Puerto Rico

[thirtyhz]

Nothing.  Not even ONE quake in the Pueto Rican subduction area.

I've never seen this before.  This gives me a REALLY BAD feeling.
http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/PR10/13.23.-71.-61.php

1:30 pm Saturday 3/6/2010

[AnnOther]

pardon my ignorance.....
but why is this unusual?    ....how often should there be quakes here?   ....for how long has it been too quiet?

[thirtyhz]

Ann, today is the first day in over a year of watching that particular area (realistically, more like two years) that I've seen ZERO quake activity.  I'd written about Puerto Rico on the pre-hack TRC many times over the last two years.

Significant?  Yes.  Puerto Rico sits on the edge of a deep sea floor subduction zone....at the edge of the Atlantic and Caribbean Plates.  This is an active zone....and shares sea space (along the same plate boundary) with Haiti. 

Two immediate things come to mind.
 Active subduction has stopped (no quakes).
 
The subduction activity has stopped because the North American plate is no longer pushing against the Pacific Plate.  Which it should be....because the Pac Plate isn't fixed in location...it moves constantly, banging back and forth against the fixed plates on it's borders.

This lack of Puerto Rican activity coincides with the Chilean quake.  This all spells trouble on the Pacific Plate.

[sparrow]

30, is possible Haiti,quake temporarily relieved the built up stress?

I will say there are many interesting observations being made lately. I don't know if these events are linked or even unique , perhaps just people trying to make sense of what they are seeing, like cloud shapes.

[thirtyhz]

Could be sparrow.  But PR was rocking all the way up to today. Then nothing.

Maybe the Chilean shake (and aftershocks) was the vent. 

Subduction zones do have the ability to become dormant, and this could be the case.  We shall see.

And yes, I'm with you on the "seeing things".  I've been of that mindset recently too.  Alot.

[shy]

I've never before seen the USGS Puerto Rico map void of eq either!  I had been wondering about possible displacement of seismic stress towards the New Madrid area--MO had a lot lately--& (correctly or not) wondering about SE Canada (& in relationship to the New Madrid). . . . ?   

MAP 2.6 2010/03/06 15:09:25    45.970 -75.369  9.7   ONTARIO-QUEBEC BORDER REGION, CANADA
MAP 2.6 2010/03/06 13:18:01    46.958 -70.734  0.8   SOUTHERN QUEBEC, CANADA
MAP 3.8 2010/02/28 03:51:24    45.726 -74.456  7.0   ONTARIO-QUEBEC BORDER REGION, CANADA

MAP 1.6  2010/03/06 04:08:19 36.486 -89.534 8.0   8 km ( 5 mi) ESE of Marston, MO
MAP 1.7  2010/03/06 04:06:43 36.486 -89.534 8.4   8 km ( 5 mi) ESE of Marston, MO
MAP 1.7  2010/03/03 07:42:32 36.783 -89.357 8.3 3 km ( 2 mi) E of East Prairie, MO
MAP 1.6  2010/03/02 23:59:47 36.790 -89.340 8.1 4 km ( 3 mi) SSW of Anniston, MO
MAP 3.7  2010/03/02 19:37:35 36.788 -89.357 8.2 3 km ( 2 mi) ENE of East Prairie, MO

MAP 3.1  2010/03/05 20:35:13 35.608 -96.783 5.0 3 km ( 2 mi) E of Sparks, OK
MAP 2.5  2010/03/03 04:35:17 35.549 -97.282 5.0 2 km ( 1 mi) SSE of Jones, OK
MAP 1.6  2010/03/05 08:42:24 35.284 -92.404 3.0 4 km ( 3 mi) SSE of Twin Groves, AR
MAP 1.2  2010/03/03 04:18:49 36.205 -89.480 6.3 7 km ( 4 mi) S of Ridgely, TN
MAP 1.1  2010/02/28 09:54:06 35.251 -92.397 6.8 3 km ( 2 mi) NNW of Greenbrier, AR
MAP 0.2  2010/02/28 09:53:57 35.270 -92.395 3.7 5 km ( 3 mi) N of Greenbrier, AR

[thirtyhz]

That's another possibility shy.  The New Madrid has shown marked increase in activity over the last few days.

But again today, nothing in Puerto Rico.  That's impossible to believe, given the amount of activity this region has seen over the 48 months.

3 days and counting.  Unbelievable.

[shy]

3.5 Magnitude
Date-Time Monday, March 08, 2010 at 16:51:26 UTC
Monday, March 08, 2010 at 12:51:26 PM at epicenter
 
Location 17.939°N, 68.503°W
Depth 74.5 km (46.3 miles)
Region DOMINICAN REPUBLIC REGION
Distances 74 km (46 miles) SE (138°) from La Romana, La Romana, Dominican Republic
79 km (49 miles) SSE (164°) from Higüey, La Altagracia, Dominican Republic
103 km (64 miles) SE (124°) from San Pedro de Macorís, San Pedro de Macorís, Dominican Republic
263 km (164 miles) W (259°) from San Juan, PR
. . . . . . . . . .

  Feel better now?

[sparrow]

Back on track

[thirtyhz]

   Geez....finally.

That session was, without a doubt, the creepiest thing I've witnessed in a long time.

But....you knew this was coming....I gotta know WHY. 

[shy]

I gotta know WHY. 

Currently USGS lists Puerto Rico week's worth of quakes as totalling 29.  I suspect it was just malfunction of eq recording equipment or something of that nature.  Breath easier now?

[thirtyhz]

As of last night, around 8pm EST...there were TWO quakes. 

As of this afternoon....there are 29.

I'm sticking to my guns.  Something is WAY off.

[Mizar]

Yes, Thirty, I noticed the same thing this morning, all of a sudden there are quakes reported in the Puerto Rico Area.
  Something is way off.
  For many years I have suspected that something is hidden undersea in Puerto Rico area that causes these quakes, perhaps something from a lost continent.
   Mizar

[shy]

When I looked before there were 29 USGS quakes listed (on list giving the lat. long, time, etc.)  with the dates spread  throughout the week--they didn't all just happen in one day. 

I just went back to check the list & it had been replaced with what seemed to be a very incomplete list of quakes for the last several months--last quake date listed: 3/6/2010--& the site that came up said it was the "Puerto Rico Seismic Network"  @   http://www.prsn.uprm.edu/English/index.php  and stated:
 
                           **this page is under construction** 
                           RECENT SIGNIFICANT EARTHQUAKES

Yes Puerto Rico may have significant potential problems but I still suspect something isn't right with their data collection/displaying equipment.

 
   

[thirtyhz]

We shall see.  Yes, there is more in the area than meets the eye, and it's been a watch point for me for quite some time.

shy, thanks for finding the quake data.  I guess the only way to know for certain is to be there.  But really...there could be data collection problems.

And that in itself would be a first in the years watching the area.