Alaska Earthquakes 0131-0200 24 Jan 2016 Z+9

[GypsyComet]

A 7.1, or even a 5.1, is quite dangerous in areas that aren't built for it. Even if the various municipal Alaskan Building Departments aren't enforcing the UBC* according to the local seismic zone, and I suspect they are, Alaska has had a couple big quakes in living memory to remind them.

Absolutely believable, especially from that company. They have the "Silicon Valley Mindset" in spades.

And yet, most of the actual area of Silicon Valley is built no taller than ten-fifteen stories. The central office districts of cities like SF, NY, and similar enforce a mindset and real estate "sensibility" like nowhere else.

*-Universal Building Code: annoying for the builders, life-saving for the occupants

 

[maksimsmelchak]

Alaska had a bunch of earthquakes in half an hour...

Peak was reported as 7.1
there's also a 6.8, a 4.8, a 3.2, and 2x 2.8's last I checked.

I'm fine. This is the first one to knock things off shelves...
We had a good solid 3 minutes of shaking felt in Eagle River...
The 2.8's barely registered to us... but the cats noticed.

Hope you and your family are well and there has been no significant damage.

Shalom,
Maksim-Smelchak.

 

[Blue Ghost]

Absolutely believable, especially from that company. They have the "Silicon Valley Mindset" in spades.

sure. in the financial world what matters is how much you get paid next week. next month is like, dude, nowhere, and next year is like, dude, huh?

I was there last Friday to pay my bridge toll at the Fast Trac office (Golden Gate bridge got rid of toll takers), and I parked the next block over, and walked underneath it.

Get this, they're not only building it in San Francisco (the Bay Area's way overdue for it's "big one"), not only is it Sears Tower and larger proportions, but it's a block away from the Bay Bridge on ramp, and it's arched over 1st street. It's massive, and they don't even have the first floor done.

I will not be living in SF anytime soon.

*EDIT*
Downtown financial section at least.

p.s. with all the Superbowl stuff and construction and road repair, the place is an absolute zoo. Which is funny since the actual game is being played in the South Bay region an hour south, and now where near SF. Go figure.

 

[BlackBat242]

The AP story on the quake included this part:

Andrea Conter, 50, of Anchorage said she was surprised by the quake's strength.
"This was a wild one," said the former Southern California resident. "I looked at the closed-circuit cameras at work, and it lasted over 50 seconds, and that is considerable for an earthquake.
"When I bought my house in Anchorage, I had a geological map that shows what are the sturdiest parts of town, and there were a few where I said 'If there's an earthquake, that house is toast,'" Conter said.
"That's how I chose my house, literally. Drove my real estate agent nuts. But, I didn't have one thing fall in my house."

Sounds like she was tired of earthquake damage.

 

[aramis]

The AP story on the quake included this part:



Sounds like she was tired of earthquake damage.

Hey, I am tired of Earthquake Damage. And the only thing I had fall was a couple books!

Note that Downtown anchorage has 20-some faults... (on maps, downtown is generally 1st to 9th, Medfra to the water. "Old Anchorage" (the 1975 city limits: Boniface to the water, 1st to Northern Lights, then down Spenard Road to 15th, and 15th to the water.) has over 30.

The Anchorage bowl is a collection of microterrains acreted on the plate junction...

Here's the Muni's own seizmic stability map... note that the downtown area is the most likely to fail... (Elmendorf AFB is the northern 5th of the map, save for the colored chunk to the west, called Government Hill.)
https://www.muni.org/Departments/OCPD/Planning/Planning Maps/Anch_Bowl_Seismic_8x11.pdf
My home is east of this map.

 

[GypsyComet]

The Anchorage bowl is a collection of microterrains acreted on the plate junction...

Some of the bad zones on that map look like estuary mud locations, which is also one of the SF Bay Area's issues.

 

[aramis]

Some of the bad zones on that map look like estuary mud locations, which is also one of the SF Bay Area's issues.

They aren't. They're glacial silt mud base with plantlife above. Which is actually far worse than estuarine mud for liquefaction.

 

[Blue Ghost]

I seem to recall liquefaction being a primary factor for Anchorages big quake way back when.

 

[aramis]

I seem to recall liquefaction being a primary factor for Anchorages big quake way back when.

Yep. All the red zones dropped about 10'.

 

[Blue Ghost]

Wow. Just wow. Ten feet. That's quite a first step.

 

[aramis]

Wow. Just wow. Ten feet. That's quite a first step.

Parts of Valdez dropped 15... and then the Tsunami rolled in and swept half the city away. The current City of Valdez is not even on the same spot...

 

[Blue Ghost]

Not to scare anybody, but I've heard that Chicago, the Appalacians and a portion of New York are overdue for some kind of quake. If Tokyo, Anchorage and San Francisco seem bad, then you ain't seen nothing yet.

 

[Deldarius]

The Gilboa Dam, a little over an hour away WSW of Albany, NY will likely give way due to an earthquake. There has been quite a few problems with it over the past several years due to flooding. It will make a beautiful mess* when it does go.




*Not saying disasters are good, but the raw fury of mother nature is both amazing yet horrifying.

 

[pshrynk]

There's a fault zone in the Mississippi Valley called the New Madrid that let loose with a 6.8 quake in 1895. The Mississippi was flowing backwards in some areas from the shift in geography. Another of those "overdue" fault lines...

 

[G. Kashkanun Anderson]

There's a fault zone in the Mississippi Valley called the New Madrid that let loose with a 6.8 quake in 1895. The Mississippi was flowing backwards in some areas from the shift in geography. Another of those "overdue" fault lines...

The New Madrid quake was about 10 times the magnitude of a 6.8, and it happened back in December 1811. Which is a good thing, really; it would have been much more deadly if it had happened in 1895!

 

[pshrynk]

The New Madrid quake was about 10 times the magnitude of a 6.8, and it happened back in December 1811. Which is a good thing, really; it would have been much more deadly if it had happened in 1895!

Oh, okay. The website I went to to look it up said 1895. Maybe that was when the last quake was. So that would be a 7.8, then? I don't recall much of my earth science from way back...

 

[BlackBat242]

The New Madrid quake was about 10 times the magnitude of a 6.8, and it happened back in December 1811. Which is a good thing, really; it would have been much more deadly if it had happened in 1895!

There's a fault zone in the Mississippi Valley called the New Madrid that let loose with a 6.8 quake in 1895. The Mississippi was flowing backwards in some areas from the shift in geography. Another of those "overdue" fault lines...

Oh, okay. The website I went to to look it up said 1895. Maybe that was when the last quake was. So that would be a 7.8, then? I don't recall much of my earth science from way back...

1811–12 New Madrid earthquakes
1. December 16, 1811, 0815 UTC (2:15 a.m.); (M ~7.2 – 8.2) epicenter in northeast Arkansas; it caused only slight damage to man-made structures, mainly because of the sparse population in the epicentral area.
2. December 16, 1811, the Daylight Shock, 1415 UTC (8:15 a.m.); (M ~7.2 – 8.2) epicenter in northeast Arkansas.
3. January 23, 1812, 1500 UTC (9 a.m.); (M ~7.0 – 8.0) epicenter in the Missouri Bootheel.
4. February 7, 1812, 0945 UTC (4:45 a.m.); (M ~7.4 – 8.6) epicenter near New Madrid, Missouri. New Madrid was destroyed.

October 31, 1895, 6.6-magnitude, with an epicenter at Charleston, Missouri.