It is time for the occasional blogger to once again poke his head into cyberspace. Seeing the various quakes which have been happening since the last post, about 4-1/2 months ago on Saturday, September 30, 2018, it is time to make a few comments.
On Tuesday, February 6, 2018, an M6.4 quake struck off the east coast of Taiwan. An image, linked here, shows one of the buildings in Taiwan which got tilted over a bit. A page, linked here, gives some information about this quake. Once again, this was a quake with a magnitude of only 6.4, which tipped this building at such and angle.
Linked here is another picture of that building in Taiwan, which is tilting greatly. Just think what it may have been like to be in that building. And again, that happened with only an M6.4 quake.
On Saturday, February 6, 2016, a different M6.4 struck Taiwan. This time the quake struck about 30 miles east of the city of Tainan, which has a population of about 2 million people. A picture, linked here, shows a couple of more buildings which tipped over, plus a lot of damage. A page, linked here, tells what happened. And, once again, all this happened with just an M6.4 quake.
Let's now look at what happened during the Great Tangshan Earthquake in China, on July 28, 1976. This quake had a magnitude of 7.8 and killed at least 242,000 people, which was the official claimed death toll (link), but other estimates have the death toll as high as 650,000 people (link). Accessed here, here, here, here, here, and here, are pictures of damage which occurred during this quake.
A 7.8 magnitude earthquake, when using the USGS earthquake comparison calculator, linked here, is found to be about 25 times bigger than the 6.4 magnitude quake, but it is almost 126 times stronger in the energy released. So, take another look at the pictures and see the difference in damage resulting from these two different sized quakes.
Now that we are looking at comparisons, there is something to consider. The quake which is expected in the Cascadia region of North America --- in the Pacific Northwest of the United States and the adjoining part of British Columbia, Canada --- may have a magnitude of 9.2 or potentially a bit more. So, it is time to take a look at something.
Using the USGS earthquake comparison calculator once again, a magnitude 9.2 quake is about 25 times bigger than a magnitude 7.8 quake, like that which struck Tangshan, China, in 1976. But, a 9.2 quake is about 126 times stronger in the energy released, compared to that released by a magnitude 7.8 quake.
It is time for a bit of Reality 101. Once again, take a good look at those pictures linked above, which compare the two different size quakes and the resulting damage.
Now, take those Tangshan pictures, from the M7.8 quake, and imagine in your mind devastation at a much greater scale, from a quake which is 25 times larger in ground motion and 126 times stronger in the energy released.
Now, consider that which appears to be in the future for the Cascadia region of North America. Have you started to prepare yourself for something like this? If you haven't yet, now is the time to start.
Yes, it is true that things can be different at different locations. There are many factors involved when it comes to how much damage will result at any given location. But nevertheless, a magnitude 9.2 or larger quake can potentially make quite a mess of things in the Cascadia region. So, now it the time to start preparing. Tomorrow...
For further reading:
Current Expectations for a Cascadia Mega-Quake
https://cascadian.neocities.org/cascadiaquake.htm
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