into 9 zones (A-1 zones) as shown in Fig. 8. 3. The main unstable slopes in this area as shown in Fig. 7 can be divided into the following three types : 1) Type of large-scaled sliding (2,3) exist in the area of the middle andesite group characterized by bicarbonate water. The rocks show weak wethering or alternation. 2) Type of middle-scaled sliding (4, 9) is related to the strongly wethered middle and upper andesite group characterized by sulfate type of water. 3) Type of small-scaled sliding (5, 6, 7, 8) is related to the weathered middle and upper andesite group and quartz-porphyry characterized by sulfate-bicarbonate water. 4. From the continuous observation and analyses of quality of river waters, a discontinuous abnormal change of patterns of electrolyte concentration was once recognized at the Kanayama river, a branch of the Ura river as shown in Fig. 10. These changes may be a marked phenomenon for prediction of debris flow.},
 pages = {1--34},
 title = {姫川水系浦川流域における斜面崩壊と土石流について : その1},
 volume = {4},
 year = {1982}
}