Quick Start and User Guide
Table of Contents
Our webpages are designed to work in most current browser versions and one version previous. If you are having problems with the earthquake map, upgrading your browser will most likely resolve the issue.
Quick Tips Sheet
Use this one-page Quick Tips sheet (PDF) to quickly identify many of the features and controls on the earthquake map.
Help Contents
Help Using the New Interface
Navigation & Links Above Map
When you click on an earthquake in the Location column of the list, a new browser window or tab (depending on your browser settings) will open with the event page - details for the earthquake. To close the window/tab and go back to the map, simply click on the globe in the upper right corner.
Quickly switch the map and list to one of the “Jump to” areas listed above the map.
If you felt something that isn’t on the map/list, click on “Report it here” to access the Did You Feel It? form.
Settings
Click on the “Settings” button in the upper-right corner of the map to access these options.
- Save Settings - Saves the current filter criteria from the Control Panel, the list sort orders, map information (base layer and overlays) and current map view (zoom location). The pop-up window allows you to save the settings using a cookie or by adding a bookmark in your browser.
- Revert to Saved Settings - Resets the current map view and list to your Saved Settings.
- Clear Saved Settings - Removes the Saved Settings and restores the default settings.
Map Layers
Click on the “Map Layers” button in the upper-right corner of the map to access these options.
- Base Layer - The map base layer may be changed. One base layer may be selected at a time and determines which type of map is displayed. Different base layers allow different levels of zooming. The street map and aerial map allow you to zoom in closer than the topography map.
- Map Overlays - Multiple overlays may be selected, showing or hiding additional information such as earthquakes or faults. Please note: not all overlays are available at all zoom levels. For example, faults are not available at max zoom.
Legend
The map legend is accessed by clicking on the "Legend" button in the upper-right corner of the map. The earthquake circle size denotes magnitude and the circle color denotes how recent the event is.
Data Feed
The Data Feed is a menu selection of several different data feeds to view in the map/list interface. The default is set to the feed with the smallest number of events so that the map and data load as quickly as possible. The Control Panel filters will change to match the Data Feed extents when a different Data Feed is selected EXCEPT the "Earthquakes to Display" filter which will remain set to 300 until the user changes it. The data can be further filtered using the other Control Panel tools.
The Auto-Update check box allows you to enable or disable automatic updates to the list and map. The update interval is 1 minute for the 7-day/M2.5+ feed, 5 minutes for the 7-day/All magnitudes feed, and 15 minutes for all the 30-day feeds.
Summary
The Summary panel displays general information, such as number of earthquakes found and update time.
Updated
Earthquakes are updated in realtime every x minutes based on the selected data feed. The most recent update is listed here. When earthquakes update they are replotted on the map with the most recent events visible on top.
Numbers of Earthquakes
- First Number - Number of earthquakes in selected data feed.
- Second Number - Number of earthquakes that meet the Control Panel criteria in the current map area in view.
- Third Number - Number of earthquakes actually displayed on the map and in the list. This number may be smaller than the second number because of the limit set by “Earthquakes to Display” in the Control Panel.
Download Earthquakes
Earthquake information may be downloaded in a variety of formats. Select a format from the drop-down list and click “Download” to receive the file. Only events that meet the current filter criteria in the Control Panel are downloaded (excluding the “Earthquakes to Display” limit).
- KML (Google Earth) - Chooose KML to download a Google Earth file with filtered earthquake information. You will need the Google Earth viewer, web plugin or another KML reader to open this file.
- CSV (Spreadsheet) - Use the CSV download to obtain a comma separated list of filtered earthquakes.
Depending on your browser, downloading earthquake information may require Flash. This requirement is a technical limitation in order to provide the best possible performance to the largest possible group of people.
Control Panel
Earthquakes may be filtered to find events with specific parameters. Filtering earthquakes reduces the number of events displayed on the map and listing, improving performance and making it easier to find what you need.
Timezone
You may choose to have event times displayed in UTC or in local time using the system time of your device. If your system time is not set correctly, the event times displayed will not be correct.
Earthquakes to Display
Limit the number of filtered events that are displayed on the map and
listing. 300 events is the default. Larger numbers may cause performance issues, up to and including
causing your browser to crash, so use caution with higher values!
This filter does not affect how many events are downloaded with the Download tool.
Earthquake Age
Show earthquakes within this time range.
Magnitude
Show earthquakes within this magnitude range.
Depth
Show earthquakes within this depth range. When the slider is set at zero kilometers all earthquakes with a depth less than zero will display.
Intensity
Show earthquakes with a maximum Modified Mercalli Intensity within this range.
Interacting with the Earthquake Map
The Earthquake Map interface displays earthquake events as sized and
colored circles.
By default, most recent events are displayed on top of older events.
The latitude-longitude location of the cursor on the map is shown on the
bottom-left of the map.
If the selected data feed returns more earthquakes than the “Earthquakes
to Display” limit allows, you can sort events in the list view to
change which earthquakes are displayed first, or you can increase the number of earthquakes to display.
Panning the Map
Click and drag on the map to pan. Alternatively, use the arrow buttons in the upper-left corner of the map. The default map view shows from -89.5 South to 89.5 North, so you will have to pan the map to see the poles. Alternatively, you can download the KML file and view the map in Google Earth or some other KML reader.
Zooming the Map
To zoom in on a specific point, double click on the map.
To zoom in on an area, use the magnifier button on the left side (or
simply hold shift) and drag a box around the desired region.
To zoom in general, use the slider and +/- buttons on the left side of the
map.
Keyboard Shortcuts
Zooming Hold the shift key down and drag the cursor to select an area to zoom to.
Panning
Click on map and then use arrow keys to pan map. Click off map to disable.
Click on map and then use + and - keys to zoom in and out. Click off map
to disable.
Selecting Earthquakes
Mousing over a circle on the map pops up information about the magnitude,
date and time of the event.
Clicking on a circle on the map selects an earthquake event.
The selected earthquake is highlighted as green on the map and in the
list, and brought to the front on the map, regardless of how recent it
was.
To view detailed information for that event, click on the Location text
for the highlighted event in the list.
Interacting with the Earthquake List
The Earthquake List displays tabular information about events in the selected data feed that meet the current filtering criteria in the Control Panel. Only events that appear on the map are listed.
Sorting Earthquake List
To sort the earthquaking list, simply click on the desired heading
(“M” for magnitude, “Location” for name, etc.).
Repeated clicking toggles between ascending and descending order.
If the current filter returns more earthquakes than the “Earthquakes
to Display” limit allows, events that are at the top of your sort
are displayed first.
Selecting Earthquakes
Clicking anywhere on a row (except the name) selects that earthquake event. The selected earthquake is highlighted as green in the list and on the map, and is brought to the front on the map, regardless of how recent it was.
Viewing Earthquake Information
Clicking on an event’s Location text opens the event page in a separate window.
Known Issues
- If you leave your browser window open with the map for multiple days or weeks, the auto-update may stop working, and you may get an error message.
- The default map view shows -73.9 degrees South to 78.8 degrees North. If there is a rare earthquake to the north or south of those latitudes, you will not see it on the map unless you pan the map. The total number of earthquakes in the past 30 days in the Summary box will include all earthquakes all the way to the Poles, but the other numbers may be less than that if an earthquake is not showing on the map because of it's Polar location.
Information Contents
- General
- Data Sources and Contributors
- Map Information and Data Sources
-
Network Contacts
- NEIC
- Alaska
- West Coast Alaska Tsunami Warning Center/NOAA/NWS
- Cooperative New Madrid Seismic Network
- Inter-Mountain West Seismic Networks
- Hawaii
- Pacific Tsunami Warning Center
- Northeast
- Northern California Seismic Network
- Pacifc Northwest Seismic Network
- Puerto Rico Seismic Network
- Southern California Seismic Network
General Information
Why is the earthquake that was reported/recorded by network X, or that I felt, not on the map/list? and other Frequently Asked Questions (FAQ) about the Latest Earthquakes information.
USGS Earthquake Magnitude Policy
The earthquake map projection is Web Mercator, and the reference model is WGS-84.
Search results are limited to 20,000. Any search that exceeds this limit will result in an error.
Realtime Earthquake Data Sources & Contributing Networks
US, International, and Offshore Regions
- National Earthquake Information Center (NEIC)
- West Coast & Alaska Tsunami Warning Center
- Pacific Tsunami Warning Center
Alaska
Central and Southeastern US
Cooperative Central and Southeast U.S. Seismic Network CERI/SLU/VPI/USC/…
The participating institutions are:
- Delaware Geological Survey
- Maryland Geological Survey Seismic Network
- University of Memphis - Center of Earthquake Research and Information (CERI)
- Saint Louis University (SLU)
- University of Tennessee/Tennessee Valley Authority - Joint Institute for Energy and Environment
- University of South Carolina (USC) Seismology
- Virginia Tech (VPI)
Hawaii
Nevada
Northeast
Lamont-Doherty Cooperative Seismographic Network (LCSN)
The participating institutions are:
- Lamont-Doherty Earth Observatory of Columbia University
- Geological Survey of Canada
- Ohio Seismic Network
- Southern Ontario Seismic Network
Northern California
- Northern California Seismic Network (NCSN)
-
Berkeley Digital Seismic Network (BDSN)
The participating institutions are:
Pacific Northwest
Pacific Northwest Seismograph NetworkThe participating institutions are:
- Univ. of Washington, Dept. of Earth and Space Sciences
- Oregon State University Geophysics Group
- University of Oregon Department of Geology
Puerto Rico
Southern California
Southern California Seismic Network (SCSN): a cooperative project.
The participating institutions are:
- U.S. Geological Survey, Pasadena
- California Institute of Technology, Seismological Laboratory
- University of California, San Diego
- Data archive at Southern California Earthquake Data Center (SCEDC)
Utah and Yellowstone
All members of the …
Map Information and Data Sources
Map Software
- USGS Topographic map tiles created with ArcGIS 10 for Desktop.
- Interactive web interface powered by OpenLayers.
Topographic Data
This data was acquired from the General Bathymetric Chart of the Oceans (GEBCO) project at: http://www.gebco.net/data_and_products/gridded_bathymetry_data/. The data in its original form is 30 arc-second bathymetry data for the entire globe. Land data is supplemented in most cases by Shuttle Radar Topography Mission (SRTM30) digital elevation model. For detailed cache levels, this data was resampled dynamically by ArcGIS Desktop software to give users more elevation detail.
Street/Aerial Data
Street and Aerial data, imagery and map information provided by MapQuest, OpenStreetMap and contributors, CC-BY-SA. Green boundaries usually just offshore are “administrative boundaries”. Please see the OpenStreetMap website for more information on the basemaps they provide.
Plate Boundary Data
This data was acquired from the Peter Bird Plate Boundary Dataset. Information about this data can be found at: http://peterbird.name/publications/2003_PB2002/2003_PB2002.htm.
NOTE: Included plate boundaries were chosen appropriately based on scale.
Water Data
The river and lakes data for these maps came from GMT and its pre-built dataset. The detailed shoreline data that is present in coastal maps was acquired from NOAA’s Coastal Geospatial Data Project. More information can be found at: http://coastalgeospatial.noaa.gov/gis_files/shoreline/shoreline_data_dictionary.html
State and International Boundaries
- State boundaries provided by The National Map
- International boundaries provided by GEO.DATA.gov
Placename Data
The placenames were derived from US Census data, such as from http://www.census.gov/geo/www/gazetteer/places2k.html. International places were gathered from a specially created USGS catalog. Selected places were based on minimum population values that were specified for each particular region. If there are too many places on any map, a separation distance algorithm was used to limit the number of places that appear on the map. If no places appeared on the map, a lower population threshold was used to plot smaller places.
Faults
The data used for these features was acquired from the Hazard Faults Database for the United States. See the Quaternary Fault and Fold Database of the United States for more information.
Known hazardous faults and fault zones in California and Nevada
The known active fault segments in California and Nevada can be seen in Figure 25 of USGS Open-File Report 96-532: National Seismic Hazard Maps, June 1996: Documentation" by Arthur Frankel, Charles Mueller, Theodore Barnhard, David Perkins, E.V. Leyendecker, Nancy Dickman, Stanley Hanson, and Margaret Hopper.
For northern California, the potential sources of earthquakes larger than magnitude 6 are documented in Open-File Report 96-705 by the Working Group on Northern California Earthquake Potential (chaired by Jim Lienkaemper).
For the state as a whole, see “Probabilistic seismic hazard assessment for the State of California” by Petersen, M. D., Bryant, W.A., Cramer, C.H., Cao, T., Reichle, M.S., Frankel, A.D., Lienkaemper, J.J., McCrory, P.A., and Schwartz, D.P, 1996 (California Division of Mines and Geology Open-File Report 96-08; [published jointly as] U.S. Geological Survey Open-File Report 96-706).
The faults and fault zones described in these reports are known to have been active in the last 2 million years and are thought to pose a measurable hazard.
For California the faults on the individual zoomed-in and special maps come from the three categories of faults believed to have been active in the last 700,000 years shown on the “Preliminary Fault Activity Map of California” by C.W. Jennings (1992, California Division of Mines and Geology Open-File Report 92-03). This map has been superseded by Jennings, C.W., 1994, Fault activity map of California and adjacent areas, with locations and ages of recent volcanic eruptions: California Division of Mines and Geology, Geologic Data Map No. 6, map scale 1:750,000.
For Nevada the faults on the individual zoomed-in and special maps come from USGS Open-File Report 96-532 mentioned above.
For more information on files and images discussed above visit the 1996 Documentation Page
Highways and Roads
Interstate Highway data is from the National Atlas of the United States.
Global and US Hazard
- Global hazard is from the Global Seismic Hazard Assessment Program (GSHAP)
- US hazard is from the USGS Seismic Hazard Mapping Project (NSHM)
Network Contacts
National Earthquake Information Center (NEIC)
U.S. Geological SurveyNational Earthquake Information Center
Box 25046, DFC, MS 967
Denver, Colorado 80225
Earthquake Information Line: 303-273-8500 (24x7 Opertions)
Fax: 303-273-8450
Web Page: http://earthquake.usgs.gov/regional/neic/
E-mail: sedas@neis.cr.usgs.gov
Alaska Earthquake Information Center (AEIC)
Alaska Earthquake Information Center (AEIC)Geophysical Institute
University of Alaska Fairbanks
903 Koyukuk Drive
Fairbanks, AK 99775-7320
Voice: 907-474-7320
Fax: 907-474-7125
Web Page: http://www.aeic.alaska.edu/
E-mail: webmaster@giseis.akaska.edu
West Coast and Alaska Tsunami Warning Center/NOAA/NWS
West Coast and Alaska Tsunami Warning Center/NOAA/NWS910 S. Felton St.
Palmer, AK 99645
Web Page: http://wcatwc.arh.noaa.gov/
E-mail: wcatwc@wcatwc.gov
Cooperative New Madrid Seismic Network
Center for Earthquake Research and InformationCampus Box 526590
The University of Memphis
Memphis, TN 38152
Voice: 901-678-2007
Fax: 901-678-4734
Web Page: http://www.ceri.memphis.edu/
E-mail: withers@ceri.memphis.edu
Inter-Mountain West Seismic Networks
Earthquake Studies OfficeMontana Bureau of Mines and Geology
1300 West Park Street
Butte, MT 59701-8997
Voice: 406-496-4332
Fax: 406-496-4451
Web Page: http://mbmgquake.mtech.edu/
E-mail: mstickney@mtech.edu
University of Nevada, Reno
Reno, Nevada
Voice: 775-784-4975
Fax: 775-784-4165
Web Page: http://www.seismo.unr.edu/
135 South 1460 East
Salt Lake City, Utah 84112-0111
Voice: 801-581-6274
Fax: 801-585-5585
Web Page: http://www.seis.utah.edu/
E-mail: webmaster@seis.utah.edu
Hawaiian Volcano Observatory Network
U.S. Geological SurveyHawaiian Volcano Observatory
P O Box 51
Hawaii National Park, Hawaii 96718
Voice: 808-967-7328
Fax: 808-967-8890
Web Page: http://hvo.wr.usgs.gov/
Web Page: http://elsei.wr.usgs.gov/results/seismic/recenteqs/
E-mail: hvowebmaster@hvo.wr.usgs.gov
Pacific Tsunami Warning Center
US Dept of Commerce91-270 Fort Weaver Road
EWA Beach, HI 96706-2928
Voice: 808-689-8207
Web Page: http://ptwc.weather.gov
E-mail: webmaster@ptwc.noaa.gov
Northeast
Lamont-Doherty Cooperative Seismographic Network (LCSN)Lamont-Doherty Earth Observatory of Columbia University
Palisades, NY 10964
Voice: 845-365-8365
Fax: 845-365-8150
Web Page: http://www.ldeo.columbia.edu/LCSN/
E-mail: jha@ldeo.columbia.edu
Department of Geology and Geophysics, Boston College
381 Concord Road Weston, MA 02493-1340
Voice: 617-552-8300
Fax: 617-552-8388
Web Page: http://www.bc.edu/bc_org/avp/cas/wesobs/
E-mail: weston.observatory@bc.edu
Northern California Seismic Network
U.S. Geological SurveySeismology Section
345 Middlefield Road - MS 977
Menlo Park, CA 94025
Earthquake Info: 650-329-4025
Voice: 650-329-4085
Fax: 650-329-5163
Web Page: http://earthquake.usgs.gov/
E-mail: ncsn@andreas.wr.usgs.gov
207 McCone Hall
U.C. Berkeley
Berkeley, CA 94720-4760
Earthquake Info: 510-642-2160
Voice: 510-642-3977
Fax: 510-643-5811
Web Page: http://www.seismo.berkeley.edu/
E-mail: www@seismo.berkeley.edu
Pacific Northwest Seismic Network
Univ. of Washington, Dept. of Earth and Space SciencesBox 351310
Seattle, WA 98195-1310
Earthquake Info: 206-543-7010
Voice: 206-685-8180 (lab) or 206-543-1190 (department)
Fax: 206-543-0489
Web Page: http://www.ess.washington.edu/SEIS/PNSN/welcome.html
E-mail: seis_info@ess.washington.edu
Puerto Rico Seismic Network
Puerto Rico Seismic NetworkDepartment of Geology
University of Puerto Rico at Mayagüez
PO Box 9017
Mayagüez, PR 00681-9017
Voice: 787-833-8433
Fax: 787-265-1684
Web Page: http://redsismica.uprm.edu/english/
E-mail: staff@redsismica.uprm.edu
Southern California Seismic Network
Southern California Seismic NetworkU.S. Geological Survey - Caltech Seismological Laboratory
Pasadena, California
EQ Info: 626/395-6977
Voice: 626/583-7823 or 626/395-6919
Fax: 626/583-7827
Web Page: http://earthquake.usgs.gov/regional/sca/
Web Page: http://www.seismolab.caltech.edu/
Disclaimer Contents
Disclaimers
“Missing” Earthquakes?
The maps and lists show events which have been located by the USGS and contributing agencies within the last 30 days. They should not be considered to be complete lists of all events in the US and adjacent areas and especially should not be considered to be complete lists of all events M4.5+ in the world.
In most cases, we locate and report on earthquakes worldwide of magnitude 5.0 and larger in 30 minutes or less. Additionally, we locate and report on earthquakes magnitude 4.0 and larger within the contiguous US and populated regions of Alaska within 30 minutes. Earthquakes of magnitude 2.0 or greater within the US and populated regions of Alaska are often rapidly reported if they occur within the region of a contributing local seismic network.
We may not rapidly locate earthquakes smaller than 5.0 outside the US unless they have caused significant damage or are widely felt. Earthquakes this small rarely cause significant damage. At times, some other agency may report an earthquake with a larger magnitude than what we compute from our data, especially for non-US events near magnitude 5.0. If our magnitude for the event is less than magnitude 5.0, we may not issue a rapid report for it.
Earthquakes occurring outside the US and smaller than about magnitude 4.5 can be difficult for the USGS to locate if there are not enough data. The USGS continues to receive data from observatories throughout the world for several months after the events occur. Using those data, we add new events and revise existing events in later publications. For a description of these later publications and the data available, see Scientific Data.
If you think there is a missing earthquake on our maps and lists, there possibly is. Please see the national and regional links for the area of interest on these webpages:
Magnitudes
The magnitude which the USGS considers official for this earthquake is indicated at the top of this page. This was the best available estimate of the earthquake’s size, at the time that this page was created. Other magnitudes associated with web pages linked from here are those determined at various times following the earthquake with different types of seismic data. Although they are legitimate estimates of magnitude, the USGS does not consider them to be the preferred (“official” magnitude for the event.
Placenames/Labels
The list of reference places from the earthquake epicenter is automatically created using a database of placenames and an algorithm that chooses several locations as references. The number of placenames depends on the location of the earthquake. We use the GeoRef database and supplement it with additional placenames for locations distant from any cities (such as ocean ridges).
As an agency of the U.S. Government, we are expected to use the names and spellings approved by the U.S. Board on Geographic Names. Any requests to approve additional names should be made to the U.S. Board on Geographic Names. For more information, see their website at http://earth-info.nga.mil/gns/html/.
The region name is an automatically generated name based on the Flinn-Engdahl (F-E) seismic and geographical regionalization scheme. The boundaries of these regions are defined at one-degree intervals and therefore differ from irregular political boundaries. For example, F-E region 545 (Northern Italy) also includes small parts of France, Switzerland, Austria and Slovenia and F-E region 493 (Chesapeake Bay Region) includes all of the State of Delaware, plus parts of the District of Columbia, Maryland, New Jersey, Pennsylvania and Virginia. Beginning with January 2000, the 1995 revision to the F-E code has been used in the QED and PDE listings. This revision includes 28 additional regions, which were defined by subdividing larger regions to provide better coverage for Northwest Africa, Southeast Asia and seismic zones along oceanic ridges. In recent years, additional polygons have been defined in some areas to agree better with irregular political boundaries and to provide some additional detail.
See http://earthquake.usgs.gov/learn/topics/flinn_engdahl.php
References
- Young, J.B., Presgrave, B.W., Aichele, H., Wiens, D.A. and Flinn, E.A., 1996, The Flinn-Engdahl Regionalisation Scheme: the 1995 revision, Physics of the Earth and Planetary Interiors, v. 96, p. 223-297.
- Flinn, E.A., Engdahl, E.R. and Hill, A.R., 1974, Seismic and geographical regionalization, Bulletin of the Seismological Society of America, vol. 64, p. 771-993.
- Flinn, E.A., and Engdahl, E.R., 1965, A proposed basis for geographical and seismic regionalization, Reviews of Geophysics, vol. 3, p. 123-149.