GIS-based database of historical liquefaction occurrences in the broader Aegean region, DALO v1.0

This paper presents the Database of historical Liquefaction Occurrences in the broader Aegean region (DALO). The database contains historical information regarding liquefaction manifestations, mainly in Greece and the broader Aegean region, that were collected during the last decade. In particular, descriptions of liquefaction manifestations triggered by 90 earthquakes since 1509 were collected and included into a database that was constructed using Ms-Access software. The database consists of six tables that are used for adding information into the database, while six forms have been created in order to present the dataset in a more suitable way. The outcome of this study is that 99% of liquefaction sites are located 0–100 m from a water body, and 94% consist of Holocene sediments and 6% of artificial fill. In addition, in order to present the data under a GIS environment, information in the database was exported into Google Earth kmz format. A web interface of DALO was developed and made available at the web site http://users.auth.gr/∼gpapatha/dalo.htm where three maps are presented regarding historical liquefaction occurrences. Photos and figures of the ground or structural failures have been uploaded as well, mainly for the events that occurred after 1950. This GIS-based dataset can be helpful, especially to decision makers and urban planners, as it can be used as a screening guide of liquefaction hazard for avoiding in advance liquefaction prone areas.