World Library  
Flag as Inappropriate
Email this Article

Earthquake swarm

Article Id: WHEBN0000868056
Reproduction Date:

Title: Earthquake swarm  
Author: World Heritage Encyclopedia
Language: English
Subject: Lōʻihi Seamount, 1995 Gulf of Aqaba earthquake, Swarm behaviour, Aftershock, Volcano tectonic earthquake
Collection: Earthquake Swarms, Tectonics
Publisher: World Heritage Encyclopedia

Earthquake swarm

February 2008 swarm near Mexicali.

Earthquake swarms are events where a local area experiences sequences of many earthquakes striking in a relatively short period of time. The length of time used to define the swarm itself varies, but the United States Geological Survey points out that an event may be of the order of days, weeks, or months.[1] They are differentiated from earthquakes succeeded by a series of aftershocks by the observation that no single earthquake in the sequence is obviously the main shock. Earthquake swarms are one of the events that typically precede eruptions of volcanoes.


In the United States there were the 2008 Reno earthquakes that began in February and ended in November.[2] Between February and April the swarm produced more than 1,000 quakes of small magnitude, although the largest measured 4.7.

Another example was that affecting a Spanish island in the eastern Atlantic during the 2011–12 El Hierro eruption. From July 2011 until October 2011, hundreds of small earthquakes were measured. The accumulated energy released by the swarm increased dramatically on 28 September.[3] The swarm was due to the movement of magma beneath the island, and on 9 October indications of a submarine volcanic eruption were detected.[4]

Between February 2011 and December 2011 more than 500 earthquakes were recorded during the 2011 Christchurch earthquakes, with 31 of them greater than magnitude 5.

Near Mexicali, along the Cerro Prieto Fault, over 500 quakes and aftershocks occurred during a two-week period in February 2008.[5]

In 2013, the Santa Cruz Islands had been experiencing a large earthquake swarm with many magnitude 5 and 6 earthquakes occurring since January and continuing into February. This later turned out to be a series of foreshocks that led up to the 8.0 2013 Solomon Islands earthquake on February 6.

In 2014, an area near the California/Oregon/Nevada borders experienced more than 800 small earthquakes over a period of around three months. [6] More than 550 quakes were on magnitude 2.0 or larger. [7]

See also


  1. ^ USGS. "Earthquake Swarms at Yellowstone".  
  2. ^ Ashley Powers; Thomas H. Maugh II. "Swarm of earthquakes shakes Reno area".  
  3. ^
  4. ^ Bernardo Marin; R. Mendez (October 11, 2011). "La erupción volcánica submarina de El Hierro libera magma y gases en el océano".  
  5. ^ Sandra Dibble. "Ground stays still, but residents in quake area rattled".  
  6. ^ Associated Press. "As the Earth's crust stretches, swarm of earthquakes tickles remote Nevada desert".  
  7. ^ Curtis Skinner. "Nevada earthquake swarm increases chance of larger quake".  
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.