Moderate Quakes Striking Odd Places in USA...Coincidence Or Not? Let's Find Out.

ETA: Here's a list of pertinent sites

USGS current list of earthquakes for the world

Current earthquake map for the US

Closest IRIS seimso to the Virginia quake

MSN article on Virginia quake




There are multiple threads going right now about some pretty strange quake activity happening almost at the same time in different areas of the US. It is making it hard to follow really what (if anything) is happening.

Just thought it might be helpful for those of us interested in the science behind this to look more closely at the quakes in question to clarify that these are seperate events....or put forth theories as to why you might think they ARE related.

I realize there is a quake watch thread (one of my favorites here!)....but it can be hard to wade through posts discussing activity around the world, vs those happening just here in the States.

SO...the obvious ones of the past couple of days:

Current USGS list of quakes. Note Colorado and ofcourse Virginia:

MAP 5.9 2011/08/23 17:51:04 37.975 -77.969 1.0 VIRGINIA
MAP 2.8 2011/08/23 15:54:25 19.303 -155.262 35.2 ISLAND OF HAWAII, HAWAII
MAP 3.7 2011/08/23 15:34:25 59.074 -151.094 37.1 KENAI PENINSULA, ALASKA
MAP 4.8 2011/08/23 14:28:56 36.475 71.236 75.0 HINDU KUSH REGION, AFGHANISTAN
MAP 3.9 2011/08/23 14:11:13 37.032 -104.690 5.0 COLORADO
MAP 2.6 2011/08/23 12:03:56 37.055 -104.761 5.0 COLORADO
MAP 3.2 2011/08/23 11:34:56 67.968 -146.118 14.6 NORTHERN ALASKA
MAP 3.2 2011/08/23 09:37:58 37.099 -104.711 5.0 COLORADO
MAP 2.5 2011/08/23 09:32:22 37.248 -104.705 5.0 COLORADO
MAP 2.5 2011/08/23 09:07:35 32.229 -115.353 12.1 BAJA CALIFORNIA, MEXICO
MAP 3.8 2011/08/23 07:17:59 37.099 -104.610 4.8 COLORADO
MAP 3.2 2011/08/23 07:01:35 37.109 -104.550 5.0 COLORADO
MAP 3.5 2011/08/23 06:56:59 37.110 -104.722 5.0 COLORADO
MAP 4.8 2011/08/23 06:04:56 42.100 142.480 45.6 HOKKAIDO, JAPAN REGION
MAP 5.3 2011/08/23 05:46:19 37.070 -104.700 4.0 COLORADO

Details on the Virginia quake: (now a 5.9)

Magnitude 5.9
Date-Time Tuesday, August 23, 2011 at 17:51:03 UTC
Tuesday, August 23, 2011 at 01:51:03 PM at epicenter

Location 37.975°N, 77.969°W
Depth 1 km (~0.6 mile) (poorly constrained)
Region VIRGINIA
Distances 45 km (27 miles) E of Charlottesville, Virginia
55 km (34 miles) SW of Fredericksburg, Virginia
64 km (39 miles) NW of RICHMOND, Virginia
82 km (50 miles) NNE of Farmville, Virginia

Location Uncertainty horizontal +/- 10.9 km (6.8 miles); depth +/- 7.4 km (4.6 miles)
Parameters NST=390, Nph=390, Dmin=57.9 km, Rmss=1.17 sec, Gp= 47°,
M-type=regional moment magnitude (Mw), Version=6
Source Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)

Event ID usc0005ild

(Note it is only 1KM or .06 miles deep!!!)

Details on Colorado quake:

Magnitude 5.3
Date-Time Tuesday, August 23, 2011 at 05:46:19 UTC
Monday, August 22, 2011 at 11:46:19 PM at epicenter
Time of Earthquake in other Time Zones

Location 37.070°N, 104.700°W
Depth 4 km (2.5 miles)
Region COLORADO
Distances 15 km (9 miles) WSW of Trinidad, Colorado
33 km (20 miles) NW of Raton, New Mexico
54 km (33 miles) S of Walsenburg, Colorado
290 km (180 miles) S of DENVER, Colorado

Location Uncertainty horizontal +/- 12.5 km (7.8 miles); depth +/- 2.8 km (1.7 miles)
Parameters NST=372, Nph=372, Dmin=18.9 km, Rmss=1.25 sec, Gp= 14°,
M-type=centroid moment magnitude (Mw), Version=A
Source Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)

Event ID usc0005idz

Current map of the US from the USGS:



Source for all info and map

I just want to caution people that while at first glance it might seem like there is something BIG happening here in the state, this really most likely is just two seperate, unrelated events that when put together seem like something more sinister.

Let's try to keep any discussion on the level, without sensationalism.

Wow just saw all the EQ threads popping up all at the same time!!

What on Earth is happening right now? All these different locations at the same time - it's crazy.

I'm staying close to this thread

ATS is shutting down threads as fast as they are put up about the East Coast EQ

It is not the earthquakes in areas with faults or volcanoes that should be payed attention to, as there will always be earthquakes.

Rather it is the ones that are in what would be considered geologically stable areas that bear for us to pay attention to, as they are out of the ordinary and should be of concern. The 2 that the OP mentioned, the one in Colorado/New Mexico, and the one in Virgina, those are something that everyone should wake up and pay attention to, as there is no faults in that area, infact looking at the geological maps they do not make sense as to why they occured.

Originally posted by mikeybiznaz
ATS is shutting down threads as fast as they are put up about the East Coast EQ

No they aren't, the mods are consolidating them into 1 thread so the forum doesn't become unorganized chaos.

reply to post by westcoast


Thanks westcoast for the update and clarification. Always like your posts on EQ matters.

I've never seen so many threads and replies pop up like that.

One question is why was it felt in such far away places? Is it due to the shallow epicenter, or because of the lay of the land out east and no resistance to stop the wave?

Again, thanks for tossing in some rational thought. This really rattled some folks. (Can't blame them. I'd be a little edgy if a 5.9 hit Minnesota.)

The CO quake --- although not huge by fault-area standards --- was unique becuase it was so large based on history. Biggest in 40yrs. How about the VA quake? How does that one stack-up historically?

A little fearmongering

Someone said a Mw 6.0 quake didn't kill anyone (in another thread).
My question to that is: But what if it was a pre-quake?

The pre-earthquake to the large Mw8.9 earthquake was a Mw7.2Source

If so and it got same increase you might get a Mw7,5+ in "the real" quake.

Askeing because i dont believe the media, my question is how often do prequakes happen?

Imagine I'm not the only one who would like to know at moment.

7,5 is quite bad if you look at the Richterscale.

westcoast...when I saw this on the news I immediately thought of you. Thanks for your knowledge and time and effort you put in on ATS.

well wescoast i applaude your timming,,, lol
it was impecable,,
but being from cape breton ,, New Waterford area,,

is it going to split this far?
or can we see some atlantic, or hekla activity next?

reply to post by westcoast


well wescoast i applaude your timming,,, lol
it was impecable,,
but being from cape breton ,, New Waterford area,,

is it going to split this far?
or can we see some atlantic, or hekla activity next?

opps

reply to post by Drew99GT


in another 5 minutes I will have been called a fear monger....imagine that, my fear causing a 5.9 EQ in Virginia

ETA: Closest iris seismo for the colorado quake

Just reading through the responses....but before I respond to those I want to comment on the activity I am seeing right now on the east coast on a live seismic program called GEE.

There was another moderate quake just a few minutes ago in the same area, will update this when USGS posts it.

Originally posted by jtma508
The CO quake --- although not huge by fault-area standards --- was unique becuase it was so large based on history. Biggest in 40yrs. How about the VA quake? How does that one stack-up historically?

earthquake.usgs.gov...

It's about equal to the largest recorded EQ in Virginia history.

reply to post by Drew99GT


Thanks for your input (on both threads) with very good info!!!

Here is a screen-shot of what I am seeing. @TrueAmerican; if you are reading this, I am sure you'll appreciate what I am getting at)





The quake at the bottom is the station closes to the 5.9 in Virginia. The other quake on the one above it is the station closest to the 5.3 that happened in Colorado.

(ETA: To clarify, this screen-shot is realtime. The quakes you see on there happened about 15 minutes before this post)

So far...neither of these are listed on USGS, even for 1+ mag quakes. I am sure they are busy right now.

So CO has a shallow quake, largest in over 40yrs and within a day VA has the largest in 114yrs... also a shallow quake. Coincidence? Those are some HUGE odds.

reply to post by jtma508


YES...well said. Thank you. THIS is why I started this thread, because they could very well just be very odd, rare coincidences..........I NEVER like coincidences. Especially in the scientific world. It just kinda stinks right now and I am hoping its not rotten eggs I smell.

Originally posted by jtma508
So CO has a shallow quake, largest in over 40yrs and within a day VA has the largest in 114yrs... also a shallow quake. Coincidence? Those are some HUGE odds.

Anyone have any credible info on current planetary/celestial alignments/comet Elenin alignments???

So another, larger quake rolling across GEE right now. When I say large, I don't mean huge. Hard to tell just how big it is because I can only pull up the BHZ channel but I think it is at least a 3 or 4 mag.

There are rumours that USGS is being cautious about calling that 5.9 the main event....meaning it could be a foreshock to something bigger (like in the seven range). I think the same could be said for Colorado.

I am going to steal some info from my friend Puterman off the quakewatch thread. He determined that The Colorado quake and the Virginia quake fall on almost the EXACT same latitude!


37.975°N VA, 37.13°N Colorado


Also...now I just found they (USGS) finally updated the quake list to include the one on the screenshot:

Magnitude 2.8
Date-Time Tuesday, August 23, 2011 at 18:46:50 UTC
Tuesday, August 23, 2011 at 02:46:50 PM at epicenter

Location 37.931°N, 77.935°W
Depth 0.1 km (~0.1 mile) (poorly constrained)
Region VIRGINIA
Distances 9 km (5 miles) SSW (195°) from Mineral, VA
12 km (7 miles) SSE (151°) from Louisa, VA
28 km (18 miles) NE (45°) from Columbia, VA
60 km (38 miles) NW (316°) from Richmond, VA
136 km (84 miles) SW (217°) from Washington, DC

Location Uncertainty horizontal +/- 2.4 km (1.5 miles); depth +/- 5.3 km (3.3 miles)
Parameters NST= 10, Nph= 12, Dmin=53 km, Rmss=0.16 sec, Gp= 97°,
M-type=duration magnitude (Md), Version=A
Source Southeast U.S. Seismic Network

Event ID se082311b

This means the one I am looking at now is in the 3-4 range.

Originally posted by westcoast

I am going to steal some info from my friend Puterman off the quakewatch thread.

He determined that The Colorado quake and the Virginia quake fall on almost the EXACT same latitude!


37.975°N VA, 37.13°N Colorado

And the Virginia quake was at:

Location 37.931°N, 77.935°W

Oh boy, that's a little unsettling.