The caribbean area is shaking a lot

[cycloneye]

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

Puerto Rico has felt many tremors as link below shows in this month being the last one today.

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

But in the rest of the NE caribbean tremors and more stronger quakes haved occured with little damage.


15-FEB-2005 04:31:45 15.71 -61.60 4.3 10.0 LEEWARD ISLANDS
14-FEB-2005 18:05:58 15.65 -61.66 5.6 10.0 LEEWARD ISLANDS
08-FEB-2005 02:18:23 15.46 -61.27 5.2 118.8 LEEWARD ISLANDS
08-FEB-2005 02:18:06 15.57 -61.15 4.1 120.0 LEEWARD ISLANDS
29-JAN-2005 14:45:33 15.68 -61.70 4.7 10.0 LEEWARD ISLANDS
29-JAN-2005 06:36:10 19.66 -65.39 5.0 53.0 PUERTO RICO REGION
28-JAN-2005 18:05:58 19.66 -65.42 4.7 37.0 PUERTO RICO REGION
25-JAN-2005 18:37:11 11.00 -58.60 4.8 10.0 NORTH ATLANTIC OCEAN

The key question is if those movements are a precursor of a big one or they are liberating energy at the caribbean plaque.

[HUC]

I hope these quakes are not precursors.....Here,the latest quake of february the 14th,was very strongly felt,and i can say(i was in the 4th floor) that the whole bulding was shaking,and rooling very bad;some parts of cliffs broke,and felt in the sea.
We are rather tired since november the 21th,with what the scientits are calling"afterschocks",and everybody are asking if a big one is not in store for the carribean.Really,i hope that i will never see a quake of magnitude 7.Guys,a 6.4,as the one of november is really a very difficult experience!!!!!PRAY GOD TO SPARE US...........

[Aquawind]

Bummer. I am glad we don't have the ground shaking regular reminders here in Florida. Tsunami is fresh in everyones mind as well. Sounds highly annoying..

Paul

[Aslkahuna]

Aftershocks are very readily identifiable so if they are being called aftershocks then they probably are. However, again it's very important to note that shocks under about MM6.0 have little or no effect upon the release of strain on a locked fault segment. One could get a swarm of foreshocks prior to a larger event but foreshocks would exhibit different characteristics of aftershocks. The big problem is that foreshocks are not usually identified as such until after the main shock has occurred. For example, it's now known that the 1906 Northern California Earthquake was a foreshock/main shock sequence with a MM6.5 foreshock occurring about a minute before the main MM7.7 shock. But this sequence was not discovered until relatively recently.

Steve

[HURAKAN]

Luis, can does earthquakes be related to Montserrat or any other active volcano in the area?

[Aslkahuna]

Not with those depths. The locations and depths indicate we have three separate sequences going on right now. An aftershock sequence, a couple of very deep shocks, and a couple of unrelated ones. Volcanic earthquakes related to magma movement would be much shallower and with a smaller footprint.

Steve

[cycloneye]

Luis, can does earthquakes be related to Montserrat or any other active volcano in the area?

No not related to that volcano.There is the Anegada fault near the Virgin Islands and the Mona channel fault west of Puerto Rico that are fairly active.

For those who dont know anout this volcano that has awaken since 1995 at link you will see it.


http://www.geo.mtu.edu/volcanoes/west.indies/soufriere/

[msbee]

I haven't felt any of those tremors here on St. maarten but I know people who have. it seems to depend on where you are located and what you are doing at the time.

Is the amount of tremors actually unuusual historically, Luis?
do you know?

Yeras ago my husband and I were on Saba on the mountain hiking. we met a group of scientists who were in the caribbean studying tremors in the region.
Now this was years ago and they told us then, that between the USVI and St. maarten, there regularly occur appoximately 300 tremors daily. These tremors are very mild of course and are all located deep in the ocean. They rarely are felt on land.
we were astounded at the time, having no idea that the region
was so active.
that's why I wonder if the acitvity is increasing or not.
Barbara

Every day it shakes many times but they are very minuscular movements that the seismografs dont register.But then some more strong tremors are registered by the instruments from 2.0 and above.Fortunnally we are located in a plaque that is not too active and the faults are also not very active but once in 80 years a big quake can happen in the caribbean and that is why in Puerto Rico some people are worried after the 1918 7.0 quake in western PR that a big one may come soon.

[cycloneye]

I haven't felt any of those tremors here on St. maarten but I know people who have. it seems to depend on where you are located and what you are doing at the time.

Is the amount of tremors actually unuusual historically, Luis?
do you know?

Yeras ago my husband and I were on Saba on the mountain hiking. we met a group of scientists who were in the caribbean studying tremors in the region.
Now this was years ago and they told us then, that between the USVI and St. maarten, there regularly occur appoximately 300 tremors daily. These tremors are very mild of course and are all located deep in the ocean. They rarely are felt on land.
we were astounded at the time, having no idea that the region
was so active.
that's why I wonder if the acitvity is increasing or not.
Barbara

Every day it shakes many times but they are very minuscular movements that the seismografs dont register.But then some more strong tremors are registered by the instruments from 2.0 and above.Fortunnally we are located in a plaque that is not too active and the faults are also not very active but once in 80 years a big quake can happen in the caribbean and that is why in Puerto Rico some people are worried after the 1918 7.0 quake in western PR that a big one may come soon.

[cycloneye]

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

This afternoon another quake this time a 4.2 shaked NW Puerto Rico.I felt a little bit this one as I was not moving in my chair.At link above there is more information.

[Anonymous]

Could this cause a tsunami on the US coast?? My guess would be no but could happen on the south american coast if the quakes were big enough. Any idea?

[cycloneye]

Could this cause a tsunami on the US coast?? My guess would be no but could happen on the south american coast if the quakes were big enough. Any idea?

Canary Islands Volcano Could Trigger Monster Tsunami
Powered by CDNN - CYBER DIVER News Network
by SUSAN SCHLACHTER
The eruption of a volcano in the Canary Islands could trigger a ''mega-tsunami'' that would devastate Atlantic coastlines with waves as high as 330 feet, scientists said on Wednesday.

They said an eruption of the Cumbre Vieja volcano on La Palma, part of the Spanish island chain off West Africa, was likely to cause a massive chunk of rock to break off, crashing into the sea and kicking up huge walls of water higher than any other in recorded history.

The tsunami would be capable of traveling huge distances at up to 500 miles an hour, the scientists said in a research paper to be published in September's Geophysical Research Letters.

Simon Day, of the Benfield Greig Hazard Research Centre at the University College of London, said that as the volcano was not erupting at present, the short-term and medium-term risks were ''negligible.''

But Cumbre Vieja should be monitored closely for any signs of activity so that emergency services could plan an effective response, he said.

''Eruptions of Cumbre Vieja occur at intervals of decades to a century or so and there may be a number of eruptions before its collapse,'' said Day, who collaborated on the research with Steven Ward of the University of California.

''Although the year-to-year probability of a collapse is therefore low, the resulting tsunami would be a major disaster with indirect effects around the world.''

WEST SAHARA TO BEAR BRUNT

The effects would spread north, west and south of the Canaries, with the west Sahara bearing the worst of the wave's energy.

The energy released by the collapse would be equal to the electricity consumption of the entire United States in half a year.

Immediately after the landslide, a dome of water 900 meters (3,000 feet high) and tens of miles wide would form, only to collapse and rebound.

As the landslide rubble moved deeper under water, a tsunami would develop. Within 10 minutes, the tsunami would have moved a distance of almost 155 miles.

On the west Saharan shore, waves would probably reach heights of 330 feet.

Florida and the Caribbean, the final north Atlantic destinations to be affected by the tsunami, would have to brace themselves for 165 foot waves some eight to nine hours after the landslide.

Wave heights toward Europe would be smaller, but substantial waves would hit the coasts of Britain, Spain, Portugal and France.

The research paper estimated water would penetrate several miles inland and that the devastation would cause trillions of dollars in damage.


If a tsunami reaches the US east coast it would come from that area.

[wxcrazy]

Aftershocks are very readily identifiable so if they are being called aftershocks then they probably are. However, again it's very important to note that shocks under about MM6.0 have little or no effect upon the release of strain on a locked fault segment. One could get a swarm of foreshocks prior to a larger event but foreshocks would exhibit different characteristics of aftershocks. The big problem is that foreshocks are not usually identified as such until after the main shock has occurred. For example, it's now known that the 1906 Northern California Earthquake was a foreshock/main shock sequence with a MM6.5 foreshock occurring about a minute before the main MM7.7 shock. But this sequence was not discovered until relatively recently.

Steve

Yeah, foreshocks are difficult to undersand because they occur so quickly before the main shock, but aftershocks are suppose to wind down not wind up or staty at 5 or 6's.

[HurricaneBill]

I thought I read somewhere that tsunamis triggered by volcanic eruptions weaken quicker than tsunamis triggered by powerful earthquakes.

Than again, there was Krakatoa.

[Aslkahuna]

There have been only two global tsunamis that have been recorded-the last one was from the big shock of last December 26th which showed up as small rises on the tide guages in Europe and along the coasts of the Pacific Basins (except at Manzanillo where an 8 foot rise occurred). the only other one was from Krakatau. Cuba, Hispaniola, and Puerto Rico would tak up much of the nergy of a Caribbean tsunami before it could reach the east coast. As far as an Atlantic tsunami is concerned, the Barrier Islands off large portions of the US east coast plus the extensive shoaling offshore could probably dissipate a lot of the energy of the tsunami before it hit the mainland. Unprotected areas of the coast would not be so lucky.

Steve

[HUC]

Yes,the problem is that teh quake of 14th february in my area,was 5.7,which is largely over what a "normal " afterschock should be,after the 6.4 quake of november 21th.See the topic that i posted "Latest news about the Leeward islands earthquake" on this board.