Apr 28, 2009, 10:00 AM
Post #5 of 9
We were aware of the quake here in Cuernavaca yesterday, although we did not feel it. My wife noticed that the glass doors on our entertainment center were trembling. When we looked at it we noticed the reflections on the glass were jumping all over the place, but we didn't feel anything here, the house was not moving at all.
We didn't get any phone calls from our family in México City, and someone always calls us whenever anything unusual happens there, snow, a particularly cold spell, etc. My suegra's apartment was destroyed in the 1985 quake there. I was raised in California which has a lot of quakes, and I spent the last half of my life in Alaska which is the most seismically active state in The US, earthquakes are at least a weekly event up there, so earthquakes are not unusual or terrifying for me.
Many people do not understand how the Richter scale is set to measure the severity of earthquakes. Every number indicates a doubling of the severity. A rating of 5 is fairly severe, a rating of 5.1 indicates a doubling of the severity, 5.2 indicates a doubling of a 5.1 quake, etc.
The second most severe earthquake ever recorded was the 1964 “Good Friday” earthquake in Anchorage, Alaska. The tsunami caused by that quake traveled across The Gulf of Alaska, when it reached Canada it killed a few people there, it then traveled down the west coast, the last people killed by it were a couple of fishermen in their boat in the bay in Eureka, California. That tsunami was only about two feet high when it passed San Francisco.
The most severe earthquake ever recorded occurred in Chile a few decades earlier. The tsunami from that quake traveled across The Pacific Ocean and killed some people in Japan.
We were not in México City when the 1985 quake occurred, but we went there as soon as travel to the city was again allowed. The damage was horrendous. There were collapsed buildings with bodies inside them all over the city. There was a collapsed medical clinic just a few blocks from my suegras destroyed apartment. The 20 nurses that were working there and all the patients in the clinic were missing and their bodies were presumed to be buried under the rubble. That site was not cleaned up for a couple of years.
There were tent cities all over México City for about ten years or more. Every park, and park strip was full of tents for people that had lost their homes in the quake. There were still people living in tents there in 1997. The city government was having a hard time getting residents to vacate them.
Besides the obvious cheating on building specifications and standards, the typical masonry construction used in México is particularly vulnerable to earthquake damage. A rigid building, no matter how strong, will be the first to collapse during an earthquake. A flexible building, such as a wood framed house, or a building specifically engineered to flex during an earthquake is the most likely to survive.
All buildings will collapse if the quake is severe enough though. A good rule to follow is if a severe quake lasts uninterruptedly for one minute, get out of the building. If you are taking a shower on a freezing night, if you want to live, get the hell out.
Yesterdays quake was kind of a non-event at this distance from the epicenter.
"The supreme happiness of life is the conviction that we are loved" - Victor Hugo