Also keep in mind, that due to the the logarithmic nature of the Richter Scale, tenths are really significant when you pass 7.0:
IOW, an increase from 7.0 to 7.5 is a greater increase than from 6.0 to 7.0...
Posted on 02/16/2018 3:57:12 PM PST by blueplum
Also keep in mind, that due to the the logarithmic nature of the Richter Scale, tenths are really significant when you pass 7.0:
IOW, an increase from 7.0 to 7.5 is a greater increase than from 6.0 to 7.0...
that’s what she said
ESL?
I think that is part of it.
I also think tectonic plate dynamics may play into it.
Is there something about their fault lines down there that cause movement to be more broadly felt?
In the western usa where we get most of our quakes that is the case due to the shallow bedrock (mountains). However, the Great Madrid shake near the Mississippi in Missouri knocked some brick chimneys down in Boston in the late 1800’s!
When that one goes again it will be bad for us, as not a lot of our infrastructure in the midwest or east was designed for large quakes. I think they have done a lot of work on upgraded bridges across the Mississippi - but oil and gas pipelines that supply the east will be hard hit.
The New Madrid quake(s) were in 1812. You might be confusing it with the Charleston, SC quake of 1886. They both had very widespread effects due to the nature of east coast geology compared to the west coast as you note, though.
“...tenths are really significant when you pass 7.0”
As one who’s middle name used to be “filthy” - I’m guessing the “that’s what she said” is in reference to 7 inches with regard to one’s manhood?
No - I was thinking of the 1812 events - so we are even MORE overdue for the next one than I thought! (I have no idea on what the “normal” cycle is for that area. Although I seem to recall that we might be close - it is on the order of hundreds of years and not thousands.
And a quick search comes up with “rang church bells in Boston and toppled chimneys in Canada” so I was wrong on that too I guess!?
Pretty difficult to prepare for something of that magnitude on a national level (retrofitting all the pipelines, bridges, tall buildings, etc.).
As a bit of a prepper type though - one CAN prepare individually for these disasters.
Both of them had very widespread effects due to east coast geology, nowhere did I imply that you were wrong about that. I also merely suggested that you were thinking of the Charleston quake because it actually occurred in the late 1800’s and caused damage in Boston, since the New Madrid quakes occurred in 1812.
Try not to be so sensitive. I was trying to be helpful, not everybody’s out there trying to embarrass someone else with a gotcha.
Yes, that’s a very good point, and a real good example of the differences in more local vs long distance damage.
There is a fault line that runs from Missouri up near Boston.
It rang church bells in Boston and made the Mississippi run backwards temporarily in at least one area, and changed the course of the river.
Sparsely populated regions in 1812 are now more densely populated. That’s the real kicker right there. That coupled with less earthquake required infrastructure could be two very bad omens.
Some earthquake retrofitting isn’t that costly or hard to do. It’s mostly cabling framing so that it is much less likely to collapse, and shoring up masonry, bricks, chimneys, and the like.
There are wrought iron “stars” all over the facades of older brick buildings in the Carolinas, that people assume are purely decorative, and they did design them to be decorative. But, the primary purpose served was to keep the brick walls from collapsing into the streets as they did in 1886 during the Charleston quake.
I was just teasing myself.
Of course I started looking at the New Madrid fault news, and while the past cycles have been about 500 years, new research may indicate that it is “shutting down”. But that is based on surface deformation in the area - which may not tell the entire story. Or - the action has just moved along the fault zone to another region that they aren't monitoring.
I saw some other sites in my google search that had predictions of the next New Madrid quake (ushering in the Apocalypse too). So I'm not sure what we need all of the scientists for!
I just saw a movie where the entire brick building was covered with something similar and I figured it was just for decoration. Of course I had to google it after your comment about the chimneys.
I couldn’t figure out how to copy the link, but the following came up on my search. Looks like an interesting college thesis:
Ties That Bind: The Emergence of Iron Tie Rod. Reinforcement in Load Bearing Masonry Buildings of Charleston, S.C.. Jamie Lynn Wiedman. Clemson University
In that thesis paper the guy focused on Charleston, but had examples of the Romans using iron tie rods from way back when!
https://www.youtube.com/watch?v=Dh2oeSwTGCY
7.2 Earthquake Hits Mexico - Terremoto en Mexico (COMPILATION)
This is all Trump’s fault. There are too many Mexicans in Mexico, because he doesn’t want them moving to California or Texas, so Mexico is tipping. If only he had let them cross the border, it would be California tipping, and it would serve them right for stealing the land from Mexico.
WOW! Prayers up for all the good people of this area.
Lol
Same here -- that's why, in discussing seismic "tele-effects", (effects at a distance) I posted the Richter Scale graph.
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When comparing tele-effects along different "propagation paths", (between different locations) it's imperative to use the same energy input (magnitude and waveform and depth) for both paths.
Comparing the distant effects of DoughtyOne's "I experienced four or five 6.5 to 7.0 (roughly) earthquakes in Southern California " with the New Madrid event is like comparing effects of McVeigh's truck bomb in OKC with one of our biggest thermonuclear devices!
Take a look back at the seismograms I posted in #32. None of the aftershocks would have even been detectable on those seismometers -- even if there hadn't been the 7.2 that "wiped out" the plots for several hours. A 6.0 at the same Mexican location would have had the same ~15 minute "travel time" delay, but would have barely produced a blip. A 7.0 would have produced a ~half-scale deflection on the other side of the Pacific...
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Because of the complexity of our earth's internal structure, this seismology stuff can get frustratingly complex, folks! Without mega-time on a supercomputer, I don't know of any way to compare distant effects of a 7.2 at 24.6 km depth -- in western Mexico -- with the same event at the New Madrid coordinates.
Well, I guess we could wish for a matching 7.2/24.6KM event at the New Madrid coordinates -- but, I'm sure none of us really want that to actually happen!!! :-|
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Bottom line: this seismology stuff is just too complex for intuitive guesswork.
However, largely because of mankind's interest in seismically prospecting for oil (and detecting nuclear tests) the seismology of our (relatively stable) earth is amazingly well calibrated (and modeled).
But seismologists are still very wary of making predictions...
OTOH, the same is definitely not true for our hyper-complex, unstable, and chaotically ever-changing atmosphere. That's why seismologists (among other real scientists) consider the models and predictions of Gorebull Wahruming to be anything but "settled science" (or real "science", for that matter...)
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So -- when comparing damage in Mexico to California, "different building codes" is probably the most workable explanation -- for now... :-)
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