Question to you smart people in this group re: Nepal earthquake

[SheilaT]

42. You make a good point.

There are fault lines in places lots of people don't realize that are there. We already know a pretty good amount about the fault lines in California, and every single time there's a significant earthquake there, the geologists learn about new fault lines.

Most people have no idea that there was a major earthquake in Charleston, SC, in 1886. Did a lot of damage, and if something similar were to occur today, because of the increase in population, would be far worse.

The 1964 Good Friday earthquake in Alaska. The shaking lasted for five full minutes. Think about it. Most of the time the shaking is 45 seconds or less. Five full minutes.

Then there's the New Madrid earthquakes of 1811-12. Four major ones between December 16, 1811 and February 7, 1812. They were felt as far away as Denver, CO. They made church bells ring in Washington DC and Boston, Mass. The book On Shaky Ground by John Nance has an excellent account of them, as well as of the Good Friday Earthquake.

It's possible that global warming is having a small effect on earthquakes, and we know that fracking has an influence. But the big quakes? The earth itself, plate tectonics, does it without any help from us humans.

Factoid: Alfred Wegener proposed a theory of continental drift in 1912, but couldn't figure out the mechanism for it, because we just didn't know about plate tectonics yet. In 1960 there was a major quake in Chile, the largest magnitude ever recorded, and that one lasted 10 minutes. Geologists who studied it, soon realized that Wegener was probably right, and they started figuring out what we now know as plate tectonics. When the Good Friday quake occurred four years later, a group of geologists and seismologists were having dinner in the Space Needle in Seattle. The quake in Alaska made the Space Needle stop revolving, and they all knew immediately that something important had happened. In the end, that Good Friday quake confirmed the theory of plate tectonics.

All that is in the Nance book.