The Southern Hyogo Prefectural Earthquake which occurred on January 17, 1995, caused enormous damage such as collapse of buildings, fires, liquefaction of the ground, etc. It was the worst disaster since the Great Kanto Earthquake of 1923. The Geographical Survey Institute (GSI) started taking color aerial photographs immediately after the earthquake and drew an Earthquake Damage Map (First Edition; Map I) by photo interpretation, for the purpose of preparing fundamental data for investigation and restoration. Items included in Earthquake Damage Map I were “collapsed buildings and houses, ”“fires (burnt areas), ” “damaged roads and railroads, ” “slope failure and landslides, ” “liquefaction of the ground, ” “damaged quay, ”and“earthquake faults.”After that, other organaizations started similar investigations. In drawing the Earthquake Damage Map (Second Edition; Map II), the investigated areas were extended and other data were also used. Items included fundamentally followed Map I, although “collapsed buildings and houses” were newly classified into four categories, and two new items, “suspended sections of damaged roads and railroads, ” and “fissures” were added.
Earthquake Damage Map I drawn up and utilized immediately after the earthquake was highly esteemed. After that, investigations by other organizations showed earthquake damage similar to that in Earthquake Damage Map I. Therefore, the accuracy of Map I was confirmed. We examined the items included, and method of publication and prarctical use in the process of drawing up Earthquake Damage Map. It was found that photo interpretation of “fire (burnt areas), ” “damaged roads and railroads, ” and “liquefaction of the ground, ” was fairly easy, but that of “collapsed buildings and houses” and “slope failures and landslides” was comparatively difficult. Thus we recognized the limits of photo interpretation ability.
By drawing a distribution map of each kind of disaster based on the Earthquake Damage Maps, it was obvious that damaged buildings were mainly distributed in a zone from Suma Ward, Kobe City, to Nishinomiya City. We examined the relationship between damaged buildings, houses and landform. As a result, it was hypothesized that the primary factor in the damage concentration area was mainly earthquake motion because there was little influence of structures, landform and topography. After the Southern Hyogo Prefectural Earthquake we recognized that it is very important to collect and publish information on damage quickly in an emergency. The GIS and the Internet were utlized in this earthquake disaster. Therefore, it is expected that new technology will be utilized more extensively in the future.
