著者
岩松 暉
出版者
古今書院
雑誌
地理 (ISSN:05779308)
巻号頁・発行日
vol.59, no.5, pp.52-60,図巻頭5, 2014-05
著者
岩松 暉
出版者
日本自然災害学会
雑誌
自然災害科学 (ISSN:02866021)
巻号頁・発行日
vol.16, no.2, pp.107-111, 1997-08-30
被引用文献数
3

Severe debris flow disaster occurred along the Harihara River, Izumi City, Kagoshima Prefecture at midnight of June 10,1997. 21 persons were killed and 18 houses were destroyed by the debris flow. Pleistocene volcanic breccias are widely distributed in the vicinity of the Harihara district. Matrices of these rocks have been greatly altered to very soft clay by superficial weathering. And thick slope sediments which consist of talus deposits with huge boulders and core stones of onion structure crop out in the landslide area. Collapsed slope sediments rushed into farm pond beneath the slope, and water-saturated debris changed into debris flow.
著者
和田 卓也 井上 誠 横田 修一郎 岩松 暉
出版者
一般社団法人日本応用地質学会
雑誌
応用地質 (ISSN:02867737)
巻号頁・発行日
vol.36, no.5, pp.349-358, 1995-12-10
被引用文献数
10

Downward infiltration of rainwater within the Quaternary pyroclastic plateau have been studied by using continuous and automatical survey of electric prospecting and chemical analysis of seepage water from the foot of the plateau. Reduction of apparent resistivity and its downward extension are recognized within the plateau just after the heavy rain. This means the existence of downward infiltration of rainwater. However, the style of infiltration is various, and it seems to be strongly influenced by rainfall condition and surface humus soils. Downward velocity of the infiltration is estimated to be 60 meters/12 hours, and this value is too rapid compared with the well-known value of 1〜3 mm/day. Probably, two types of downward infiltration may co-exist because of cooling joints or pipe structures within the pyroclastic flow deposits. On the other hand, chemical analysis of seepage water shows that the concentration of ions may change depending on that of rainfall. This may support the result mentioned above of the rapid velocity.