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Earthquake Energy Release

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Earthquake Facts and Statistics

Frequency of Occurrence of Earthquakes

Magnitude Average Annually
8 and higher 1
7 - 7.9 15
6 - 6.9 134
5 - 5.9 1319
4 - 4.9 13,000
(estimated)
3 - 3.9 130,000
(estimated)
2 - 2.9 1,300,000
(estimated)

Based on observations since 1900. 
These numbers have been recently updated, based on data from the Centennial catalog (from 1900 to 1999) and the PDE (since 2000). 
Based on observations since 1990.

Magnitude vs. Ground Motion and Energy

Magnitude Change Ground Motion Change 
(Displacement)
Energy Change
1.0 10.0 times about 32 times
0.5 3.2 times about 5.5 times
0.3 2.0 times about 3 times
0.1 1.3 times about 1.4 times

This table shows that a magnitude 7.2 earthquake produces 10 times more ground motion than a magnitude 6.2 earthquake, but it releases about 32 times more energy. The energy release best indicates the destructive power of an earthquake. See: How much bigger is a magnitude 8.7 earthquake than a magnitude 5.8 earthquake?

The USGS estimates that several million earthquakes occur in the world each year. Many go undetected because they hit remote areas or have very small magnitudes. The NEIC now locates about 50 earthquakes each day, or about 20,000 a year.

As more and more seismographs are installed in the world, more earthquakes can be and have been located. However, the number of large earthquakes (magnitude 6.0 and greater) has stayed relatively constant. See: Are Earthquakes Really on the Increase?


Number of Earthquakes Worldwide for 2000 - 2012 
Located by the US Geological Survey National Earthquake Information Center

Magnitude 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
8.0 to 9.9 1 1 0 1 2 1 2 4 0 1 1 1 0
7.0 to 7.9 14 15 13 14 14 10 9 14 12 16 23 19 1
6.0 to 6.9 146 121 127 140 141 140 142 178 168 144 149 185 13
5.0 to 5.9 1344 1224 1201 1203 1515 1693 1712 2074 1768 1896 2025 2278 155
4.0 to 4.9 8008 7991 8541 8462 10888 13917 12838 12078 12291 6805 10345 13245 448
3.0 to 3.9 4827 6266 7068 7624 7932 9191 9990 9889 11735 2905 4324 2786 67
2.0 to 2.9 3765 4164 6419 7727 6316 4636 4027 3597 3860 3014 4624 3613 86
1.0 to 1.9 1026 944 1137 2506 1344 26 18 42 21 26 39 46 5
0.1 to 0.9 5 1 10 134 103 0 2 2 0 1 0 1 0
No Magnitude 3120 2807 2938 3608 2939 864 828 1807 1922 17 24 19 4
Total 22256 23534 27454 31419 31194 30478 29568 29685 31777 * 14825 * 21554 * 22193 * 779
Estimated
Deaths
231 21357 1685 33819 228802 88003 6605 712 88011 1790 320120 21404 0

Starting in January 2009, the USGS National Earthquake Information Center no longer locates earthquakes smaller than magnitude 4.5 outside the United States, unless we receive specific information that the earthquake was felt or caused damage.

The values in the tables for the most recent years may fluctuate due to magnitude updates during the review process.

Number of Earthquakes in the United States for 2000 - 2012 
Located by the US Geological Survey National Earthquake Information Center

Magnitude 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
8.0 to 9.9 0 0 0 0 0 0 0 0 0 0 0 0 0
7.0 to 7.9 0 1 1 2 0 1 0 1 0 0 1 1 0
6.0 to 6.9 6 5 4 7 2 4 7 9 9 4 8 3 1
5.0 to 5.9 63 41 63 54 25 47 51 72 85 58 74 51 2
4.0 to 4.9 281 290 536 541 284 345 346 366 432 288 646 345 21
3.0 to 3.9 917 842 1535 1303 1362 1475 1213 1137 1486 1492 3584 1820 42
2.0 to 2.9 660 646 1228 704 1336 1738 1145 1173 1573 2379 4131 2918 75
1.0 to 1.9 0 2 2 2 1 2 7 11 13 26 39 46 5
0.1 to 0.9 0 0 0 0 0 0 1 0 0 1 0 1 0
No Magnitude 415 434 507 333 540 73 13 22 20 14 12 14 4
Total 2342 2261 3876 2946 3550 3685 2783 2791 3618 * 4262 * 8495 * 5199 * 150
Estimated
Deaths
0 0 0 2 0 0 0 0 0 0 0 0 0

* As of 02 February 2012

Earthquake Information for the 1990s

Graphs of Earthquake Statistics

We detect, but generally do not locate, about 50 mine blasts (explosions) throughout the United States on any given business day. These blasts typically occur between noon and 6 PM local time Monday through Saturday. Of these, about one event every two days is large enough that we compute a location for the blast and post it to a separate explosions listing.