Earthquake in Boise???

[nowhereman427]

Originally Posted by Ruth4Truth

Interesting topic. Just happened to see the thread title on the board while passing by.

Born & raised Bay Area-ite, here. Also lived in Seattle for quite awhile. Grew up with minor earthquakes. Routine minor ones are good; they release the pressure building up along the fault lines. I missed the Loma Prieta quake in Oakland. 1989.

But I remember the quake in the Seattle area in 2001, a 6.8 one. I was at home in the one room that had a cement slab floor. It felt like the floor was twisting on an axis parallel to the ground. No buckling type of motion, just a few seconds of twisting. But I was on the phone with someone in a downtown office building, who was 18 floors up. The entire building was swaying, and she was freaking out, so I ended the call. The minor quakes I felt at home in Berkeley when growing up felt like a little momentary light shaking, nothing more.

So as you can see, OP, how it feels to be in an earthquake depends in part on where you're situated at the time. I've never been in one that had auditory phenomena, like a couple of the reports here. That sounds scary.

One thing that's little known about the famous 1906 quake in the Bay Area, the "San Francisco earthquake", is that it actually had two epicenters. One was offshore of Golden Gate park in a section of the San Andreas fault that passes under the ocean. The other one is said to have been centered on Santa Rosa in the north part of the Bay Area. Geology books of CA point out a historic picket fence on a property in Marin County that was split in two by the quake. It's been maintained over the years, so you can still see it today. One length of the fence is 21 feet apart from the other, as a result of the quake. It's on land that now is a state park, so it's accessible to the public.

Tomales Bay in Marin County is right on top of the fault, extending along part of its length, and was created by recurring earthquake action. On a map, it looks like a section of Marin County (the area that included Pt. Reyes National Seashore and park) is being torn away from the North American continent. Some geologists expect that over time, it will become an island.
https://www.tide-forecast.com/tidelo...ifornia.10.gif

http://2.bp.blogspot.com/-qWtwJMmz5N...AUSGSImage.jpg

(I hope posting some earthquake lore and history isn't considered hijacking. )

If you haven't already seen it, there is a tourist spot up in Marin Co. that shows a fence on the San Andreas Fault that was moved over. So you can see the difference from how many feet it shifted from the original fence to the part of the fence that moved. It's a very large gap.

[banjomike]

Idaho's earthquakes have differences.
the lower half of our state lies over the Great Basin batholith, like a cork floating in a big bucket of extremely hot mud, while the other half isn't. But that half is solidly connected to the eastern side of the same great rift that the St. Andreas fault is a part of.

Each is separated by a a huge underground wall of granite that forms our mountain ranges in Central Idaho, so each quakes differently at different times.

In addition, our entire state is highly volcanic. Over half of the most recent lava flows in our state are only around 3,000 years old. They were happening around the same time Moses was busy crossing the Red Sea.

And they are older than the ash volcanoes that last blew up; St. Helen's is only one of them. It's not very far away, but it's still in the same tectonic plate as Idaho's dormant volcanoes in NID.

It's as was said earlier; the population makes all the difference in the attention, even though the threat is the same.

It's greatly ironic that the same things that can destroy us are what makes Idaho so beautiful and our soil so rich and benevolent.

[Syringaloid]

Here is an explanation from the pros:

https://www.usgs.gov/observatories/y...-central-idaho