Globally there were 14,588 earthquakes of magnitude 4.0 or greater in 2015. This worldwide number is on par with prior year averages of about 40 earthquakes per day of magnitude 4.0, or about 14,500 annually. The 2015 number may change slightly as the final results are completed by seismic analysts at the USGS National Earthquake Information Center in Golden, Colorado.
In 2015, there were 19 earthquakes worldwide with a magnitude of 7.0 or higher. Since about 1900, the average has been about 18 earthquakes per year.
Earthquakes caused 9,612 deaths worldwide in 2015, a significant increase compared to 664 deaths in 2014. The majority of these fatalities – 8,964 people as reported by the United Nations Office for Coordination of Humanitarian Affairs – are attributed to the magnitude 7.8 earthquake that occurred on April 25 in Nepal. This was followed by another deadly earthquake with magnitude 7.3 on May 12 that killed an additional 218 people in Nepal. Deadly quakes also occurred in Afghanistan, Malaysia and Chile.
The biggest earthquake in the United States, a magnitude 6.9 southwest of Umnak Island, Alaska, occurred on July 27. This occurred in a remote location so there was no damage. In the central United States, seismicity continued to increase, with 32 earthquakes of magnitude 4.0 and greater in Kansas, Oklahoma and Texas in 2015 compared to 17 in 2014. Moderate earthquakes also occurred in Nevada and Arizona. A magnitude 5.0 east of Challis, Idaho, hit on January 3. In the United States, there were no fatalities caused by earthquakes.
The USGS monitors earthquakes around the world, responds rapidly to events of magnitude 5.0 or greater and for the final catalogs publishes earthquakes with a magnitude of 4.0 or greater. In the United States, earthquakes with magnitude 2.5 or greater are published.
To monitor earthquakes worldwide, the USGS NEIC receives data in real-time from about 1,800 stations in more than 90 countries. These stations include the 150-station Global Seismographic Network, which is jointly supported by the USGS and the National Science Foundation and operated by the USGS in partnership with the Incorporated Research Institutions for Seismology consortium of universities. Domestically, the USGS partners with 11 regional seismic networks operated by universities that provide detailed coverage for the areas of the country with the highest seismic risk.
Real-time information about earthquakes around the world can be found at earthquake.usgs.gov. Visit the USGS Significant Earthquakes Archive to see the complete list of notable earthquakes from 2015 and previous years. Read about other natural disasters that occurred in 2015 here.
More than 143 million residents living in the 48 contiguous states may potentially be exposed to damaging ground shaking from earthquakes. When the people living in the earthquake-prone areas of Alaska, Hawaii and U.S. territories are added, this number rises to nearly half of all Americans. The USGS and its partners in the multi-agency National Earthquake Hazard Reduction Program are continually working to improve earthquake monitoring and reporting capabilities via the USGS Advanced National Seismic System.