静岡県熱海市伊豆山地区の土砂災害現場の盛土と 土石流堆積物の地球化学・粒子組成分析

Autor: 北村晃寿, 岡嵜颯太, 近藤 満, 渡邊隆広, 中西利典, 堀 利栄, 池田昌之, 市村康治, 中川友紀, 森 英樹
Zdroj: Geoscience Reports of Shizuoka University; 2022, Issue 49, p73-86, 14p
Abstrakt: On July 3 2021, a debris flow caused by a landslide from an embankment occurred along the Aizome River in the Izusan area of Atami City, Shizuoka Prefecture, central Japan, and destroyed numerous houses and flowed into Sagami Bay. In this study, two samples of embankment, three debris flow deposits and two soil samples from around the Aizome River valley were analyzed for grain size, and geochemistry and grain compositions for each mud and sand particles. The most important result was the discovery of radiolarian chert fragments in black embankment sediments and debris flow deposits. These chert fragments are useful as tracer material for black embankment sediments. Furthermore, the radiolarian chert was found to have been deposited near the Permian/Triassic boundary and later into the Jurassic and Early Cretaceous. This is an important finding for identifying the source of black embankment sediments. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index