This map server contains the location of all cataloged earthquakes in Colorado. In addition to earthquakes, it also has the location of fault lines that are determined to have ruptured within the last 23 million years.
NOTE: THE EARTHQUAKE AND CENOZOIC FAULT AND FOLD MAP SERVER IS DOWN UNTIL FURTHER NOTICE. In the mean time, you may refer directly to the USGS’ Quaternary faults database map and the accompanying information page
Using the Map Server
Supported web browsers, although variations on the map may exist: Internet Explorer (IE 9 works best in Compatibility Mode); Firefox; Chrome; and Safari.
The map server offers different ways to access Colorado earthquake and fault information: it displays a map of earthquakes and Late Cenozoic faults within Colorado. It also allows quick identification of earthquake events by displaying a pop-up information box (called a maptip) that shows the date and magnitude of the event when resting a cursor over any of the earthquake symbols. The fault name will be shown when hovering the cursor over the line symbol for any structure. The map legend to the left of the screen shows the data layers and how each feature is symbolized.
The map server contains several ways to learn about an earthquake event from the connected databases. The databases contain a variety of information about each earthquake, such as: date, time, magnitude, location, depth and references. Similar reports are also generated for the faults. To see a report from the database, using the “Select” tool (white arrow), simply draw a box around the earthquake or fault in the map frame and click the “Selection Results” button in the top frame. Depending on your browser, you can also double click or CTRL+click on any of the events or structures and bring up the report. Clicking on the “Search” button on the top frame opens the search functions in the right browser pane. Use the drop down list of faults and folds to zoom to a particular structure or pull up its report. Earthquakes can be found by entering a start date and and end date. Click the “globe” icon on the Earthquake Search Results window to zoom to that event. Other useful tools, including additional selection and zooming tools, can be found by right-clicking on the map.
The database is periodically updated as new information on Colorado earthquakes become available. Users are encouraged to submit comments, corrections, and additions to Matt Morgan.
References for individual earthquakes and faults or folds are found on the generated report. To see a report from the database, using the ‘Select’ tool (white arrow), simply draw a box around the earthquake or fault in the map frame and click the “Selection Results” button in the top frame. Depending on your browser, you can also double click or CTRL+click on any of the events or structures and bring up the report.
The Colorado Geological Survey maintains an Earthquake Reference Collection that contains more than 500 sources on faulting and earthquakes in Colorado. Many of the references cited in the database are in the collection and can be viewed on-line or by appointment. To schedule an appointment please call 303-384-2655.
This publication should be cited as follows:
Morgan, M. L., 2017, Colorado Earthquake Map Server: http://dnrwebmapgdev.state.co.us/CGSOnline/
Kirkham, R. M., and Rogers, W. P., 1999, Colorado Earthquake Information 1867-1996: Colorado Geological Survey Bulletin 52, CD-ROM.
Widmann, B.L., Kirkham, R.M., and Rogers, W.P., 1998, Preliminary Quaternary fault and fold map and database of Colorado: Colorado Geological Survey Open Report 98-8, 331 p.
USGS Earthquake Catalog, https://earthquake.usgs.gov/earthquakes/