THE COLORADO EARTHQUAKE MAP SERVER

The Colorado Geological Survey has compiled a database of over 570 earthquakes in Colorado from the years 1870 through 2005. The data include information such as date, location, time, magnitude, and intensity. To quickly disseminate earthquake information to the public, we transformed this non-spatial database into a searchable map layer that can be displayed along with other spatial information. The end result is a user-friendly, internet-based Geographic Information System (GIS) that can be easily explored or used for analysis.

Utilizing the map server interface, the end-user can browse the earthquake information by clicking on an event and viewing a report generated from a relational database. Where available, isoseismal maps are included on the event report. Earthquake locations are subdivided into magnitude (mechanically instrumented or estimated) and intensity (felt reports); event symbols are graduated and color-coded depending on earthquake strength. Moving the map cursor over an earthquake point location generates a pop-up “maptip” that displays the event magnitude and date. Locations of active and inactive seismic stations are also displayed. The end-user can activate and query other map layers such as faults, trench locations, topography, and cultural information.

Internet map server applications revolutionized the way data is updated, viewed, and distributed to the public. Once added to a map server, non-spatial databases can be manipulated and updated in near real-time to allow quick dissemination to the end-user. This allows the end-user to obtain newly acquired information from a single application, that previously, was much more time-consuming and laborious.

The Colorado Earthquake Map Server is available for viewing on line at http://geosurvey.state.co.us.