Users of U.S. Geological Survey earthquake information now have an additional way to access that information. By viewing worldwide historic earthquake data with Google Earth mapping technology, users can quickly and easily visualize scientific information in a geographic context.

Although the huge databases of earthquake occurrences have been available publicly for a long time, the interactive graphic display of Google Earth makes it easy to understand the context and significance of each quake. Popup windows in the application give the user more information about the earthquake's magnitude, date, location and depth.

USGS and Google signed an agreement to publish historic earthquake data from the Advanced National Seismic System catalog as a "built-in" layer, accessible directly from the Google Earth viewer. Now, it is simply a matter of toggling a check box to turn on the earthquake layer, similar to roads and other geographic features. The new layer includes historic earthquakes since 1900, and USGS real-time earthquakes are now accessible as a hyperlink from within Google Earth. If the layer is checked, users will see a sprinkling of dots across the globe, each marking an earthquake epicenter

Google Earth was accessible from the USGS earthquake Web site (http://earthquake.usgs.gov), but users had to purposefully seek out the data feeds or stumble on them while browsing the USGS Web site. The ease of finding USGS earthquake data directly within the Google Earth viewer makes complex scientific data much more accessible and understandable to more people worldwide.

To display the earthquake locations in the Google Earth viewer, go to the layers menu, and look in the folder "Places of Interest." Open the "Geographic Features" folder and click on "Earthquakes."

In late 2004, USGS began offering a real-time earthquake layer for Keyhole Viewer (now Google Earth), one of the first applications for visualizing real-time data in a virtual globe environment. Development continued, and UCLA professor Peter Bird's plate boundaries were added to give the earthquakes context in a global setting. Later, USGS began offering a complementary layer of historic earthquakes, giving a continuous earthquake catalog from 1970 to the present, viewable in an interactive environment.

"We look forward to further collaboration with Google to streamline the presentation of earthquake data in Google Earth," USGS geologist and Web master Scott Haefner said. "The ultimate goal is to integrate real-time earthquakes as a separate built-in layer, and in the longer run, our agreement with Google could serve as a template for incorporating other authoritative USGS data such as streamflow data, landslides, mineral distributions, and many more."

For additional information, contact Scott Haefner, USGS, at (650) 329-4854, or Leslie Gordon, USGS, at (650) 329-4854.