urbanSTL

metzgda wrote:Anyone have any damage that has brick masonry construction? We have a rental house in the city that is brick masonry and I'm wondering if we can expect any new fractures in the brick or to the limestone foundation.

It is not out of the question that you could experience some damage from this earthquake in older masonry structures. It is highly unlikely though that it would be anything that would impact structural integrity unless the house already had structural issues. The only thing I would expect to see would be existing cracks in masonry or foundation walls get slightly wider or a bit of settlement in buildings that have existing settlement problems (probably not noticeable though). It really depends on your foundation and the type and condition of the soil on which it is bearing. Generally, the softer the soil, and more importantly, the more variable the soil conditions, the more likely you are to experience problems. The geological conditions of the surrounding area can magnify the earthquake's effects as well, as the PD article correctly pointed out.

Felt that one. 4.5? That's a pretty strong aftershock for 3 days after a 5.2 earthquake. Maybe McClellan is right.

I want to weigh in on the animal thing. I think that the animal reaction is real, but I don't buy the "sixth sense" thing. Earthquakes create sub-sonic noise that we cannot hear, but that many animals can. I think that it is reasonable that they may hear noises coming from the impending quake that are below our range of hearing, and are generated by vibration that we don't notice. While the Richter Scale may note these vibrations, they can't be directly correlated with animal freak-outs because nobody bothered to set up a controlled environment for the animals--all we have are cats hanging from curtains and confused people. Animals like elephants for example use sub-sonic calls that we can't hear to communicate over very long distances. Sub-sonic noise travels great distance with far less attenuation than sound with higher-frequency. I don't know for sure, but I would expect that the experiments that were done to test for an animal's ability to predict an imminent earthquake were not done using actual earthquakes and therefore are not really viable. In order to do an experiment right, you would have to keep a sample animal population in controlled experimental conditions under behavioral and physiological monitoring 24 hours a day, 7 days a week, until an earthquake happened. It is much easier to simulate a quake, BUT putting a dog in a fake 'n' quake room like they (used to?) have at the science center would only measure a dog's reaction to a shaking room, big deal. Only a real earthquake can generate the unfathomably deep noise to which I hypothesize the animals are actually reacting.

Yeah, it wasn't as strong or as long as the first aftershock, but I definitely felt it. It rattled some doors and windows and set the house to swayin'.



BM is right in that we don't yet understand the relationship between different fault lines, particularly the various extensions of the New Madrid fault. Does activity along one extension say anything about the rest of fault? Noone knows. Hell, we don't even really understand the New Madrid fault itself yet, and probably won't until there is a major quake that can be studied.

Cats were freakin out again last night. I officially believe that they trully do have this extra sense... They have never acted that way before until just prior the earthquake and now it seems just prior to aftershocks... I am considering myself lucky because I have 2 hilarious, cuddly disaster predictors living in my house...

^But I also know plenty of people whose cats and dogs paid no attention whatsoever to the earthquake, before, during, or after.

^ Just cause they can sense it doesn't mean they are necessarily going to freak out.

The Central Scrutinizer wrote:

jlblues wrote:^But I also know plenty of people whose cats and dogs paid no attention whatsoever to the earthquake, before, during, or after.

And on top of that, people tend to remember the hits and forget the misses.



As in "my dog started acting strangely 10 minutes befire the quake, and he's never done that before" when, in fact, he exhibited the exact same behavior 6 months earlier when there was no quake.

My cats started acting strangely within 24 hours before each quake and substantial aftershock in the last 4 days. And No, they have NEVER acted like this way before. Trust me, when a cat freaks out in the manner I just witnessed, it's pretty easy to determine whether or not the cat has behaved in this manner before.

There have been a number of aftershocks in the Bellmont and Mount Carmel areas.(map)(list) In just the last week:



4.2 2008/04/25 17:31:00 8 km ( 5 mi) NNE of Bellmont, IL

2.6 2008/04/24 11:44:24 7 km ( 5 mi) N of Bellmont, IL

2.1 2008/04/23 01:32:34 9 km ( 6 mi) NNE of Bellmont, IL

1.6 2008/04/22 08:01:00 8 km ( 5 mi) N of Bellmont, IL

2.2 2008/04/21 07:58:46 8 km ( 5 mi) NNE of Bellmont, IL

4.0 2008/04/21 05:38:29 12 km ( 7 mi) NW of Mount Carmel, IL

2.3 2008/04/20 10:34:26 6 km ( 4 mi) N of Bellmont, IL

1.3 2008/04/20 09:59:44 8 km ( 5 mi) NW of Mount Carmel, IL

1.0 2008/04/20 06:32:02 8 km ( 5 mi) WNW of Mount Carmel, IL

1.7 2008/04/20 05:31:42 8 km ( 5 mi) NNE of Bellmont, IL

2.8 2008/04/20 05:02:42 8 km ( 5 mi) WNW of Mount Carmel, IL

2.8 2008/04/19 16:55:17 6 km ( 4 mi) N of Bellmont, IL

1.7 2008/04/19 12:45:38 7 km ( 5 mi) N of Bellmont, IL

1.3 2008/04/19 09:46:44 8 km ( 5 mi) WNW of Mount Carmel, IL

2.7 2008/04/19 03:05:53 6 km ( 4 mi) NNE of Bellmont, IL

Mill204 wrote:4.2 2008/04/25 17:31:00 8 km ( 5 mi) NNE of Bellmont, IL

Err, is this a typo, or a prediction?

^ All times are listed as GMT.

USGS Site wrote:GMT stands for Greenwich Mean Time and is the time kept near the Prime Meridian. It is 5 hours ahead of Eastern Standard Time, and is also known as Universal Coordinated Time (UTC). For more information, visit the NEIC's time information website.

Ah, guess I could have clicked on the link, so 11:31? Didn't feel it.

^ Actualy, 12:31. Forgot about DST.



^^I don't think too many people felt it: I was the only one in my family who did. And the tremor's strength has since been revised downward to 3.7. Pretty weak.

http://www.skepdic.com/fullmoon.html

Misconceptions about such things as the moon's effect on tides have contributed to lunar mythology. Many people seem to think that since the moon affects the ocean's tides, it must be so powerful that it affects the human body as well. The lunar force is actually a very weak tidal force. A mother holding her child "will exert 12 million times as much tidal force on her child as the moon" (Kelly et al., 1996: 25). Astronomer George O. Abell claims that a mosquito would exert more gravitational pull on your arm than the moon would (Abell 1979). Despite these physical facts, there is still widespread belief that the moon can cause earthquakes.* It doesn't; nor does the sun, which exerts much less tidal force on the earth than the moon.