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Regulator Country said, "I was trying to be helpful, not everybody’s out there trying to embarrass someone else with a gotcha."

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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So — when comparing damage in Mexico to California, “different building codes” is probably the most workable explanation — for now... :-) ***

After RG posted about the use of tie rods in Charleston I read up more. Interesting stuff. Fire in early 1800’s burned the wood structures, but brick and stone homes from the 1700’s survived. New homes had to be built out of brick and stone per code (1800’s with building codes!).

EQ in late 1800’s destroyed newer brick and stone homes - 1700 homes still intact! Homes repaired or rebuilt in late 1800’s after EQ had to use tie-bars as per new city codes.

It got me thinking about codes and laws and stuff. They do serve a purpose in protecting the community as a whole. But when do they become so restrictive that they infringe on personal liberties? I was helping out a friend with getting a new water heater installed. The code calls for a pressure relief tank to keep the tank water from back-flowing into the city system. One plumber says that by code they have to be installed. Another plumber said it is a “grey area” and that it is only required at the time you sell the house. He was happy to install one, but also said that the rules may change by the time you sell - so it STILL may not be good enough.

I’m not so sure about the second plumber - I mean a “code” is code I would think. The only think is when you sell the home, someone will actually be looking to see if things are up to code.