Integrated Web-based Oracle and GIS Access to Natural Hazards Data

The National Geophysical Data Center (NGDC) catalogs information on tsunamis, significant earthquakes, and volcanoes including effects such as fatalities and damage. NGDC also maintains a large collection of geologic hazards photos. All of these databases are now stored in an Oracle relational database management system (RDMS) and accessible over the Web as tables, reports and interactive maps. Storing the data in a RDMS facilitates the search for earthquake, tsunami and volcano data related to a specific event. For example, a user might be interested in all of the earthquakes greater than magnitude 8.0 that have occurred in Alaska. If the earthquake triggered a tsunami, the user could then directly access related information from the tsunami tables without having to run a separate search of the tsunami database. Users could also first access the tsunami database and then obtain related significant earthquake and volcano data. The ArcIMS-based interactive maps provide integrated Web-based GIS access to these hazards databases as well as additional auxiliary geospatial data. The first interactive map provides access to individual GIS layers of significant earthquakes, tsunami sources, tsunami effects, volcano locations, and various spatial reference layers including topography, population density, and political boundaries. The map service also provides ftp links and hyperlinks to additional hazards information such as NGDC's extensive collection of geologic hazards photos. For example, a user could display all of the significant earthquakes that have occurred in California and then by using a hyperlinks tool, display images showing damage from a specific earthquake such as the 1989 Loma Prieta event. The second interactive map allows users to display related natural hazards GIS layers. For example, a user might first display tsunami source locations and select tsunami effects as the related feature. Using a tool developed at NGDC, the user can then select a specific tsunami event and automatically display the tsunami effect locations related to that event. The user could also select significant earthquake events and display tsunami events related to specific quakes.