El Salvador seismic activity

[Macrocane]

An earthquake swarm began today in the Salvadorian side of the Gulf of Fonseca. 36 quakes have been registered today and 2 of them have been felt (only in the area near the epicenter). It's important to say that it is not directly related to the 5.2 earthquake of this morning they have different origins, the one in the morning occured in the subduction zone and the swarm is located in the Gulf of Fonseca's faults.

These are the details of the two quakes that have been felt in the area:

Date: May 3 2010
Local Time: 10:29
Latitude (N): 13.305
Longitude (W): -87.913
Location: 5 km west of Conchagua, department of La Union
Depth (km): 2.6
Magnitude: 3.3
Intensity: III in Conchagua

Date: May 3 2010
Local Time: 14:29
Latitude (N): 13.305
Longitude (W): -87.913
Location: 5 km west of Conchagua, department of La Union
Depth (km): 2.6
Magnitude: 2.4
Intensity: II in Conchagua

On this map you can see the red spot where the last quake was felt:



http://www.snet.gob.sv/ver/sismologia/monitoreo/sismos+sentidos/

[Macrocane]

Two earthquakes have been felt today in El Salvador, both of them had their epicenter in faults and not in the subduction zone.

Date: Mayo 14 2010
Local Time: 04:51
Latitude (N): 13.945
Longitude (O): -89.368
Location: 5 km south of San Pablo Tacachico (40 km northwest of San Salvador)
Depth (km): 6.0
Magnitude: 2.6
Intensity: II in San Juan Opico

Date: Mayo 14 2010
Local Time: 09:56
Latitude (N): 13.712
Longitude (O): -89.239
Location: San Salvador Metropolitan area
Depth (km): 5.7
Magnitude: 2.9
Intensity: III in San Salvador

[vbhoutex]

I have a question about the seismic activity in your area. Is the amount unusual compared to what is "normal" or does it seem like a lot since we are now seeing it reported here?

[Macrocane]

The experts have not mentioned if the activity has been above normal but IMO it has been a little above normal this year, especially in January and May.

[Macrocane]

During May and June only weak earthquakes were registered (less then 4.0) so I didn't post the info but in July the intenisty and frequency of the earthquakes has increased, here is the info of the last seven earthquakes:

Date, magnitude, location
July 02, 4.1, in the coast in front of Guatemala-El Salvador border
July 03, 4.0, in the coast in front of Guatemala-El Salvador border
July 04, 4.4, in the coast in front of Guatemala-El Salvador border
July 08, 2.9, inland west of San Salvador.
July 09, 4.0, 45 km south of Usulutan (east coast).
July 13, 4.2, in the coast in front of Guatemala-El Salvador border

And the most recent and strongest:
Fecha: July 15 2010
Local Time: 18:06
Latitude (N): 12.797
Longitude (W): -88.651
Location: 45 Km. south of San Juan del Gozo Peninsula department of Usulutan
Depth (km): 32
Magnitude: 5.2
Intensity: IV in San Salvador

According to USGS it had a magnitude of 4.9 and a depth of 64 km http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/us2010yuab.php

[Macrocane]

The subduction zone near Guatemala and El Salvador border continues to be very active, the latest quake:

According to the SNET:
Date: July 25 2010
Local Time: 20:18
Latitude (N): 13.523
Longitude (W): -90.698
Location: Offshore Guatemala.
Depth (km): 19.4
Magnitude: 4.9
Intensity: II in San Salvador

According to USGS:
Magnitude 4.5
Date-Time Monday, July 26, 2010 at 02:18:38 UTC
Sunday, July 25, 2010 at 08:18:38 PM at epicenter
Location 13.560°N, 90.641°W
Depth 66.8 km (41.5 miles)
Region OFFSHORE GUATEMALA
Distances 85 km (50 miles) S of Escuintla, Guatemala
90 km (55 miles) W of Acajutla, El Salvador
120 km (75 miles) S of GUATEMALA, Guatemala
1110 km (690 miles) SE of MEXICO CITY, D.F., Mexico
Location Uncertainty horizontal +/- 25.5 km (15.8 miles); depth +/- 10.3 km (6.4 miles)
Parameters NST= 78, Nph= 80, Dmin=153.6 km, Rmss=1.36 sec, Gp=187°,
M-type=body wave magnitude (Mb), Version=6



Event ID us2010zeae

[Macrocane]

A quake was felt this morning in Guatemala and El Salvador, the epicenter was off Guatemala coast:

SNET:
Date: August 18 2010
Local Time: 09:12
Latitude (N): 13.865
Longitude (W): -90.646
Location: Guatemala coast
Depth (km): 92
Magnitude: 5.1
Intensity: IV in San Salvador

USGS:

Magnitude: 4.8
Date-Time: Wednesday, August 18, 2010 at 15:12:35 UTC
Wednesday, August 18, 2010 at 09:12:35 AM at epicenter
Location: 13.980°N, 90.453°W
Depth: 114.5 km (71.2 miles) set by location program
Region: GUATEMALA
Distances: 37 km (23 miles) SSW (205°) from Cuilapa, Santa Rosa, Guatemala
50 km (31 miles) SE (135°) from Escuintla, Escuintla, Guatemala
59 km (36 miles) SSE (161°) from Amatitl�n, Guatemala, Guatemala
63 km (39 miles) SSE (166°) from Villa Nueva, Guatemala, Guatemala
73 km (45 miles) S (175°) from GUATEMALA CITY, Guatemala
Location Uncertainty: horizontal +/- 13.1 km (8.1 miles); depth fixed by location program
Parameters: NST= 54, Nph= 54, Dmin=724.6 km, Rmss=1.25 sec, Gp=187°,
M-type=body wave magnitude (Mb), Version=Q
Source: USGS NEIC (WDCS-D)
Event ID: us2010aca2

[Macrocane]

Another one in the same area as yesterday:

SNET:
Date: 19 de Agosto de 2010
Local Time: 16:13
Latitude (N): 13.913
Longitude (W): -91.223
Location: Guatemala coast.
Depth (km): 17
Magnitude: 5.4
Intensity: III in San Salvador.

USGS:
Magnitude: 5.2
Date-Time: Thursday, August 19, 2010 at 22:13:02 UTC
Thursday, August 19, 2010 at 04:13:02 PM at epicenter
Time of Earthquake in other Time Zones
Location: 14.078°N, 91.123°W
Depth: 61.5 km (38.2 miles)
Region: GUATEMALA
Distances: 45 km (25 miles) SW of Escuintla, Guatemala
90 km (55 miles) SW of GUATEMALA, Guatemala
95 km (60 miles) SSE of Quetzaltenango, Guatemala
1035 km (650 miles) ESE of MEXICO CITY, D.F., Mexico
Location Uncertainty: horizontal +/- 8 km (5.0 miles); depth +/- 3.3 km (2.1 miles)
Parameters: NST=117, Nph=135, Dmin=744.7 km, Rmss=0.96 sec, Gp=122°,
M-type=body wave magnitude (Mb), Version=6
Source: USGS NEIC (WDCS-D)
Event ID: us2010adcg

[Macrocane]

The strongest earthquake in El Salvador since January 18 was felt this morning, thankfully there are no reports of damages or deaths:

According to the SNET:

Date: December 20 2010
Local Time: 11:21
Latitude (N): 12.946
Longitude (W): -88.826
Location: 30 Km south of Lempa River mouth, Departament of Usulutan
Depth (km): 43
Magnitude: 5.5
Intensity: V in San Salvador

According to USGS:

Magnitude 5.6
Date-Time Monday, December 20, 2010 at 17:21:26 UTC
Monday, December 20, 2010 at 11:21:26 AM at epicenter
Location 13.017°N, 88.629°W
Depth 69.7 km (43.3 miles)
Region OFFSHORE EL SALVADOR
Distances 41 km (26 miles) SSW (210°) from Usulutan, Usulutan, El Salvador
61 km (38 miles) SSE (154°) from Zacatecoluca, La Paz, El Salvador
70 km (44 miles) SW (224°) from San Miguel, San Miguel, El Salvador
93 km (58 miles) SE (141°) from SAN SALVADOR, El Salvador
Event ID usc0000r8c

[Macrocane]

A new moderate earthquake occured yesterday (January 3) in a similar location of the december 20 one:

USGS:

Magnitude 4.7
Date-Time Tuesday, January 04, 2011 at 00:49:43 UTC
Monday, January 03, 2011 at 06:49:43 PM at epicenter
Time of Earthquake in other Time Zones
Location 13.203°N, 89.106°W
Depth 65.5 km (40.7 miles)
Region OFFSHORE EL SALVADOR
Distances 55 km (35 miles) S of SAN SALVADOR, El Salvador
90 km (55 miles) ESE of Acajutla, El Salvador
100 km (60 miles) SSE of Santa Ana, El Salvador
1275 km (790 miles) ESE of MEXICO CITY, D.F., Mexico
Location Uncertainty horizontal +/- 23.7 km (14.7 miles); depth +/- 0.4 km (0.2 miles)
Parameters NST=143, Nph=185, Dmin=55.7 km, Rmss=1.11 sec, Gp=158°,
M-type=body wave magnitude (Mb), Version=7
Source USGS NEIC (WDCS-D)
Event ID usc0000ylt

SNET:
Date: January 3 2011
Local Time: 18:49
Latitude (N): 13.03
Longitude (W): -89.262
Location: 40 kilometers south of Toluca, department of La Libertad.
Profundidad (km): 43
Magnitude: 5.3
Intensity: IV in San Salvador

[Macrocane]

Two more earthquakes have occured in the subduction zone, one yesterday and one today. The info according to the SNET:

Date: January 4 2011
Local Time: 20:10
Latitude (N): 13.002
Longitude (O): -89.256
Location: 40 Km south of San Diego Beach, Department of La Libertad
Depth (km): 35
Magnitude: 4.4
Intensity: III en San Salvador

Date: January 5 2011
Local Time: 02:59
Latitude (N): 12.917
Longitude (O): -89.148
Location: 50 Km south of La Zunganera Beach, Department of La Paz
Depth (km): 32
Magnitude: 4.2
Intensity: II en San Salvador

[Macrocane]

And yet another earthquake was felt yesterday in El Salvador, the epicenter again in the subduction zone, no damages were reported.

SNET
Date: January 11 2011
Local Time: 19:05
Latitude (N): 12.283
Longitude (O): -90.315
Location: Offshore Guatemala-El Salvador border
Depth (km): 35
Magnitude: 5.0
Intensity: III in San Salvador

USGS
Magnitude 5.1
Date-Time
* Wednesday, January 12, 2011 at 01:05:37 UTC
* Tuesday, January 11, 2011 at 07:05:37 PM at epicenter
* Time of Earthquake in other Time Zones
Location 12.589°N, 90.017°W
Depth 51.1 km (31.8 miles)
Region OFF THE COAST OF EL SALVADOR
Distances 115 km (70 miles) S of Acajutla, El Salvador
150 km (95 miles) SW of SAN SALVADOR, El Salvador
160 km (100 miles) SSW of Santa Ana, El Salvador
1230 km (770 miles) SE of MEXICO CITY, D.F., Mexico
Location Uncertainty horizontal +/- 17.5 km (10.9 miles); depth +/- 1.2 km (0.7 miles)
Parameters NST=303, Nph=331, Dmin=148.1 km, Rmss=1.04 sec, Gp=119°,
M-type=body wave magnitude (Mb), Version=9
Source
* USGS NEIC (WDCS-D)
Event ID usc00011q7

[Macrocane]

TENTH ANNIVERSARY OF THE JANUARY 13 2001 EARTHQUAKE IN EL SALVADOR

10 years ago at 11:35 am El Salvador had one of its saddest and scariest experiences of its history when a 7.6 magnitude earthquake occured offshore the country in the subduction zone. The earthquake lasted for 45 seconds and was felt not only in El Salvador but as far as southern Mexico and western Costa Rica. The earthquake caused 944 deaths, 5565 injuries, 1364000 people were left homeless (that was 25% of the total population of the country at that time), more than 277000 homes were destroyed or heavily damaged, 19 hospitals were damaged and 445 important landslides were registered, the damages were estimated in US$ 1.6 billion being the costliest natural disaster in El Salvador's history.

I remember it as a horrible experience, it felt so long that seemed like it was never going to end, everybody remained outside their houses the whole day, some people slept in the garages or in the streets, in my house there were some minor damages, our glasses and dishes fell from the cabinets and were broken, one of the TV's was also destroyed, the walls had some shallow cracks and fissures but thankfully we were not injured. Actually San Salvador escaped the worst but several other towns and cities were almost completely destroyed including Santa Tecla wich is a city that is part of metro San Salvador. In the biggest cities we were without power for 12 hours and the only way to get info and news was with the radios of the cars or radios with batteries, we were without water for 2 or 3 days as well but that was nothing compared with other locations that didn't have water service for weeks.

The next day the newspapers and TV news showed the true magnitude of the tragedy and the local media gave special coverage to the rescue of the bodies in Las Colinas neighborhood in the city of Santa Tecla where 200 houses were buried because of a landslide killing more than 400 people.

In the first 2 days the aftershoks occured every 2 or 3 hours later they became less frequent but we got aftershoks for an entire year. Exactly one month later there was another major earthquake that was not considered an aftershok as the origin was in an inland fault and not in the subduction zone but that will be another story.

I hope the country never experiences again a disaster of such magnitude. Here's a picture of Las Colinas neighborhood a couple of days before the earthquake:

[Macrocane]

An earthquake swarm has developed in Los Naranjos, that town is in the mountains of southwest El Salvador and it is one of the places with highest seismic activity on the country although no historical major earthquakes have had their epicenter there. Since yesterday 3 earthquakes have been felt in that area, as you can see ther magnitude is low but they have been very shallow, they're that kind of quakes that are felt only a few kilometers around the epicenter.

According to the SNET:

Jan 28 2011
Local Time 16:48
Magnitude 2.9
Depth 3 km

Jan 29 2011
Local Time 05:22
Magnitude 2.6
Depth 6.8 km

Jan 29 2011
Local Time 06:04
Magnitude 2.7
Depth 6.8 km

The red point in this image shows the epicenter:

[Macrocane]

The earthquake swarm in Los Naranjos today 2 earthquakes have been felt in that area, plus 2 other earthquakes occured in the subduction zone, one last night and another one today before dawn. This is the information of those 4 earthquakes:

Jan 30 2011
Local Time 21:50
Magnitude 4.5
Depth 50.5 km
Location 30 km south of Toluca beach (offshore)

Jan 31 2011
Local Time 01:41
Magnitude 3.0
Depth 6 km
Location Los Naranjos

Jan 31 2011
Local Time 04:23
Magnitude 4.1
Depth 32.8 km
Location 30 km south of Barra Salada Beach (offshore)

Jan 31 2011
Local Time 15:28
Magnitude 2.3
Depth 2.6 km
Location Los Naranjos

[Macrocane]

February 13 was the 10th anniversary of the second major earthquake that hit El Salvador on 2001. This 2nd earthquake struck El Salvador exacly a month later than the other earthquake and produced again a large amount of damage and a high death toll, one important thing to mention is that this 2nd earthquake was not an aftershock of the 1st one, the February quake had its origin in a fault located inland in Central El Salvador and the January one had its origin offshore in the subduction zone.

The earthquake occured at 8:15 am (local time), I remember I was at school when it started to shake, then it got stronger and stronger and everybody went out of the classrooms, thankfully there were no injuries in my school but we were very scared, then I looked for my little sister and we waited for our parents to come. When finally my dad picked us it took 2 hour for us to get home when normally it wouldn't be more than 20 minutes as there were traffic jams everywhere. After that there were 3 weeks without school because of the aftershocks from the 2 earthquakes.

The official report says that the February 13 earthquake caused:
-315 deaths
-3400 injuries
-275 000 homeless
-61500 homes heavily damaged or destroyed
-111 schools destryed
-5 damaged hospitals
-US$ 350 millions in damages

The two earthquakes killed 1300 people, there were more than 1.6 million of people homeless (almost 30% of El Salvador's population at the time) and US$ 2 billion in damages

[Macrocane]

A moderate earthquake has occurred tonight offshore El Salvador/Nicaragua, actually is the strongest earthquake this year so far in El Salvador. Fortunately there have been no reports of damages yet.

USGS
Magnitude 5.4
Date-Time
* Wednesday, February 23, 2011 at 03:01:40 UTC
* Tuesday, February 22, 2011 at 09:01:40 PM at epicenter
* Time of Earthquake in other Time Zones
Location 12.556°N, 87.663°W
Depth 69.6 km (43.2 miles)
Region NEAR THE COAST OF NICARAGUA
Distances 55 km (35 miles) W of Chinandega, Nicaragua
85 km (55 miles) W of Leon, Nicaragua
160 km (100 miles) WNW of MANAGUA, Nicaragua
1440 km (900 miles) ESE of MEXICO CITY, D.F., Mexico
Location Uncertainty horizontal +/- 16 km (9.9 miles); depth +/- 1.7 km (1.1 miles)
Parameters NST=311, Nph=325, Dmin=171.4 km, Rmss=0.96 sec, Gp=104°,
M-type=body wave magnitude (Mb), Version=7
Source
* USGS NEIC (WDCS-D)
Event ID usb0001jbd

SNET
Date: February 22, 2011
Local Time: 21:01
Latitude (N): 12.378
Longitude (W): -87.814
Location: 90 km South of Gulf of Fonseca
Depth (km): 36
Magnitude: 5.7
Intensity: III in San Salvador

[Macrocane]

Three earthquakes occurred between 22:00 and 0:00 local time, one of them with origin in the subduction zone and the other two in a fault line northwest of San Salvador. The info according to SNET:

Date: February 24, 2011
Local Time: 22:02
Latitude (N): 13.74
Longitude (W): -89.25
Location: Northwest of San Salvador
Depth (km): 1.1
Magnitude: 2.2
Intensity: II in San Salvador

Date: February 24, 2011
Local Time: 22:55
Latitude (N): 12.90
Longitude (W): -88.92
Location: 40 km south of Bocana Cordoncillo (offshore)
Depth (km): 21.1
Magnitude: 4.2
Intensity: III in San Salvador

Date: February 24, 2011
Local Time: 23:56
Latitude (N): 13.74
Longitude (W): -89.26
Location: Northwest of San Salvador
Depth (km): 4
Magnitude: 2.3
Intensity: II in San Salvador

[Macrocane]

The seismic activity continues in El Salvador, in less than 24 hours 4 earthquakes occurred in the subduction zone (offshore El Salvador), the data according to the SNET:

Date: March 1, 2011
Local Time: 08:56
Latitude (N): 12.82
Longitude (W): -88.94
Location: 50 km south of Bocana Cordoncillo
Depth (km): 32.1
Magnitude: 4.1
Intensity: II in San Salvador

Date: March 1, 2011
Local Time: 17:26
Latitude (N): 13.33
Longitude (W): -90.23
Location: 45 km southwest of Paz River mouth
Depth (km): 22.1
Magnitude: 3.5
Intensity: I in San Salvador

Date: March 2, 2011
Local Time: 01:18
Latitude (N): 12.83
Longitude (W): -88.62
Location: 40 km south of San Juan del Gozo Peninsula
Depth (km): 32.6
Magnitude: 3.5
Intensity: I in San Salvador

Date: March 2, 2011
Local Time: 02:24
Latitude (N): 13.16
Longitude (W): -89.37
Location: 35 km south of Majahual Beach
Depth (km): 51.9
Magnitude: 3.6
Intensity: II in San Salvador

[Macrocane]

An earthquake occured this morning in offshore Nicaragua but was felt in the Gulf of Fonseca area:

SNET
Date: March 11 2011
Local Time: 10:57
Latitude (N): 12.2
Longitude (W): -87.968
Location: Offshore Nicaragua.
Depth (km): 15.6
Magnitude: 4.8
Intensity: I in La Union.

USGS
Magnitude 4.8
Date-Time
* Friday, March 11, 2011 at 16:54:52 UTC
* Friday, March 11, 2011 at 10:54:52 AM at epicenter
* Time of Earthquake in other Time Zones
Location 12.304°N, 87.514°W
Depth 64.3 km (40.0 miles)
Region NEAR THE COAST OF NICARAGUA
Distances 52 km (32 miles) SW of Chinandega, Nicaragua
70 km (43 miles) WSW of Leon, Nicaragua
136 km (84 miles) W of MANAGUA, Nicaragua
1475 km (916 miles) ESE of MEXICO CITY, D.F., Mexico
Location Uncertainty horizontal +/- 25.2 km (15.7 miles); depth +/- 2.2 km (1.4 miles)
Parameters NST=123, Nph=129, Dmin=195.9 km, Rmss=1.37 sec, Gp=148°,
M-type=body wave magnitude (Mb), Version=7
Source
* USGS NEIC (WDCS-D)
Event ID usc0001yr5