空中写真でみた液状化現象 : 新潟地震を例として  [in Japanese] Liquefaction Studied by Photointerpretation In Case of Niigata Earthquake  [in Japanese]

The Nihonkai Chubu Earthquake did great damage to humane life, ground and life line systems in extensive areas, mainly of Akita and Aomori Prefectures, along the coast of the Japan Sea. First of all, most striking damage was caused by the Tsunami which killed total of 104 victims and injured more than 300 people. Further, ground failure and accompanied severe damage to houses, rice fields, roads, railroad and water supply were observed dominantly in areas behind a sand dune and lowlands of alluvial plain along the coast of the Japan Sea. Most of ground failure in these areas, such as cracks, subsidence, uplift and sand eruption, is to be mostly due to liquefaction of subsurface layer caused by the Earthquake. While the Neogene distribution areas sustained minor damage to seacliff and hill side, which is characterized by ground failure like land slide, slump and fall. In this paper we describe several types of failure in each area sustained considerable damage, excluding those by the Tsunami. Our investigations how that concentration of damage is recognized in Alluvial distribution area on the Akita Coastal Plains. A clear relationship between damage distribution and subsurface geologyis also presented based upon analysis of Holocene microtopography.