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Well 27F  2 SOW 019 Observation well 27F2 SOW 019, located in Christiansburg, Va., is sensitive to teleseismic waves generated by large earthquakes (usually greater than magnitude 6.0) that occur around the world. This well is 450 feet deep, finished in carbonate rocks of the Elbrook Formation, and water enters the well via fractures or cracks in the rock. Compression and expansion of these fractures by seismic waves cause the water to be drawn in and out of the well, similar to the way bellows work.  As ground water moves in and out of the well, the water level in the well rapidly rises and falls.  This water-level oscillation is recorded at 5-minute intervals by a pressure transducer and data logger maintained by the Virginia Department of Environmental Quality.  Every hour, these data are transmitted via satellite to a computer located at the U.S. Geological Survey Virginia Water Science Center in Richmond, Va.  Below is a list of recent earthquakes that caused a water-level response in this well.  Click on the location link in the table below to see a hydrograph of the response.
New Groundwater-Level Response to the Mineral, Virginia Earthquake, August 23, 2011
New Video of Groundwater Response to M7.4 Guatemala Earthquake Nov. 7, 2012

Locations of Earthquakes

World map/quake locations.

 

Magnitude Location Date-Time
(UTC)
Date-Time
(Local)
Depth of
epicenter
(miles)
Distance
from
epicenter
to well
(miles)
Water-Level Oscillation
Rise
(feet below
land surface)
Fall
(feet below
land surface)
Total
(feet)
Period
(hours)
6.6 LAMJUNG, NEPAL 04/25/2015 06:45:21 04/25/2015 02:45:21 9.1 7,837 2.10 2.68 0.58 1.67
7.8 LAMJUNG, NEPAL 04/25/2015 06:11:26 04/25/2015 02:11:26 9.3 7,838 2.10 2.68 0.58 2.25
6.2 BELLA BELLA, CANADA 04/24/2015 13:56:16 04/24/2015 09:56:16 6.2 2,621 2.50 2.62 0.12 0.17
7.5 OKOPO, PAPUA NEW GUINEA 03/29/2015 23:48:31 03/29/2015 18:48:31 24.9 8,427 2.56 2.73 0.17 1.67
6.7 MIYAKO, JAPAN 02/16/2015 23:06:28 02/16/2015 18:06:28 14.3 6,464 4.42 4.46 0.04 0.25
7.1 NORTHERN MID-ATLANTIC RIDGE 02/13/2015 18:59:12 02/13/2015 13:59:12 10.2 2,553 4.32 4.56 0.24 0.33
6.5 PUNTA DE BURICA, PANAMA 01/07/2015 05:07:07 01/07/2015 00:07:07 5.0 2,154 3.50 3.52 0.02 0.08
6.6 PUNTA DE BURICA, PANAMA 12/08/2014 08:54:52 12/08/2014 03:54:52 12.4 2,012 2.94 3.13 0.19 0.25
6.8 PANGUNA, PAPUA NEW GUINEA 12/07/2014 01:22:00 12/06/2014 20:22:00 6.2 8,408 3.04 3.10 0.06 0.42
7.1 KOTA TERNATE, INDONESIA 11/15/2014 02:31:40 11/14/2014 21:31:40 21.7 9,238 4.60 4.64 0.04 0.17
7.3 JIQUILILLO, NICARAGUA 10/14/2014 03:51:35 10/13/2014 23:51:35 24.9 1,755 3.87 4.23 0.36 0.75
6.6 SOUTHERN EAST PACIFIC RISE 10/09/2014 02:32:05 10/08/2014 22:32:05 6.2 5,154 4.26 4.36 0.10 0.25
7.1 SOUTHERN EAST PACIFIC RISE 10/09/2014 02:14:32 10/08/2014 22:14:32 9.6 5,151 4.26 4.36 0.10 0.25
6.9 TAMBO, PERU 08/24/2014 23:21:45 08/24/2014 19:21:45 62.8 3,585 4.43 4.50 0.07 0.33
6.0 AMERICAN CANYON, CALIFORNIA 08/24/2014 10:20:44 08/24/2014 06:20:44 7.0 2,277 4.41 4.48 0.07 0.08
6.5 NAMIE, JAPAN 07/11/2014 19:21:59 07/11/2014 15:21:59 6.5 6,641 5.04 5.08 0.04 0.33
6.9 PUERTO MADERO, MEXICO 07/07/2014 11:23:55 07/07/2014 07:23:55 37.3 1,709 5.04 5.25 0.21 0.42
6.6 BULDIR ISLAND, ALASKA 06/24/2014 03:15:41 06/23/2014 23:15:41 21.7 4,734 4.63 4.65 0.02 0.08
7.9 LITTLE SITKIN ISLAND, ALASKA 06/23/2014 20:53:09 06/23/2014 16:53:09 66.8 4,678 4.42 4.60 0.18 1.92
6.2 RAOUL ISLAND, NEW ZEALAND 06/23/2014 20:06:19 06/23/2014 16:06:19 12.4 7,785 4.48 4.54 0.06 0.50
6.3 RAOUL ISLAND, NEW ZEALAND 06/23/2014 19:21:48 06/23/2014 15:21:48 12.4 7,793 4.48 4.54 0.06 0.50
6.9 RAOUL ISLAND, NEW ZEALAND 06/23/2014 19:19:16 06/23/2014 15:19:16 12.4 7,798 4.48 4.54 0.06 0.50
6.8 PUNTA DE BURICA, PANAMA 05/13/2014 06:35:24 05/13/2014 02:35:24 6.2 2,060 3.58 3.72 0.14 0.25
6.4 TECPAN DE GALEANA, MEXICO 05/08/2014 17:00:17 05/08/2014 13:00:17 14.9 1,835 3.43 3.49 0.06 0.17
6.6 PORT HARDY, CANADA 04/24/2014 03:10:12 04/23/2014 23:10:12 7.1 2,473 2.87 3.37 0.50 0.50
7.5 PANGUNA, PAPUA NEW GUINEA 04/19/2014 13:27:59 04/19/2014 09:27:59 19.2 8,390 2.79 3.22 0.43 1.42
7.2 TECPAN DE GALEANA, MEXICO 04/18/2014 14:27:26 04/18/2014 10:27:26 14.9 1,832 3.02 3.22 0.20 1.75
7.4 KIRAKIRA, SOLOMON ISLANDS 04/13/2014 12:36:18 04/13/2014 08:36:18 21.7 8,206 3.00 3.25 0.25 1.58
7.6 KIRAKIRA, SOLOMON ISLANDS 04/12/2014 20:14:39 04/12/2014 16:14:39 18.2 8,193 2.63 3.01 0.38 1.92
7.1 PANGUNA, PAPUA NEW GUINEA 04/11/2014 07:07:21 04/11/2014 03:07:21 31.1 8,379 2.81 2.87 0.06 0.42
6.1 VALLE SAN FRANCISCO, NICARAGUA 04/10/2014 23:27:46 04/10/2014 19:27:46 8.1 1,734 2.87 2.93 0.06 0.25
7.7 IQUIQUE, CHILE 04/03/2014 02:43:14 04/02/2014 22:43:14 19.3 4,018 2.96 3.65 0.69 1.33
6.5 IQUIQUE, CHILE 04/03/2014 01:58:31 04/02/2014 21:58:31 14.2 40 2.99 3.06 0.07 0.17
6.9 IQUIQUE, CHILE 04/01/2014 23:57:57 04/01/2014 19:57:57 12.6 3,971 2.55 3.10 0.55 3.08
8.2 IQUIQUE, CHILE 04/01/2014 23:46:46 04/01/2014 19:46:46 12.5 3,955 2.55 3.10 0.55 3.08
6.2 IQUIQUE, CHILE (BETA) 03/17/2014 05:11:34 03/17/2014 01:11:34 13.0 3,980 2.36 2.40 0.04 0.08
6.7 IQUIQUE, CHILE (BETA) 03/16/2014 21:16:29 03/16/2014 17:16:29 12.4 3,981 2.17 2.31 0.14 0.75
6.9 FERNDALE, CALIFORNIA 03/10/2014 05:18:13 03/10/2014 01:18:13 10.3 2,394 1.94 2.01 0.07 0.42
6.5 BATHSHEBA, BARBADOS 02/18/2014 09:27:13 02/18/2014 04:27:13 10.5 2,036 2.74 2.80 0.06 0.08
6.9 HOTAN, CHINA 02/12/2014 09:19:48 02/12/2014 04:19:48 6.2 7,287 2.66 2.78 0.12 0.83
6.4 HATILLO, PUERTO RICO 01/13/2014 04:01:04 01/12/2014 23:01:04 17.4 1,496 2.28 2.36 0.08 0.33
7.0 SOUTH ATLANTIC OCEAN 11/25/2013 06:27:33 11/25/2013 01:27:33 6.2 6,450 4.99 5.10 0.11 1.08
7.7 SCOTIA SEA 11/17/2013 09:04:05 11/17/2013 04:04:05 6.2 6,982 4.63 4.83 0.20 2.58
7.1 OFF THE EAST COAST OF HONSHU, JAPAN 10/25/2013 17:10:18 10/25/2013 13:10:18 16.2 6,565 4.58 4.69 0.11 1.00
6.5 ETCHOROPO, MEXICO 10/19/2013 17:54:56 10/19/2013 13:54:56 5.0 1,895 4.26 4.32 0.06 0.42
7.1 CATIGBIAN, PHILIPPINES 10/15/2013 00:12:32 10/14/2013 20:12:32 12.4 8,832 4.16 4.24 0.08 0.33
6.8 AWARAN, PAKISTAN 09/28/2013 07:34:07 09/28/2013 03:34:07 9.2 7,484 4.46 4.59 0.13 0.33
7.0 ACARI, PERU 09/25/2013 16:42:42 09/25/2013 12:42:42 24.9 3,667 4.30 4.63 0.33 0.58
7.7 AWARAN, PAKISTAN 09/24/2013 11:29:48 09/24/2013 07:29:48 12.4 7,498 3.66 4.79 1.13 2.00
6.6 CIUDAD TECUN UMAN, GUATEMALA 09/07/2013 00:13:29 09/06/2013 20:13:29 41.6 1,707 4.04 4.08 0.04 0.08
6.0 SARDINAL, COSTA RICA 09/05/2013 12:29:15 09/05/2013 08:29:15 11.2 2,424 3.97 4.00 0.03 0.17
6.5 ATKA, ALASKA 09/04/2013 02:32:33 09/03/2013 22:32:33 24.8 4,445 3.91 3.95 0.04 0.25
6.0 BELLA BELLA, CANADA 09/03/2013 20:19:06 09/03/2013 16:19:06 0.6 2,607 3.68 3.73 0.05 0.17
7.0 ADAK, ALASKA 08/30/2013 16:25:02 08/30/2013 12:25:02 20.8 4,467 3.73 4.04 0.31 0.58
6.2 SAN MARCOS, MEXICO 08/21/2013 12:38:30 08/21/2013 08:38:30 12.4 1,809 3.51 3.54 0.03 0.42
6.5 LENHEIM, NEW ZEALAND 08/16/2013 02:31:07 08/15/2013 22:31:07 6.2 8,570 3.52 3.54 0.02 0.08
6.6 MUTIS, COLOMBIA 08/13/2013 15:43:13 08/13/2013 11:43:13 6.2 2,164 3.15 3.28 0.13 6.33
7.3 BRISTOL ISLAND, SOUTH SANDWICH ISLANDS 07/15/2013 14:03:43 07/15/2013 10:03:43 19.3 7,433 1.84 1.89 0.05 0.33
6.5 MASACHAPA, NICARAGUA 06/15/2013 17:34:29 06/15/2013 13:34:29 22.2 1,796 2.47 2.55 0.08 0.25
8.3 SEA OF OKHOTSK 05/24/2013 05:44:49 05/24/2013 01:44:49 378.4 5,344 2.27 2.64 0.37 1.92
6.6 LINQIONG, CHINA 04/20/2013 00:02:47 04/19/2013 20:02:47 7.6 7,787 2.26 2.32 0.06 0.17
7.0 ENAROTALI, INDONESIA 04/06/2013 04:42:36 04/06/2013 00:42:36 42.3 9,058 2.26 2.30 0.04 0.42
6.9 OZERNOVSKIY, RUSSIA 02/28/2013 14:05:51 02/28/2013 09:05:51 32.6 5,431 2.64 2.69 0.05 0.42
6.6 DRUZHINA, RUSSIA 02/14/2013 13:13:52 02/14/2013 08:13:52 6.2 4,875 2.19 2.28 0.09 0.33
6.9 YACUANQUER, COLOMBIA 02/09/2013 14:16:07 02/09/2013 09:16:07 90.1 2,484 2.11 2.17 0.06 0.17
7.1 LATA, SOLOMON ISLANDS 02/08/2013 15:26:38 02/08/2013 10:26:38 13.0 7,968 1.91 1.96 0.05 0.58
6.8 LATA, SOLOMON ISLANDS 02/08/2013 11:12:13 02/08/2013 06:12:13 11.2 7,974 1.86 1.93 0.07 0.50
6.7 LATA, SOLOMON ISLANDS 02/07/2013 18:59:16 02/07/2013 13:59:16 6.2 7,991 1.90 1.98 0.08 0.67
6.6 SANTA CRUZ ISLANDS 02/06/2013 01:54:15 02/05/2013 20:54:15 6.3 7,967 1.90 2.10 0.20 2.17
6.4 SANTA CRUZ ISLANDS REGION 02/06/2013 01:23:19 02/05/2013 20:23:19 6.3 8,041 1.90 2.10 0.20 2.75
8.0 SANTA CRUZ ISLANDS 02/06/2013 01:12:27 02/05/2013 20:12:27 17.8 8,009 1.90 2.10 0.20 2.75
6.3 LATA, SOLOMON ISLANDS 02/06/2013 00:07:22 02/05/2013 19:07:22 6.2 8,010 1.90 2.10 0.20 2.75
6.9 OBIHIRO, JAPAN 02/02/2013 14:17:34 02/02/2013 09:17:34 64.1 6,288 1.73 1.75 0.02 0.17
6.3 AVALON, CALIFORNIA 12/14/2012 10:36:02 12/14/2012 05:36:02 7.0 2,262 5.91 5.94 0.03 0.08
6.2 OFUNATO, JAPAN 12/07/2012 08:31:14 12/07/2012 03:31:14 18.1 6,548 5.80 6.03 0.23 1.42
7.3 KAMAISHI, JAPAN 12/07/2012 08:18:24 12/07/2012 03:18:24 22.4 6,541 5.80 6.03 0.23 1.42
6.4 CAPE YAKATAGA, ALASKA 11/12/2012 20:42:17 11/12/2012 15:42:17 7.5 3,116 5.57 5.61 0.04 0.08
6.5 CHAMPERICO, GUATEMALA 11/11/2012 22:15:00 11/11/2012 17:15:00 16.8 1,739 5.75 5.77 0.02 0.42
6.8 SHWEBO, MYANMAR 11/11/2012 01:12:38 11/10/2012 20:12:38 6.1 8,286 5.91 5.97 0.06 0.25
7.4 CHAMPERICO, GUATEMALA 11/07/2012 16:35:50 11/07/2012 11:35:50 25.8 1,738 nd nd nd nd
6.2 MASSET, CANADA 10/30/2012 02:49:02 10/29/2012 22:49:02 6.0 2,674 5.77 5.82 0.05 0.08
6.3 MASSET, CANADA 10/28/2012 18:54:21 10/28/2012 14:54:21 5.1 2,709 5.80 5.84 0.04 0.17
7.7 MASSET, CANADA 10/28/2012 03:04:10 10/27/2012 23:04:10 10.9 2,676 5.06 6.25 1.19 1.42
7.3 SAN AGUSTIN, COLOMBIA 09/30/2012 16:31:35 09/30/2012 12:31:35 104.6 2,437 5.69 5.79 0.10 0.25
6.4 TANAGA VOLCANO, ALASKA 09/26/2012 23:39:54 09/26/2012 19:39:54 6.2 4,576 5.74 5.77 0.03 0.67
6.2 LA PAZ, MEXICO 09/25/2012 23:45:26 09/25/2012 19:45:26 6.3 1,946 5.69 5.72 0.03 0.25
7.6 HOJANCHA, COSTA RICA 09/05/2012 14:42:07 09/05/2012 10:42:07 25.0 1,893 4.96 6.07 1.11 1.75
7.6 SULANGAN, PHILIPPINES 08/31/2012 12:47:34 08/31/2012 08:47:34 21.7 8,693 5.76 6.08 0.32 1.75
7.3 PUERTO EL TRIUNFO, EL SALVADOR 08/27/2012 04:37:20 08/27/2012 00:37:20 12.6 1,783 5.15 5.68 0.53 1.58
7.7 PORONAYSK, RUSSIA 08/14/2012 02:59:42 08/13/2012 22:59:42 388.9 5,834 5.45 5.53 0.08 0.42
6.3 AHAR, IRAN 08/11/2012 12:34:35 08/11/2012 08:34:35 6.1 6,247 5.40 5.43 0.03 0.25
6.4 AHAR, IRAN 08/11/2012 12:23:17 08/11/2012 08:23:17 6.2 6,252 5.40 5.43 0.03 0.25
6.2 NIKOLSKI, ALASKA 08/10/2012 18:37:42 08/10/2012 14:37:42 8.0 4,131 5.24 5.30 0.06 0.33
6.9 GULF OF CALIFORNIA 04/12/2012 07:15:48 04/12/2012 03:15:48 6.4 1,974 3.41 3.72 0.31 1.08
6.2 GULF OF CALIFORNIA 04/12/2012 07:06:01 04/12/2012 03:06:01 6.3 1,969 3.41 3.72 0.31 1.08
6.5 MICHOACAN, MEXICO 04/11/2012 22:55:10 04/11/2012 18:55:10 12.4 1,876 3.56 3.65 0.09 0.67
8.2 OFF THE WEST COAST OF NORTHERN SUMATRA 04/11/2012 10:43:09 04/11/2012 06:43:09 10.2 9,783 3.17 4.26 1.09 2.42
8.6 OFF THE WEST COAST OF NORTHERN SUMATRA 04/11/2012 08:38:37 04/11/2012 04:38:37 14.2 9,685 2.43 3.99 1.56 2.08
7.1 MAULE, CHILE 03/25/2012 22:37:06 03/25/2012 18:37:06 21.6 5,006 2.50 2.57 0.07 0.83
7.4 OAXACA, MEXICO 03/20/2012 18:02:48 03/20/2012 14:02:48 12.4 1,778 2.81 3.06 0.25 2.42
6.7 SOUTHWESTERN SIBERIA, RUSSIA 02/26/2012 06:17:19 02/26/2012 01:17:19 7.3 6,308 2.79 2.84 0.05 2.92
6.7 NEGROS - CEBU REGION, PHILIPPINES 02/06/2012 03:49:16 02/05/2012 22:49:16 6.8 8,847 3.23 3.27 0.04 0.25
7.1 VANUATU 02/02/2012 13:34:40 02/02/2012 08:34:40 14.4 8,174 3.17 3.25 0.08 8.50
7.2 OFF THE WEST COAST OF NORTHERN SUMATRA 01/10/2012 18:36:59 01/10/2012 13:36:59 12.7 9,677 3.20 3.27 0.07 1.25
6.6 SOUTHWESTERN SIBERIA, RUSSIA 12/27/2011 15:21:56 12/27/2011 10:21:56 9.3 6,301 2.59 2.65 0.06 0.83
7.1 EASTERN NEW GUINEA REG, PAPUA NEW GUINEA 12/14/2011 05:04:57 12/14/2011 00:04:57 75.3 8,850 2.91 2.93 0.02 0.25
6.9 NEAR THE COAST OF CENTRAL PERU 10/28/2011 18:54:33 10/28/2011 14:54:33 14.9 3,564 5.25 5.33 0.08 0.75
7.2 EASTERN TURKEY 10/23/2011 10:41:21 10/23/2011 06:41:21 12.4 6,116 5.15 5.28 0.13 1.50
7.4 KERMADEC ISLANDS REGION 10/21/2011 17:57:16 10/21/2011 13:57:16 20.4 7,682 4.95 5.07 0.12 1.42
6.7 NEAR THE EAST COAST OF HONSHU, JAPAN 09/16/2011 19:26:41 09/16/2011 15:26:41 23.9 6,441 5.09 5.14 0.05 0.08
6.4 VANCOUVER ISLAND, CANADA REGION 09/09/2011 19:41:34 09/09/2011 15:41:34 14.3 2,451 4.35 4.37 0.02 0.67
6.8 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 09/02/2011 10:55:54 09/02/2011 06:55:54 22.1 4,309 5.56 5.81 0.25 1.92
5.8 MINERAL, VIRGINIA 08/23/2011 17:51:04 08/23/2011 13:51:04 3.7 149 na 5.29 0.51 7.92
7.0 VANUATU 08/20/2011 18:19:24 08/20/2011 14:19:24 17.7 8,138 4.65 4.71 0.06 1.00
7.1 VANUATU 08/20/2011 16:55:02 08/20/2011 12:55:02 25.2 8,141 4.67 4.70 0.03 0.83
7.0 OFF THE EAST COAST OF HONSHU, JAPAN 07/10/2011 00:57:12 07/09/2011 20:57:12 11.2 6,557 3.44 3.56 0.12 1.00
7.6 KERMADEC ISLANDS REGION 07/06/2011 19:03:16 07/06/2011 15:03:16 12.4 7,694 3.31 3.64 0.33 1.75
7.2 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 06/24/2011 03:09:40 06/23/2011 23:09:40 38.9 4,914 2.63 3.00 0.37 0.83
6.8 LOYALTY ISLANDS 05/10/2011 08:55:09 05/10/2011 04:55:09 9.3 8,203 2.75 2.85 0.10 0.42
7.1 NEAR THE EAST COAST OF HONSHU, JAPAN 04/07/2011 14:32:41 04/07/2011 10:32:41 30.4 6,593 2.49 2.56 0.07 0.67
6.8 MYANMAR 03/24/2011 13:55:12 03/24/2011 09:55:12 6.2 8,452 2.31 2.37 0.06 1.00
6.8 OFF THE EAST COAST OF HONSHU, JAPAN 03/12/2011 01:47:16 03/11/2011 20:47:16 15.4 6,601 2.08 2.13 0.05 0.17
7.1 OFF THE EAST COAST OF HONSHU, JAPAN 03/11/2011 06:25:50 03/11/2011 01:25:50 12.2 6,514 0.01 2.71 2.70 3.42
6.8 NEAR THE EAST COAST OF HONSHU, JAPAN 03/11/2011 06:15:40 03/11/2011 01:15:40 21.7 6,727 0.01 2.71 2.70 3.58
9.0 NEAR THE EAST COAST OF HONSHU, JAPAN 03/11/2011 05:46:23 03/11/2011 00:46:23 15.2 6,568 0.01 2.71 2.70 4.00
7.2 NEAR THE EAST COAST OF HONSHU, JAPAN 03/09/2011 02:45:18 03/08/2011 21:45:18 8.8 6,544 2.54 2.89 0.35 0.83
5.9 NEAR THE EAST COAST OF KAMCHATKA, RUSSIA 02/20/2011 21:43:20 02/20/2011 16:43:20 6.0 5,049 5.13 5.18 0.05 0.25
6.6 OFFSHORE MAULE, CHILE 02/14/2011 03:40:10 02/13/2011 22:40:10 15.8 5,017 5.10 5.16 0.06 0.50
6.8 OFFSHORE BIO-BIO, CHILE 02/11/2011 20:05:30 02/11/2011 15:05:30 11.2 5,078 5.08 5.13 0.05 0.83
7.2 SOUTHWESTERN PAKISTAN 01/18/2011 20:23:26 01/18/2011 15:23:26 52.2 7,341 4.67 4.80 0.13 0.42
7.0 LOYALTY ISLANDS 01/13/2011 16:16:41 01/13/2011 11:16:41 5.6 8,206 4.89 4.94 0.05 0.58
7.1 ARAUCANIA, CHILE 01/02/2011 20:20:18 01/02/2011 15:20:18 15.6 5,214 3.86 3.92 0.06 1.25
7.3 VANUATU REGION 12/25/2010 13:16:37 12/25/2010 08:16:37 7.6 8,206 4.91 5.02 0.11 1.92
7.4 BONIN ISLANDS, JAPAN REGION 12/21/2010 17:19:40 12/21/2010 12:19:40 8.7 7,179 5.04 5.27 0.23 1.50
7.7 KEPULAUAN MENTAWAI REGION, INDONESIA 10/25/2010 14:42:22 10/25/2010 10:42:22 12.8 10,114 5.30 5.44 0.14 1.08
6.7 GULF OF CALIFORNIA 10/21/2010 17:53:14 10/21/2010 13:53:14 6.2 1,893 5.10 5.34 0.24 1.08
6.1 ANDREANOF ISLANDS, ALEUTIAN IS. 10/08/2010 03:49:00 10/07/2010 23:49:00 21.7 4,467 5.36 5.42 0.06 0.58
6.4 ANDREANOF ISLANDS, ALEUTIAN IS. 10/08/2010 03:26:00 10/07/2010 23:26:00 12.4 4,476 5.36 5.42 0.06 0.58
7.0 SOUTH ISLAND OF NEW ZEALAND 09/03/2010 16:35:46 09/03/2010 12:35:46 3.1 8,705 5.11 5.26 0.15 0.17
6.3 ANDREANOF ISLANDS, ALEUTIAN IS., ALASKA 09/03/2010 11:16:08 09/03/2010 07:16:08 31.6 4,486 5.28 5.32 0.04 0.25
6.9 MARIANA ISLANDS REGION 08/13/2010 21:19:33 08/13/2010 17:19:33 6.2 8,070 5.15 5.26 0.11 0.25
7.1 ECUADOR 08/12/2010 11:54:16 08/12/2010 07:54:16 131.1 2,649 5.07 5.22 0.15 0.25
7.3 VANUATU 08/10/2010 05:23:46 08/10/2010 01:23:46 21.7 8,116 5.21 5.29 0.08 0.67
6.2 OFF EAST COAST OF KAMCHATKA 07/30/2010 03:56:00 07/29/2010 23:56:00 13.0 5,275 5.09 5.13 0.04 0.17
7.4 MORO GULF, MINDANAO, PHILIPPINES 07/23/2010 23:15:08 07/23/2010 19:15:08 383.2 9,048 4.96 5.03 0.07 0.92
7.6 MORO GULF, MINDANAO, PHILIPPINES 07/23/2010 22:51:12 07/23/2010 18:51:12 362.8 9,058 4.96 5.03 0.07 0.92
7.3 MORO GULF, MINDANAO, PHILIPPINES 07/23/2010 22:08:11 07/23/2010 18:08:11 380.4 9,045 4.96 5.03 0.07 0.92
7.3 NEW BRITAIN REGION, PAPUA NEW GUINEA 07/18/2010 13:34:59 07/18/2010 09:34:59 21.7 8,583 4.73 4.87 0.14 1.17
6.9 NEW BRITAIN REGION, PAPUA NEW GUINEA 07/18/2010 13:04:11 07/18/2010 09:04:11 26.1 8,593 4.79 4.82 0.03 0.17
6.6 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 07/18/2010 05:56:44 07/18/2010 01:56:44 6.2 4,218 4.73 4.96 0.23 0.67
6.5 BIO-BIO, CHILE 07/14/2010 08:32:22 07/14/2010 04:32:22 17.6 5,190 4.83 4.87 0.04 0.58
7.5 NICOBAR ISLANDS, INDIA REGION 06/12/2010 19:26:50 06/12/2010 15:26:50 21.7 9,304 3.97 4.19 0.22 1.08
6.1 COSTA RICA 06/01/2010 03:26:00 05/31/2010 23:26:00 18.0 1,927 3.43 3.46 0.03 0.08
7.1 VANUATU 05/27/2010 17:14:48 05/27/2010 13:14:48 22.4 8,052 3.29 3.36 0.07 0.42
6.4 SOUTHEAST OF RYUKYU ISLANDS 05/26/2010 08:53:00 05/26/2010 04:53:00 2.5 7,674 3.02 3.04 0.02 0.08
7.2 NORTHERN SUMATRA, INDONESIA 05/09/2010 05:59:42 05/09/2010 01:59:42 28.0 9,606 3.28 3.40 0.12 0.50
6.0 BERING SEA 04/30/2010 23:16:00 04/30/2010 19:16:00 9.3 4,266 2.76 2.80 0.04 0.58
6.9 SOUTHERN QINGHAI, CHINA 04/13/2010 23:49:38 04/13/2010 19:49:38 10.6 7,586 2.25 2.31 0.06 0.58
7.8 NORTHERN SUMATRA, INDONESIA 04/06/2010 22:15:02 04/06/2010 17:15:02 19.3 9,708 1.70 2.67 0.97 1.83
6.6 SOUTHERN CALIFORNIA 04/04/2010 22:41:12 04/04/2010 17:41:12 3.7 2,024 1.57 1.99 0.42 1.58
6.9 BAJA CALIFORNIA, MEXICO 04/04/2010 22:40:39 04/04/2010 17:40:39 19.9 2,003 1.57 1.99 0.42 1.58
6.7 LIBERTADOR O'HIGGINS, CHILE 03/11/2010 14:55:27 03/11/2010 09:55:27 11.2 4,944 1.47 1.61 0.14 0.83
6.9 LIBERTADOR O'HIGGINS, CHILE 03/11/2010 14:39:44 03/11/2010 09:39:44 6.8 4,942 1.47 1.61 0.14 0.83
6.5 SOUTHWEST OF SUMATRA, INDONESIA 03/05/2010 16:06:57 03/05/2010 11:06:57 13.7 10,151 1.67 1.73 0.06 0.25
6.9 OFF THE COAST OF BIO-BIO, CHILE 02/27/2010 08:01:24 02/27/2010 03:01:24 24.2 5,156 1.20 1.45 0.25 2.42
8.8 OFFSHORE MAULE, CHILE 02/27/2010 06:34:14 02/27/2010 01:34:14 21.7 5,045 0.99 3.43 2.44 3.75
7.0 RYUKYU ISLANDS, JAPAN 02/26/2010 20:31:27 02/26/2010 15:31:27 13.7 7,708 1.25 1.33 0.08 0.67
7.0 HAITI REGION 1/12/2010 21:53:10 1/12/2010 16:53:10 8.1 1,373 1.21 2.00 0.79 1.92
6.8 SOLOMON ISLANDS 1/5/2010 12:15:32 1/5/2010 07:15:32 11.6 8,350 1.40 1.43 0.03 0.25
6.7 EAST OF SOUTH SANDWICH ISLANDS 1/5/2010 04:55:39 1/4/2010 23:55:39 6.2 7,569 1.47 1.54 0.07 0.75
7.1 SOLOMON ISLANDS 1/3/2010 22:36:28 1/3/2010 17:36:28 15.5 8,351 1.27 1.33 0.06 0.92
6.8 TONGA 11/24/2009 12:47:14 11/24/2009 07:47:14 6.2 7,257 2.03 2.05 0.02 0.50
6.6 QUEEN CHARLOTTE ISLANDS REGION 11/17/2009 15:30:46 11/17/2009 10:30:46 7.2 2,651 1.97 2.09 0.12 0.75
6.5 OFFSHORE TARAPACA CHILE 11/13/2009 03:05:57 11/12/2009 22:05:57 17.4 3,943 1.85 1.87 0.02 0.17
6.8 RYUKYU ISLANDS, JAPAN 10/30/2009 07:03:39 10/30/2009 03:03:39 21.7 7,465 3.93 3.96 0.03 0.25
6.9 BANDA SEA 10/24/2009 14:40:44 10/24/2009 10:40:44 83.4 9,552 4.39 4.41 0.02 0.75
6.3 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 10/13/2009 20:21:54 10/13/2009 16:21:54 8.5 4,121 4.41 4.50 0.09 0.83
6.2 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 10/13/2009 05:37:21 10/13/2009 01:37:21 11.2 4,109 4.38 4.41 0.03 0.42
6.8 VANUATU 10/08/2009 08:28:48 10/08/2009 04:28:48 21.7 8,067 4.37 4.43 0.06 1.00
7.3 VANUATU 10/07/2009 23:13:49 10/07/2009 19:13:49 20.7 8,041 4.16 4.41 0.25 1.25
7.8 SANTA CRUZ ISLANDS 10/07/2009 22:18:26 10/07/2009 18:18:26 21.7 8,024 4.16 4.41 0.25 1.75
7.6 VANUATU 10/07/2009 22:03:15 10/07/2009 18:03:15 21.7 8,044 4.16 4.41 0.25 1.75
6.7 CELEBES SEA 10/07/2009 21:41:14 10/07/2009 17:41:14 362.1 9,236 4.19 4.34 0.15 0.17
6.6 SOUTHERN SUMATRA, INDONESIA 10/01/2009 01:52:29 09/30/2009 21:52:29 9.3 10,043 4.06 4.11 0.05 0.17
7.6 SOUTHERN SUMATRA, INDONESIA 09/30/2009 10:16:09 09/30/2009 06:16:09 49.7 9,929 3.90 4.04 0.14 1.08
8.0 SAMOA ISLANDS REGION 09/29/2009 17:48:10 09/29/2009 13:48:10 11.2 6,944 3.66 3.90 0.24 2.83
6.6 SOUTHWESTERN RYUKYU ISLANDS, JAPAN 08/17/2009 00:05:47 08/16/2009 20:05:47 4.2 7,980 3.82 3.89 0.07 0.67
6.6 KEPULAUAN MENTAWAI REGION, INDONESIA 08/16/2009 07:38:21 08/16/2009 03:38:21 12.4 9,977 3.79 3.85 0.06 0.42
6.4 NEAR THE SOUTH COAST OF HONSHU, JAPAN 08/10/2009 20:07:07 08/10/2009 16:07:07 16.2 6,895 3.33 3.72 0.39 1.33
7.6 ANDAMAN ISLANDS, INDIA REGION 08/10/2009 19:55:39 08/10/2009 15:55:39 20.6 8,886 3.33 3.72 0.39 1.33
6.6 SANTA CRUZ ISLANDS 08/10/2009 04:06:31 08/10/2009 00:06:31 21.7 7,992 3.56 3.59 0.03 0.08
6.9 GULF OF CALIFORNIA 08/03/2009 17:59:56 08/03/2009 13:59:56 6.2 1,951 3.04 3.13 0.09 1.33
7.6 OFF WEST COAST OF THE SOUTH ISLAND, N.Z. 07/15/2009 09:22:29 07/15/2009 05:22:29 7.5 9,012 2.81 2.92 0.11 2.50
6.4 CRETE, GREECE 07/01/2009 09:30:10 07/01/2009 05:30:10 11.8 5,599 2.15 2.17 0.02 0.08
7.3 OFFSHORE HONDURAS 05/28/2009 08:24:45 05/28/2009 04:24:45 6.2 1,448 1.31 1.69 0.38 1.42
6.9 KURIL ISLANDS 04/07/2009 04:23:34 04/07/2009 00:23:34 21.1 5,860 3.30 3.36 0.06 0.58
7.9 TONGA  REGION 03/19/2009 18:17:40 03/19/2009 14:17:40 21.1 7,381 3.08 3.27 0.19 1.92
6.9 KERMADEC ISLANDS REGION 02/18/2009 21:53:45 02/18/2009 16:53:45 15.5 7,637 5.71 5.77 0.06 0.67
7.3 KEPULAUAN TALAUD, INDONESIA 02/11/2009 17:34:50 02/11/2009 12:34:50 12.4 9,125 5.83 5.88 0.05 0.50
7.3 NEAR THE COAST OF PAPUA, INDONESIA 01/03/2009 22:33:42 01/03/2009 17:33:42 21.7 9,134 6.35 6.43 0.08 1.33
7.6 NEAR THE COAST OF PAPUA, INDONESIA 01/03/2009 19:43:54 01/03/2009 14:43:54 21.7 9,143 6.36 6.57 0.21 1.33
6.2 PANAMA-COSTA RICA BORDER REGION 11/19/2008 06:11:02 11/19/2008 01:11:02 30.0 1,991 6.83 6.89 0.06 0.17
7.5 MINAHASA, SULAWESI, INDONESIA 11/16/2008 17:02:32 11/16/2008 12:02:32 16.2 9,421 6.81 6.86 0.05 1.50
6.5 NORTHERN QINGHAI, CHINA 11/10/2008 01:22:01 11/09/2008 20:22:01 6.2 7,281 7.03 7.06 0.03 0.17
6.1 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 11/02/2008 13:48:44 11/02/2008 08:48:44 31.9 4,429 6.86 6.89 0.03 0.17
6.6 OFFSHORE CHIAPAS, MEXICO 10/16/2008 19:41:26 10/16/2008 15:41:26 14.9 1,729 6.73 6.79 0.06 0.33
6.1 VIRGIN ISLANDS REGION 10/11/2008 10:40:16 10/11/2008 06:40:16 16.0 1,550 6.82 6.88 0.06 0.17
6.6 KYRGYZSTAN 10/05/2008 15:52:49 10/05/2008 11:52:49 17.1 6,908 6.79 6.81 0.02 0.08
6.9 HOKKAIDO, JAPAN REGION 09/11/2008 00:20:52 09/10/2008 20:20:52 21.7 6,321 6.62 6.67 0.05 0.25
6.6 HALMAHERA, INDONESIA 09/11/2008 00:00:02 09/10/2008 20:00:02 57.8 9,211 6.62 6.68 0.06 0.33
6.6 CENTRAL MID-ATLANTIC RIDGE 09/10/2008 13:08:14 09/10/2008 09:08:14 6.2 3,287 6.69 6.73 0.04 0.25
6.9 VANUATU 09/08/2008 18:52:08 09/08/2008 14:52:08 75.7 8,019 6.57 6.59 0.02 0.17
5.9 VANCOUVER ISLAND, CANADA REGION 08/28/2008 12:37:35 08/28/2008 08:37:35 6.2 2,569 6.36 6.38 0.02 0.08
7.0 OFF THE EAST COAST OF HONSHU, JAPAN 07/19/2008 02:39:30 07/18/2008 22:39:30 16.8 6,616 6.17 6.28 0.11 0.67
7.7 SEA OF OKHOTSK 07/05/2008 02:12:04 07/04/2008 22:12:04 393.5 5,407 6.05 6.12 0.07 0.42
6.7 EAST OF THE SOUTH SANDWICH ISLANDS 06/30/2008 06:17:43 06/30/2008 02:17:43 6.2 7,380 5.89 5.91 0.02 0.08
6.6 ANDAMAN ISLANDS, INDIA REGION 06/27/2008 11:40:16 06/27/2008 07:40:16 21.7 9,080 6.06 6.11 0.05 0.17
6.8 EASTERN HONSHU, JAPAN 06/13/2008 23:43:46 06/13/2008 19:43:46 6.2 6,572 5.93 6.05 0.12 1.00
6.3 ICELAND REGION 05/29/2008 15:46:00 05/29/2008 11:46:00 6.2 3,040 5.26 5.31 0.05 0.08
6.4 CENTRAL MID-ATLANTIC RIDGE 05/23/2008 19:35:35 05/23/2008 15:35:35 6.2 3,519 5.26 5.31 0.05 0.25
6.0 EASTERN SICHUAN, CHINA 05/12/2008 06:43:14 05/12/2008 02:43:14 6.2 7,720 4.12 5.31 1.19 4.75
7.9 EASTERN SICHUAN, CHINA 05/12/2008 06:28:00 05/12/2008 02:28:00 6.2 7,730 4.12 5.31 1.19 5.00
6.8 NEAR THE EAST COAST OF HONSHU, JAPAN 05/07/2008 16:45:20 05/07/2008 12:45:20 21.7 6,722 4.82 4.88 0.06 0.83
6.2 NEAR THE EAST COAST OF HONSHU, JAPAN 05/07/2008 16:02:02 05/07/2008 12:02:02 12.2 6,716 4.83 4.85 0.02 0.08
6.6 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 05/02/2008 01:33:36 05/01/2008 21:33:36 8.7 4,540 4.13 4.23 0.10 0.75
6.6 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 04/16/2008 05:54:19 04/16/2008 01:54:19 8.1 4,599 5.19 5.26 0.07 0.58
6.4 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 04/15/2008 22:59:54 04/15/2008 18:59:54 6.2 4,602 5.22 5.35 0.13 0.25
6.1 OFFSHORE GUATEMALA 04/15/2008 03:03:10 04/14/2008 23:03:10 49.4 1,734 5.21 5.23 0.02 0.08
7.1 MACQUARIE ISLAND REGION 04/12/2008 00:30:11 04/11/2008 20:30:11 6.2 9,453 4.69 4.77 0.08 1.17
6.0 LOYALTY ISLANDS 04/09/2008 14:47:51 04/09/2008 10:47:51 21.7 8,162 4.60 4.63 0.03 0.08
7.3 LOYALTY ISLANDS 04/09/2008 12:46:13 04/09/2008 08:46:13 21.7 8,164 4.50 4.62 0.12 1.00
6.3 LOYALTY ISLANDS 04/09/2008 11:23:40 04/09/2008 07:23:40 21.7 8,165 4.50 4.52 0.02 0.08
6.4 LOYALTY ISLANDS 04/09/2008 11:13:21 04/09/2008 07:13:21 21.7 8,172 4.50 4.52 0.02 0.08
6.3 SIMEULUE, INDONESIA 03/29/2008 17:30:51 03/29/2008 13:30:51 20.1 9,662 5.65 5.69 0.04 0.25
7.2 XINJIANG-XIZANG BORDER REGION 03/20/2008 22:33:00 03/20/2008 18:33:00 14.2 7,303 5.01 5.23 0.22 0.75
6.9 PHILLIPINE ISLANDS REGION 03/03/2008 14:11:13 03/03/2008 09:11:13 11.5 8,567 5.85 5.87 0.02 0.08
6.6 KURIL ISLANDS 03/03/2008 09:31:06 03/03/2008 04:31:06 21.7 5,789 5.75 5.83 0.08 0.33
6.6 KEPULAUAN MENTAWAI REGION, INDONESIA 02/25/2008 21:02:20 02/25/2008 16:02:20 24.3 10,027 5.50 5.57 0.07 0.33
7.0 KEPULAUAN MENTAWAI REGION, INDONESIA 02/25/2008 08:36:35 02/25/2008 03:36:35 21.7 10,036 5.27 5.65 0.38 0.50
6.8 SOUTH SANDWICH ISLANDS REGION 02/23/2008 15:57:24 02/23/2008 10:57:24 21.7 7,284 5.56 5.58 0.02 0.42
6.0 NEVADA 02/21/2008 14:16:02 02/21/2008 09:16:02 4.2 1,858 5.53 5.56 0.03 0.08
6.1 SVALBARD REGION 02/21/2008 02:46:18 02/20/2008 21:46:18 6.2 3,869 5.58 5.61 0.03 0.08
4.7 SIMEULUE, INDONESIA 02/20/2008 09:32:05 02/20/2008 04:32:05 14.0 9,680 5.26 5.34 0.08 0.67
6.1 SIMEULUE, INDONESIA 02/20/2008 09:05:08 02/20/2008 04:32:08 21.7 9,685 5.26 5.35 0.09 0.75
5.4 SIMEULUE, INDONESIA 02/20/2008 08:28:20 02/20/2008 03:28:20 21.7 9,689 5.26 5.35 0.09 1.17
7.4 SIMEULUE, INDONESIA 02/20/2008 08:08:32 02/20/2008 03:08:32 21.7 9,675 5.26 5.35 0.09 1.67
6.4 OAXACA, MEXICO 02/12/2008 12:50:20 02/12/2008 07:50:20 61.9 1,656 5.03 5.07 0.03 0.08
6.8 NORTHERN MID-ATLANTIC RIDGE 02/08/2008 09:38:14 02/08/2008 04:38:14 6.2 3,009 4.34 4.53 0.19 0.75
6.3 OFF THE COAST OF OREGON 01/10/2008 01:37:18 01/09/2008 20:37:18 6.2 2,478 5.71 5.75 0.04 0.08
6.1 QUEEN CHARLOTTE ISLANDS REGION 01/09/2008 14:40:01 01/09/2008 14:40:01 6.2 2,640 5.69 5.71 0.03 0.08
6.5 QUEEN CHARLOTTE ISLANDS REGION 01/05/2008 11:44:48 01/05/2008 6:44:48 6.2 2,613 5.55 5.59 0.04 0.75
6.5 QUEEN CHARLOTTE ISLANDS REGION 01/05/2008 11:01:05 01/05/2008 06:01:05 6.2 2,620 5.49 5.56 0.07 0.58
6.0 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 12/29/2007 22:58:06 12/29/2007 17:58:06 21.7 4,169 5.26 5.28 0.02 0.08
6.3 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 12/26/2007 22:04:56 12/26/2007 17:04:56 21.7 4,163 5.69 5.76 0.07 0.58
7.2 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 12/19/2007 09:30:30 12/19/2007 04:30:30 35.0 4,625 5.72 5.94 0.22 1.50
7.8 SOUTH OF THE FIJI ISLANDS 12/09/2007 07:28:20 12/09/2007 02:28:20 92.7 7,638 6.07 6.15 0.08 1.00
7.4 MARTINIQUE REGION, WINDWARD ISLANDS 11/29/2007 19:00:19 11/29/2007 14:00:19 88.9 1,930 5.92 6.02 0.10 0.58
6.7 PERU-ECUADOR BORDER REGION 11/16/2007 03:12:59 11/15/2007 22:12:59 73.9 2,718 5.82 5.92 0.10 0.17
6.8 ANTOFAGASTA, CHILE 11/15/2007 15:06:00 11/15/2007 10:06:00 21.7 4,183 5.71 5.76 0.05 0.33
6.2 OFFSHORE ANTOFAGASTA, CHILE 11/15/2007 15:03:08 11/15/2007 10:03:08 16.8 4,176 5.71 5.76 0.05 0.33
7.7 ANTOFAGASTA, CHILE 11/14/2007 15:40:53 11/14/2007 10:40:53 37.3 4,138 5.58 5.85 0.27 2.92
7.2 PAGAN REGION, NORTHERN MARIANA ISLANDS 10/31/2007 03:30:20 10/30/2007 23:30:20 154.3 7,566 5.56 5.63 0.07 0.83
6.8 KEPULAUAN MENTAWAI REGION, INDONESIA 10/24/2007 21:02:52 10/24/2007 17:02:52 18.6 10,137 6.35 6.44 0.09 0.83
6.8 SOUTH ISLAND OF NEW ZEALAND 10/15/2007 12:29:37 10/15/2007 08:29:37 15.8 8,951 6.52 6.55 0.03 0.25
6.2 ALASKA PENINSULA 10/02/2007 18:00:08 10/02/2007 14:00:08 29.8 3,867 6.27 6.31 0.04 0.08
7.3 AUCKLAND ISLANDS, NEW ZEALAND REGION 09/30/2007 05:23:34 09/30/2007 01:23:34 6.8 9,191 6.49 6.59 0.10 1.75
6.8 SOUTH OF THE MARIANA ISLANDS 09/30/2007 02:08:29 09/29/2007 22:08:29 6.2 8,005 6.43 6.54 0.11 1.17
7.4 MARIANA ISLANDS REGION 09/28/2007 13:38:58 09/28/2007 09:38:58 162.4 7,493 6.30 6.38 0.08 0.58
6.6 SOUTHEAST OF THE LOYALTY ISLANDS 09/28/2007 01:35:52 09/27/2007 21:35:52 6.2 8,177 6.32 6.34 0.02 0.08
6.3 SOUTHEAST OF THE LOYALTY ISLANDS 09/27/2007 19:57:45 09/27/2007 15:57:45 13.1 8,180 6.12 6.14 0.02 0.08
6.9 NEW IRELAND REGION, PAPUA NEW GUINEA 09/26/2007 12:36:23 09/26/2007 8:36:23 6.2 8,389 6.30 6.32 0.02 0.08
5.2 KEPULAUAN MENTAWAI REGION, INDONESIA 09/13/2007 04:06:10 09/13/2007 00:06:10 6.2 9,994 6.35 6.55 0.20 1.25
7.0 KEPULAUAN MENTAWAI REGION, INDONESIA 09/13/2007 03:35:26 09/12/2007 23:35:26 6.2 10,023 6.35 6.55 0.20 1.58
7.8 KEPULAUAN MENTAWAI REGION, INDONESIA 09/12/2007 23:49:01 09/12/2007 19:49:01 6.2 10,047 5.94 7.05 1.11 1.75
5.1 SOUTHWEST OF SUMATRA, INDONESIA 09/12/2007 23:19:44 09/12/2007 19:19:44 6.2 10,154 5.94 7.05 1.11 1.75
5.3 KEPULAUAN BARAT DAYA, INDONESIA 09/12/2007 17:04:33 09/12/2007 13:04:33 190.9 9,808 6.31 6.34 0.03 0.58
5.9 SOUTHERN SUMATRA, INDONESIA 09/12/2007 16:37:01 09/12/2007 12:37:01 6.2 10,085 6.31 6.34 0.03 0.58
6.0 SOUTHERN SUMATRA, INDONESIA 09/12/2007 14:40:01 09/12/2007 10:40:01 6.8 10,094 5.20 6.81 1.61 3.67
5.3 KEPULAUAN MENTAWAI REGION, INDONESIA 09/12/2007 13:17:15 09/12/2007 09:17:15 6.2 10,103 5.20 6.81 1.61 3.67
5.7 SOUTHERN SUMATRA, INDONESIA 09/12/2007 13:02:03 09/12/2007 09:02:03 6.2 10,076 5.20 6.81 1.61 3.67
5.2 KEPULAUAN MENTAWAI REGION, INDONESIA 09/12/2007 12:21:44 09/12/2007 08:21:44 6.2 10,058 5.20 6.81 1.61 3.67
8.4 SOUTHERN SUMATRA, INDONESIA 09/12/2007 11:10:26 09/12/2007 07:10:26 18.6 10,182 5.20 6.81 1.61 3.67
6.8 WEST COAST OF COLOMBIA 09/10/2007 01:49:11 09/09/2007 21:49:11 6.2 2,357 6.25 6.41 0.16 0.33
7.2 SANTA CRUZ ISLANDS 09/02/2007 01:05:18 09/01/2007 21:05:18 21.7 8,005 6.12 6.26 0.14 0.25
6.6 CENTRAL MID-ATLANTIC RIDGE 08/20/2007 22:42:28 08/20/2007 18:42:28 6.2 3,265 5.97 6.00 0.03 0.08
6.7 SOLOMON ISLANDS 08/16/2007 08:39:27 08/16/2007 04:39:27 1.1 8,283 5.85 5.88 0.03 0.17
6.3 NEAR THE COAST OF CENTRAL PERU 08/16/2007 05:16:58 08/16/2007 01:16:58 21.7 3,546 5.98 6.00 0.02 0.08
8.0 NEAR THE COAST OF CENTRAL PERU 08/15/2007 23:40:58 08/15/2007 19:40:58 25.3 3,480 5.54 6.04 0.50 2.92
6.5 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 08/15/2007 20:22:13 08/15/2007 16:22:13 13.2 4,584 5.85 5.89 0.04 0.17
7.5 JAVA, INDONESIA 08/08/2007 17:04:58 08/08/2007 13:04:58 179.7 10,226 5.56 5.61 0.05 0.83
6.7 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 08/02/2007 03:21:42 08/02/2007 23:21:42 13.0 4,650 5.50 5.56 0.06 0.42
7.2 VANUATU 08/01/2007 17:08:51 08/01/2007 13:08:51 74.6 8,062 5.52 5.55 0.03 0.08
6.9 MOLUCCA SEA 07/26/2007 05:40:16 07/26/2007 01:40:16 15.5 9,152 5.16 5.20 0.04 0.42
6.6 NEAR THE WEST COAST OF HONSHU, JAPAN 07/16/2007 01:13:22 07/16/2007 21:13:22 6.2 6,723 5.40 5.42 0.02 0.08
6.0 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 07/15/2007 13:09:01 07/15/2007 19:09:01 6.2 4,158 5.43 5.49 0.06 0.33
6.7 BOUGAINVILLE REGION, PAPUA NEW GUINEA 06/28/2007 02:52:09 06/28/2007 22:52:09 6.2 8,461 5.01 5.04 0.03 0.33
6.7 OFFSHORE GUATEMALA 06/13/2007 19:29:41 06/13/2007 15:29:41 14.3 1,742 4.44 4.51 0.07 0.50
6.4 SOLOMON ISLANDS 04/01/2007 21:11:33 04/01/2007 17:11:33 6.2 8,377 2.68 3.02 0.34 1.92
6.7 SOLOMON ISLANDS 04/01/2007 20:47:31 04/01/2007 16:47:31 6.2 8,370 2.68 3.02 0.34 2.08
8.0 SOLOMON ISLANDS 04/01/2007 20:39:56 04/01/2007 16:39:56 6.2 8,358 2.68 3.02 0.34 2.08
6.9 VANUATU 03/25/2007 01:08:19 03/24/2007 21:08:19 21.7 8,160 2.70 2.80 0.10 1.17
6.7 NEAR THE WEST COAST OF HONSHU, JAPAN 03/25/2007 00:41:57 03/24/2007 20:41:57 3.1 6,792 2.70 2.80 0.10 1.17
7.2 VANUATU 03/25/2007 00:40:02 03/24/2007 20:40:02 21.7 8,152 2.70 2.80 0.10 1.17
6.7 KEPULAUAN OBI, INDONESIA 02/20/2007 08:04:27 02/20/2007 03:04:27 14.0 9,396 3.28 3.32 0.04 0.25
6.2 CUBA REGION 02/04/2007 20:56:58 02/04/2007 15:56:58 6.2 1,223 3.23 3.29 0.06 0.08
6.7 WEST OF MACQUARIE ISLAND 01/30/2007 04:54:50 01/29/2007 23:54:50 6.2 9,960 3.03 3.09 0.06 0.58
7.3 MOLUCCA SEA 01/21/2007 11:27:42 01/21/2007 06:27:42 6.2 9,289 2.87 2.98 0.11 0.50
8.2 EAST OF THE KURIL ISLANDS 01/13/2007 04:23:20 01/13/2007 23:23:20 6.2 5,758 0.33 3.18 2.85 2.58
6.9 TAIWAN 12/26/2006 12:34:14 12/26/2006 7:34:14 6.2 8,141 2.97 3.17 0.20 1.58
6.4 EAST OF THE KURIL ISLANDS 11/15/2006 11:40:55 11/15/2006 6:40:55 6.2 5,738 3.10 3.85 0.75 2.67
5.3 KURIL ISLANDS 11/15/2006 11:40:03 11/15/2006 6:40:03 6.2 5,790 3.10 3.85 0.75 2.67
6.5 EAST OF THE KURIL ISLANDS 11/15/2006 11:34:58 11/15/2006 6:34:58 6.2 5,712 3.10 3.85 0.75 2.67
5.5 KURIL ISLANDS 11/15/2006 11:33:23 11/15/2006 6:33:23 6.2 5,755 3.10 3.85 0.75 2.67
6.2 EAST OF THE KURIL ISLANDS 11/15/2006 11:29:22 11/15/2006 6:29:22 6.2 5,755 3.10 3.85 0.75 2.67
6.0 EAST OF THE KURIL ISLANDS 11/15/2006 11:28:38 11/15/2006 6:28:38 6.2 5,779 3.10 3.85 0.75 2.67
6.0 KURIL ISLANDS 11/15/2006 11:25:07 11/15/2006 6:25:07 6.2 5,767 3.10 3.85 0.75 2.67
5.6 EAST OF THE KURIL ISLANDS 11/15/2006 11:24:36 11/15/2006 6:24:36 6.2 5,700 3.10 3.85 0.75 2.67
5.6 EAST OF THE KURIL ISLANDS 11/15/2006 11:23:O6 11/15/2006 6:23:06 6.2 5,745 3.10 3.85 0.75 2.67
8.3 KURIL ISLANDS 11/15/2006 11:14:16 11/15/2006 6:14:16 17.7 5,779 3.10 3.85 0.75 2.67
6.5 NEAR THE COAST OF CENTRAL PERU 10/20/2006 10:48:57 10/20/2006 06:48:57 20.6 3,487 3.23 3.41 0.18 0.25
6.6 NEW BRITAIN REGION, PAPUA NEW GUINEA 10/17/2006 01:25:12 10/16/2006 21:25:12 19.9 8,556 4.91 4.95 0.04 0.25
6.0 HAWAII REGION, HAWAII 10/15/2006 17:14:12 10/15/2006 13:14:12 11.7 1,627 4.74 4.79 0.05 0.25
6.7 ISLAND OF HAWAII, HAWAII 10/15/2006 17:07:49 10/15/2006 13:07:49 23.6 1,625 4.74 4.79 0.05 0.25
6.6 KURIL ISLANDS 10/01/2006 09:06:00 10/01/2006 05:06:00 6.2 5,785 4.72 4.78 0.06 0.42
6.0 KURIL ISLANDS 09/30/2006 13:56:16 09/30/2006 13:56:16 6.2 5,799 4.75 4.80 0.05 0.25
6.6 KURIL ISLANDS 09/30/2006 17:50:25 09/30/2006 13:50:25 15.5 5,796 4.75 4.80 0.05 0.25
6.0 GULF OF MEXICO 09/10/2006 14:56:07 09/10/2006 10:56:07 6.2 835 4.02 4.11 0.09 0.08
5.7 NEAR THE EAST COAST OF KAMCHATKA, RUSSIA 09/01/2006 10:25:17 09/01/2006 6:25:17 31.8 5,248 4.18 4.23 0.05 0.42
6.8 BOUGAINVILLE REGION, PAPUA NEW GUINEA 09/01/2006 10:18:52 09/01/2006 6:18:52 28.4 8,363 4.18 4.23 0.05 0.42
6.4 NEAR THE EAST COAST OF KAMCHATKA, RUSSIA 08/24/2006 21:50:39 08/24/2006 17:50:39 43.6 5,762 4.48 4.51 0.03 0.08
7.1 SCOTIA SEA 08/20/2006 3:41:47 08/19/2006 23:41:47 6.2 7,241 4.22 4.27 0.05 0.25
6.0 JAVA, INDONESIA 07/17/2006 10:09:07 07/17/2006 6:09:07 6.2 10,425 3.08 3.20 0.12 1.58
6.2 SOUTH OF JAVA, INDONESIA 07/17/2006 9:13:05 07/17/2006 5:13:05  6.2 10,436 3.08 3.20 0.12 1.58
5.7 SOUTH OF JAVA, INDONESIA 07/17/2006 9:05:17 07/17/2006 5:05:17 6.2 10,478 3.08 3.20 0.12 1.58
7.7 SOUTH OF JAVA, INDONESIA 07/17/2006 8:19:25 07/17/2006 4:19:25 6.2 10,458 3.08 3.20 0.12 1.58
5.3 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 07/08/2006 20:50:14 07/08/2006 16:50:14 1.9 4,625 2.66 2.70 0.04 0.17
6.2 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 07/08/2006 20:40:04 07/08/2006 16:40:04 30.0 4,627 2.66 2.70 0.04 0.17
6.3 ANDREANOF ISLANDS, ALEUTIAN ISLANDS, ALASKA 07/08/2006 20:39:59 07/08/2006 16:39:59 4.3 4,634 2.66 2.70 0.04 0.17
6.1 RAT ISLANDS, ALEUTIAN ISLANDS, ALASKA 06/14/2006 04:46:42 06/14/2006 00:46:42 19.0 4,731 5.64 5.73 0.09 0.75
6.3 RAT ISLANDS, ALEUTIAN ISLANDS, ALASKA 06/14/2006 04:18:46 06/14/2006 00:18:46 23.1 4,734 5.64 5.73 0.09 0.75
5.6 TONGA 05/28/2006 03:36:17 05/27/2006 23:36:17 26.2 7,253 5.57 5.60 0.03 0.08
6.3 NEAR THE EAST COAST OF KORYAKIA, RUSSIA 05/22/2006 11:12:00 05/22/2006 07:12:00 8.4 4,729 5.68 5.76 0.08 0.75
6.8 NIAS REGION, INDONESIA 05/16/2006 15:28:26 05/16/2006 11:28:26 10.1 9,864 5.23 5.28 0.05 0.42
7.4 KERMADEC ISLANDS REGION 05/16/2006 10:39:24 05/16/2006 06:39:24 94.2 7,931 5.07 5.12 0.05 1.08
6.0 FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA 05/10/2006 02:42:54 05/09/2006 22:42:54 26.7 4,213 5.11 5.14 0.03 0.08
7.9 TONGA 05/03/2006 15:26:40 05/03/2006 11:26:40 34.2 7,243 4.90 5.26 0.36 1.67
7.6 KORYAKIA, RUSSIA 04/20/2006 23:25:04 04/20/2006 19:25:04 23.9 4,684 4.61 5.62 1.01 2.25
7.4 MOZAMBIQUE 02/22/2006 22:19:07 02/22/2006 17:19:07 6.8 8,384 4.12 4.29 0.17 1.08
6.6 GULF OF CALIFORNIA 01/04/2006 08:32:30 01/04/2006 03:32:30 8.7 1,939 4.91 5.06 0.15 0.75
7.4 EAST OF THE SOUTH SANDWICH ISLANDS 01/02/2006 06:10:49 01/02/2006 01:10:49 6.2 7,519 5.01 5.15 0.14 1.33
6.8 LAKE TANGANYIKA REGION, CONGO-TANZANIA 12/05/2005 12:19:57 12/05/2005 07:19:57 13.7 4,711 4.61 4.66 0.05 0.58
6.5 SIMEULUE, INDONESIA 11/19/2005 14:10:14 11/19/2005 09:10:14 18.6 9,715 5.67 5.70 0.03 0.25
7.0 OFF THE EAST COAST OF HONSHU, JAPAN 11/14/2005 21:38:51 11/14/2005 16:38:51 6.8 6,503 5.60 5.76 0.16 0.92
7.6 PAKISTAN 10/08/2005 03:50:40 10/07/2005 23:50:40 16.2 7,229 5.31 5.49 0.18 1.75

Real-time water-level data

When a large earthquake has occurred somewhere in the world, click on the image to the right to see if a water-level response was recorded in well 27F2 SOW 019

Well 27F  2 SOW 019

NWISWeb Real-Time Page for Well 27F  2 SOW 019
Note that the diurnal cycles in the water-level record are not in response to earthquakes, but are the effects of earth tides.  Click on the image to the right for a larger version.  Earth tides are a phenomenon similar to ocean tides, but affect our solid earth rather than ocean water levels. Earth tides and even changes in barometric pressure can effect the water levels in some wells. Water levels in the Christiansburg well are "raw data", and thus are not adjusted for these effects. Earth Tides in Well 27F  2 SOW 019

 


additional information

For additional information about hydrologic responses to earthquakes and for information about earthquakes in general, click on the images below:

Earthquakes—Rattling the Earth’s Plumbing System

USGS Fact Sheet 096-03

 

USGS CoreCast
Episode 149
Waves Rippling Through Groundwater
Host: Kara Capelli
  Earthquakes affect Earth’s intricate plumbing system. The magnitude 9.0 earthquake in Japan on March 11, 2011 affected water levels in groundwater wells in many places in the United States. In this episode of CoreCast USGS Geophysicist Evelyn Roeloffs explains this phenomenon.

Hydrologic Effects of the Pymatuning Earthquake of September 25, 1998 in Northwestern Pennsylvania

USGS Water-Resources Investigations Report 99-417

 

Groundwater-Level Response to M5.8 Mineral, Virginia Earthquake, August 23, 2011

Groundwater-Level Response to M5.8 Mineral, Virginia Earthquake, August 23, 2011

 

USGS Earthquake Hazards Program

USGS Earthquake Hazards Program

 

Virginia Groundwater Response to M7.4 Guatemala Earthquake Nov. 7, 2012

YouTube Video of M7.4 Guatemala Earthquake

 

For Additional Information:  Contact David Nelms dlnelms@usgs.gov

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