Puerto Rico is shaking a lot

[cycloneye]

http://rmsismo.uprm.edu/cgi-bin/mkfelt/ ... =view_only



A 3.3 Tremor shaked mainly eastern Puerto Rico. I didn't felt it.



Epicentral Map (PRSN), Last Modification: 2005-01-25 12:30:00 GMT MEMO
FELT EVENT


DATE: January 25, 2005
LOCAL TIME: 00 H 27 M 11 S
LATITUDE: 18.070 N
LONGITUDE: 65.701 W
LOCATION: 16 km SE of Humacao, Puerto Rico
DEPTH: 8.02 km
MAGNITUDE: 3.3 Richter Scale
MAXIMUM INTENSITY: II in Humacao, Modified Mercalli Scale (MM)

COMMENTS:

The Puerto Rico Seismic Network (PRSN) received reports that this minor earthquake was felt in Humacao, Puerto Rico, with an intensity of II in the Modified Mercalli Scale (MM). At the moment of generating this bulletin no damage has been reported.

[sunny]

Wow! Hopefully there was not any damage?

[cycloneye]

Wow! Hopefully there was not any damage?

No damage at all.

[Aslkahuna]

A Modified Mecalli intensity of II is not damaging-in fact it is just barely at the felt level. You need to get up around MM=V before things start coming off of shelves and walls and VII or more for serious damage.

Steve

[cycloneye]

MAG DATE UTC-TIME LAT LON DEPTH LOCATION
y/m/d h:m:s deg deg km

2.9 2005/01/26 13:08:08 17.864 -67.175 3.8 12 km ( 7 mi) S of Pole Ojea, PR
2.9 2005/01/26 02:40:55 19.546 -67.650 55.5 134 km ( 83 mi) NNW of Rafael Hernández, PR
1.4 2005/01/25 07:32:23 18.067 -66.555 18.4 2 km ( 1 mi) N of Coto Laurel, PR
3.3 2005/01/25 04:27:11 18.070 -65.701 8.0 12 km ( 7 mi) SSE of Punta Santiago, PR
3.2 2005/01/24 09:46:45 18.109 -68.115 13.5 85 km ( 53 mi) SE of Higüey, Dominican Republic
1.8 2005/01/24 04:23:23 17.888 -66.796 8.6 12 km ( 7 mi) S of Indios, PR
3.3 2005/01/23 21:34:56 18.703 -65.225 65.8 45 km ( 28 mi) N of Culebra, PR
2.9 2005/01/23 16:47:16 19.306 -67.847 7.4 119 km ( 74 mi) NE of Higüey, Dominican Republic
2.7 2005/01/23 12:00:23 18.769 -66.079 48.7 37 km ( 23 mi) N of Cataño, PR
2.1 2005/01/23 05:11:17 18.521 -66.603 7.0 8 km ( 5 mi) NNW of Garrochales, PR
2.9 2005/01/22 20:24:12 19.274 -67.979 24.9 106 km ( 66 mi) NE of Higüey, Dominican Republic
2.0 2005/01/21 21:36:06 18.093 -67.063 21.8 2 km ( 2 mi) ENE of Sabana Eneas, PR
2.6 2005/01/21 21:17:14 19.166 -66.122 20.0 79 km ( 49 mi) N of Dorado, PR
2.1 2005/01/21 18:52:38 18.400 -67.464 8.2 23 km ( 15 mi) WNW of Rincón, PR
1.1 2005/01/20 17:10:23 17.960 -66.634 2.8 6 km ( 4 mi) SSW of Ponce, PR
2.8 2005/01/20 16:36:17 18.983 -66.766 22.4 56 km ( 35 mi) N of Carrizales, PR
2.7 2005/01/20 14:21:55 18.548 -66.803 18.3 7 km ( 5 mi) NNE of Hatillo, PR
2.8 2005/01/20 13:33:41 19.301 -67.865 24.8 117 km ( 73 mi) NE of Higüey, Dominican Republic
1.5 2005/01/20 07:40:11 17.812 -66.401 10.1 17 km ( 11 mi) S of Jauca, PR
1.4 2005/01/20 06:11:02 17.860 -66.813 9.4 15 km ( 9 mi) S of Indios, PR
1.5 2005/01/19 20:57:55 17.875 -66.793 8.2 14 km ( 8 mi) S of Indios, PR



In only 7 days many tremors haved shaken Puerto Rico with epicenters in the mona passage or in the atlantic NW and NE of PR.Some people say that many shakes is good because the plaques accomodate.I hope that is the case and the NE caribbean doesn't have to deal with a strong quake in the near future.

[Matt-hurricanewatcher]

This could be a before shock before the big one!

[cycloneye]

This could be a before shock before the big one!

No is the other way around the more tremors less energy to be released..

[sunny]

This could be a before shock before the big one!

No is the other way around the more tremors less energy to be released..

I hope this is the case! Be careful down there!

[cycloneye]

The last strong quake that strucked Puerto Rico was in 1918 a 7.3 at ritcher scale that also caused a tsunami at western PR which killed over 300 people.Hopefuly I dont see that in my lifetime or never happens but you never know as earthquakes are not a prediction piece of cake like hurricanes which you can prepare with days ahead.

[Aslkahuna]

What you are seeing is a classic earthquake swarm which could be a precursor to a larger shock or could just be some jitters. However, earthquakes of such small magnitude-no matter how many, have absolutely no impact on the buildup of stress on a fault system nor do they relieve any of it either. It would take 1000 mag 3's to equal the energy of a single mag 5 while the energy release in a MM7.0 is somewhat over 1 million times the release in a m=3.0 so you would need a whole bunch of little shocks over a short period of time to release the strain that a MM7.0 releases in about 15-30 seconds.

Steve

[depotoo]

have any earthquake experts on here?? would love to see your input about what is going on here.

[sunny]

have any earthquake experts on here?? would love to see your input about what is going on here.

Me, too!

[cycloneye]

have any earthquake experts on here?? would love to see your input about what is going on here.

Me, too!

How is New Orleans in terms of quakes? Haved there been a lot,a few or none in the gulf coast?

[sunny]

I looked - no quakes in New Orleans that I could find. Not that I'm complaining, mind you!

[cycloneye]

Good for that region and city as we know it is below sea level.

[southerngale]

I'm glad it wasn't serious cyc and hope nothing stronger occurs. You asked sunny about New Orleans so I did a search for Beaumont, knowing that I had never heard of any earthquakes in this region.

I came across this:

East Texas, especially the region between Austin and Houston, has had a history of minor earthquakes associated with oil field production, sediment loading in the Gulf of Mexico, large deposits of salts (salt domes), and fault stresses since the 1800's. Oil field production is likely responsible for most of this activity. "The East Texas oil field was, at the time of discovery in 1930, the largest field in the Western Hemisphere (...192 million square miles). By the time of the earthquakes [4 in 1957 near Gladewater with the first having a magnitude of 4.7 and felt over an area of 20,000 square miles], more than 3.5 [billion barrels] of oil had been extracted from the field...." Fluid withdrawal is also associated with tremors and land subsidence [sinking] near Beaumont. At one oil field, a 5 acre plot of land sank 160 feet in October 1929. A 7 foot drop in the Houston area between 1943 and 1974 has also been measured. Both of these subsidence actions are thought to be the result of massive withdrawals of oil and water from the underlying strata. Fluid withdrawal, though a major contributor to East Texas seismic activity, does not account for all earthquakes in the region. During a 5 month period in 1964, more than 70 earthquakes with magnitudes up to 4.4 were recorded near Hemphill. Though these tremors are thought to have been caused by sediment loading, "the reason for a burst of activity ...as opposed to random seismicity, is unexplained" (Davis et al. 1, 17-18, 21). South Texas has begun to experience an increase in frequency of earthquakes and related seismic activity in recent years. Areas in and around Bexar and Atascosa counties, particularly near the cities of Seguin, Jourdanton, Pleasanton, and Fashing have been sites for relatively mild earthquakes for several decades. The August 10, 1992 issue of the San Antonio Express (10A) reported that there were at least 4 earthquakes with magnitudes between 2.3 and 3.8 around Jourdanton and Pleasanton from 1991 to 1992. One tremor moved a small house several inches off its foundation in Pleasanton. These tremors have generally been attributed to oil field production, but some are thought to be the result of an increase in fault line activity (Davis et al. 21).

Initially, the perceived lack of seismic activity in Texas was brought into question. We then proceeded to examine historical evidence, which indicates that earthquakes are a growing potential threat for Texas in general and the eastern and southern parts of the state in particular.

Certainly, Texas does not have the kind of seismic activity that the more well known earthquake-prone regions possess. There may never again be a magnitude 6 earthquake in this state. The purpose of this paper has not been to alarm, but rather, to inform those who might be interested that the possibility of earthquakes occurring in Texas not only exists, but that the chances of one happening locally appears to be increasing.

http://lonestar.texas.net/~tstevens/CS/EQTX.html

[sunny]

Wow, Kelly! I had no idea - interesting stuff!

[cycloneye]

Thanks Kelly for posting it.

[cycloneye]

http://temblor.uprm.edu/cgi-bin/new-sea ... mit+Search

Look at list of 62 tremors only this month and still there are some days left of january.


yyyy/mm/dd hh:mm:ss.ss lat.itud lon.gitu dep.t m.a Q Region
-----------------------------------------------------------
2005/01/01 07:45:14.95 17.903N 68.139W 79.5 3.6 C Mona Passage
2005/01/01 23:04:49.85 17.895N 68.504W 94.1 3.8 C Eastern Dominican Republic
2005/01/02 04:54:29.70 17.792N 66.616W 6.4 1.7 C Southern Puerto Rico
2005/01/02 18:42:47.58 18.079N 67.506W 5.9 2.0 C Mona Passage
2005/01/02 21:56:22.18 18.741N 64.709W 14.1 3.7 D Virgin Island Platform
2005/01/03 06:00:09.19 17.980N 66.281W 12.5 2.7 C South Puerto Rico
2005/01/03 12:28:30.70 19.306N 68.493W 13.1 2.8 C Septentrional Fault Zone
2005/01/03 14:17:57.35 17.990N 66.285W 14.2 1.6 C South Puerto Rico
2005/01/03 23:54:34.61 19.017N 65.166W 29.3 3.3 D Sombrero Fault Zone
2005/01/04 00:30:49.51 18.935N 65.205W 26.9 3.2 D Sombrero Fault Zone
2005/01/04 02:58:39.11 19.142N 64.826W 43.1 3.1 D Sombrero Fault Zone
2005/01/04 06:32:02.89 18.465N 67.852W 125.5 2.9 D Mona Passage
2005/01/05 06:26:57.92 18.660N 66.897W 20.7 2.4 C Northern Puerto Rico
2005/01/05 23:08:31.18 18.072N 66.511W 20.0 1.4 C South Puerto Rico
2005/01/06 00:51:28.09 18.052N 67.720W 19.5 3.1 D Mona Passage
2005/01/06 21:00:25.76 18.228N 64.566W 153.8 3.8 C Anegada Passage
2005/01/06 23:30:16.52 18.885N 64.511W 35.6 3.5 D Virgin Island Platform
2005/01/07 20:14:32.25 19.006N 64.503W 61.9 3.2 D Virgin Island Platform
2005/01/08 17:07:49.44 19.247N 67.193W 53.8 2.4 C Mona Canyon
2005/01/09 01:17:25.11 18.226N 66.632W 8.8 1.0 D Central Puerto Rico
2005/01/09 01:38:08.12 18.045N 66.543W 20.6 1.0 C South Puerto Rico
2005/01/09 04:01:45.59 18.025N 68.784W 139.6 3.5 D Eastern Dominican Republic
2005/01/09 05:03:36.19 17.890N 67.049W 7.2 1.4 C Southern Puerto Rico
2005/01/09 19:44:27.05 17.986N 66.533W 21.8 0.9 C South Puerto Rico
2005/01/09 20:33:32.76 17.987N 66.526W 22.2 0.9 C South Puerto Rico
2005/01/11 01:31:54.53 18.985N 67.480W 19.9 2.7 D Mona Canyon
2005/01/11 10:39:04.72 18.080N 66.596W 16.3 0.6 B South Puerto Rico
2005/01/11 18:27:05.53 19.186N 66.221W 30.1 3.0 C 19° N Fault Zone
2005/01/11 23:27:00.98 19.201N 66.206W 28.4 2.6 D 19° N Fault Zone
2005/01/12 09:59:29.34 19.180N 66.218W 26.3 2.5 D 19° N Fault Zone
2005/01/12 17:56:27.61 18.433N 68.250W 101.0 3.0 D Eastern Dominican Republic
2005/01/13 05:52:54.56 18.142N 67.198W 22.8 1.8 C West Puerto Rico
2005/01/14 08:55:42.39 18.040N 66.413W 8.4 0.7 C South Puerto Rico
2005/01/14 23:09:45.17 17.954N 67.036W 6.0 1.6 C Southwest Puerto Rico
2005/01/16 02:34:21.36 18.105N 66.760W 19.5 1.8 B Central Puerto Rico
2005/01/16 09:54:13.42 18.711N 68.916W 166.1 4.0 D Eastern Dominican Republic
2005/01/16 13:41:54.51 17.749N 67.526W 28.1 2.8 C Mona Passage
2005/01/18 14:40:34.78 17.762N 68.078W 61.6 2.7 D Mona Passage
2005/01/18 17:32:50.74 18.044N 66.549W 2.6 1.0 C South Puerto Rico
2005/01/19 10:29:08.74 17.906N 66.932W 9.1 1.9 B Southern Puerto Rico
2005/01/19 12:06:35.80 18.747N 67.477W 21.3 3.2 D Mona Canyon
2005/01/19 20:57:55.84 17.875N 66.793W 8.2 1.5 C Southern Puerto Rico
2005/01/20 06:11:02.41 17.861N 66.813W 9.4 1.4 C Southern Puerto Rico
2005/01/20 07:40:11.26 17.812N 66.401W 10.1 1.5 D Southern Puerto Rico
2005/01/20 13:33:41.38 19.301N 67.866W 24.8 2.8 D Septentrional Fault Zone
2005/01/20 14:21:55.20 18.548N 66.803W 18.3 2.7 C Northern Puerto Rico
2005/01/20 16:36:17.66 18.983N 66.766W 22.4 2.8 C 19° N Fault Zone
2005/01/20 17:10:23.73 17.960N 66.634W 2.8 1.1 C South Puerto Rico
2005/01/21 18:52:38.40 18.400N 67.464W 8.2 2.1 C Mona Canyon
2005/01/21 21:17:14.89 19.166N 66.122W 20.0 2.6 D 19° N Fault Zone
2005/01/21 21:36:06.60 18.093N 67.063W 21.8 2.0 B West Puerto Rico
2005/01/22 20:24:12.03 19.274N 67.979W 24.9 2.9 C Septentrional Fault Zone
2005/01/23 05:11:17.46 18.521N 66.603W 7.0 2.1 C Northern Puerto Rico
2005/01/23 12:00:23.02 18.769N 66.079W 48.7 2.7 C Northern Puerto Rico
2005/01/23 16:47:16.15 19.306N 67.847W 7.4 2.9 D Septentrional Fault Zone
2005/01/23 21:34:56.53 18.703N 65.226W 65.8 3.3 C Sombrero Fault Zone
2005/01/24 04:23:23.13 17.888N 66.796W 8.6 1.8 C Southern Puerto Rico
2005/01/24 09:46:45.28 18.109N 68.115W 13.5 3.2 D Mona Passage
2005/01/25 04:27:11.27 18.070N 65.701W 8.0 3.3 C Out of bound
2005/01/25 07:32:23.75 18.066N 66.554W 18.4 1.4 B South Puerto Rico
2005/01/26 02:40:55.74 19.546N 67.650W 55.5 2.9 D Puerto Rico Trench
2005/01/26 13:08:08.10 17.864N 67.175W 3.8 2.9 C Southern Puerto Rico

[sunny]

I'm no expert - but that doesn't sound too good