Recent Earthquake Activity

[Arkarayne]

Here I am watching the playoffs, glance over and see:

4:28pm
Moderate to light Shaking reported in Northern California and Southern Oregon.

<broken link removed>

not a big one, but enough curiousity to make me look it up.

Location puts it a couple hundred miles off the coast, west-wise of Eugene.

Irony was I had just been discussing with someone the natural threats to the valley, floods and Earthquakes.

if you wanna make a question out of it, anyone feel it? and whats a good way to prepare for one, besides taking the bowling ball off the bookshelf.

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[bmgm37]

Didnt feel anything here.....

 

[TAT2D]

and whats a good way to prepare for one, besides taking the bowling ball off the bookshelf.

When the one rumbled through Beaverton several years ago (was centered up in southern WA, I think, everyone evacuated the building. Later we were asking security "Why didn't the evac alarm go off?" Answer is because YOU"RE NOT SUPPOSED TO EVACUATE during an earthquake. Most injuries come from folks being hit by bits of the building facade falling off, as they go out the door.

Either stand in a doorway, or in our case, dive under your cubie desktops.

MrB

 

[MarkSBG]

You are likely referring to the 2001 Nisqually quake.

Correct! Do not evacuate DURING an earthquake:

If you are indoors during an earthquake, keep calm and take cover under a heavy table or desk. Stay away from glass, windows or anything that could fall, like a bookcase.

If you are outdoors, move away from buildings, street lights and utility wires.

If you are in a crowded public place, do NOT rush for the doors. Everyone will be doing that. Instead, take cover under something heavy and stay away from things that could fall on you. Stay calm. Do not get in an elevator during an earthquake!

After an earthquake, be prepared for after shocks. After shocks are follow-up earthquakes that are usually smaller than the first one. They are dangerous because they can cause things that are weakened in the first earthquake to fall down.

If you are home and you smell gas or hear a hissing or blowing sound, open a window and get out of the building right away. It may mean that a gas line in your house has been broken. Tell your parent or another adult.

Buildings should be evacuated AFTER an earthquake though. Structures weakened during the initial earthquake could collapse during a aftershock.

 

[Arkarayne]

If you are in a crowded public place, do NOT rush for the doors. Everyone will be doing that..

It's kinda sad but true. Most people probably don't know it, so I guess it's understandable, trying to get to "safety", but who says the street's any safer ya?

 

[TAT2D]

Moderate to light Shaking reported in Northern California and Southern Oregon.

Wife has an aunt in Eureka. Said to ask her about the 'damage report' when I get home, so apparently there was some, there.

You are likely referring to the 2001 Nisqually quake.

Quite likely. Knew it'd been at least 5 years, but going on 10 already? Man... (Hey, where'd all my hair go?)

Also, wife had a friend that worked in S.F.'s Transamerica building when the big one hit there several years ago. Was in an after-work exercise class on the 4th floor and said the building was moving so much she couldn't even crawl across the floor. If she hadn't been in that class, she'd likely have been on the Alameda freeway about the time it pancaked.

MrB

 

[TAT2D]

Also, just ran across this thread.

http://www.northwestfirearms.com/forum/showthread.php?t=15797

[The 'similar threads' feature at the bottom of the page is pretty neat...]

MrB

 

[roguebowhunter]

was headed to albany in '89 was gonna go the scenic route up hwy 101... got a little late and decided to just take I-5 instead.... glad we did .. don't know where whe would have been .. BUT i thank god we changed our minds .. Don

 

[jimwsea]

I think there are times to evacuate, but the plan should be made ahead of time. during the February, 2001 Nisqually quake, there were some old, unreinforced masonry and wooden buildings in the Duwamish industrial district south of downtown Seattle that sustained major damage.

If I started working in one of these buildings, one of the first things I would do is scope out where I could quickly run to in case of an earthquake where I would have less of a chance of something falling on me. I prefer not to have to be in a building like that on a daily basis where it could come down on you like...a pile of bricks. If i could make it out the door, I'd rather stand in the middle of First Avenue South. The Duwamish area is a filled in mudflat.

BTW, I was working on the top floor of the Maritime Building (masonry and huge wood beams, but better reinforced) on Western Avenue when the Nisqually quake started. The building is basically on the mudflat of Elliot bay. I had already planned I would never make it down the stairs, so staying put was the best plan. It first sounded like someone was pounding on the ceiling for 5 seconds, then the building started to shake. I was the one to gather up the other two in the office and plant them in the doorway.

I could look out the window and see the lamp posts swaying at least 30 degrees in each direction (I remembered from physics class that steel has high elasticity)! With every shake, one book was spit off the east facing bookcase, but not from any of the others. A four-drawer steel file cabinet hopped with each shake, turning 90 degrees, then falling on its side (to the east).

Afterward, I noted the sidewalk around the whole building sank almost a foot (liquefaction) and the downspouts were all hanging at the bottom. I went home to West Seattle to check on the house which sits on something a little more solid - 300 feet of sand. I had one coffee cup fall off a shelf.

 

[MarkSBG]

I could look out the window and see the lamp posts swaying at least 30 degrees in each direction (I remembered from physics class that steel has high elasticity)!

Yup, steel is very high, about 29,000,000 psi with aluminum at about 10,300,000 psi and timber 1,600,000 psi.

Afterward, I noted the sidewalk around the whole building sank almost a foot (liquefaction) and the downspouts were all hanging at the bottom. I went home to West Seattle to check on the house which sits on something a little more solid - 300 feet of sand. I had one coffee cup fall off a shelf.

It is pretty unlikely that the settlement of the building was due to liquefaction. I would guess that the settlement you saw was partially caused by a vertical movement in the surrounding soil, horizontal shifting of soil, and localized compression of the soil under the foundation. Liquefaction only occurs in very deep sandy soils that are saturated (fully filled with water). It can be very dramatic as seen in Japan in 1964:

Deep clay amplifies the seismic movements and that was part of the reason why you saw such large forces.

The sand under your house is much more succeptable to liquefaction, but only if it is fully saturated with water during the earthquake. Houses historically perform very well in seismic events. This is because they are very light compared to other buildings and wood framing dissipates seismic energy very well...

 

[TAT2D]

Moderate to light Shaking reported in Northern California and Southern Oregon.

Wife has an aunt in Eureka. Said to ask her about the 'damage report' when I get home, so apparently there was some, there.

Got the report on this last shaker. Aunt lives right on the canal in Eureka, but I don't know if it's reclaimed land or not.

Said 'all the cupboards were dumped on the floor and an antique hutch was dumped over. Lots of broken glass there.

Also, interesting to me, she said *every* door in the house was open. I gather the place swayed enough to unlatch the doors?

MrB

 

[Arkarayne]

2 Days later: (I know it's not near us, but still important)

A 7.0 just hit off the coast of Haiti, near Port au Prince
with 5.9 and 5.5 aftershocks.

 

[whatzhizname]

2 Days later: (I know it's not near us, but still important)

A 7.0 just hit off the coast of Haiti, near Port au Prince
with 5.9 and 5.5 aftershocks.

Scary. If you're a person of faith, please say a prayer for these folks. This WILL be devastating.

 

[Arkarayne]

Reports are gonna be unconfirmed for a while, but projected devestation is going into the "Total" category.

 

[Gunner3456]

Prayers up. Those people already don't have anything.

 

[Trlsmn]

Haiti has averaged a 5+ quake every 15 mins since 2:00 PM pst this afternoon and it's still on going.




In brighter news, with the recent shake up housing has leveled off.....................

 

[jimwsea]

The sidewalk settled downward with respect to the building...not the building itself. The building, I was told, was built on pilings into the stiffer clay, but the surrounding sidewalk was not (and on unconsolidated fill).

Also, my house had a deeper basement than surrounding houses, and a squarish "Cape Cod Box" shape, so likely had less of a chance of generating different harmonics upstairs (my next door neighbor was in his back yard and saw the rolling waves), which may be a reason for no significant damage. There was lots of chimney damage in the area.

 

[Gunner3456]

Haiti is totaled. The property devastation and death toll will be incomprehensible. It's maybe the world's worst in 100 years. They were already the poorest of the poor. All seven hospitals in the capital city are leveled.

While we can't personally do anything more than perhaps donate to a service which is helping them and say prayers for them, we can certainly learn from it.

There is no clean water (totally polluted) or food. There are no medicines. The roads are ruined. There is no shelter. There will be no clean water or sewer system or electricity... nothing for the foreseeable future.

While my heart breaks for them, it is a laboratory to learn from.

 

[Arkarayne]

Well, with any luck, deaths won't exceed the christmas tsunami a few years ago in the indian ocean (over 200,000 dead or missing)

they are saying over 3 million have been effected by it, and over 30 aftershocks now staying above 4.0

 

[Gunner3456]

Well, with any luck, deaths won't exceed the christmas tsunami a few years ago in the indian ocean (over 200,000 dead or missing)

they are saying over 3 million have been effected by it, and over 30 aftershocks now staying above 4.0

That was horrible. The earthquake itself was off shore and the damage was limited to the coastline. The death toll was terrible.

In the case of Haiti right now, the earthquake is on the land, and the property damage is almost complete. The whole infrastructure is destroyed, not just the coastline. They are also already completely impoverished and they don't even have machinery to free trapped survivors. In the Indian Ocean tsunami, the death toll affected 14 countries, all the way to Thailand, and there was equipment inland to rush to the scenes. It was also easier to bring help because it was limited to the coastline.

I'm not minimizing what happened before, but this total destruction of a country is terrible. Not only are the poorly made buildings flattened or rendered useless, but all of the other infrastructure is affected.

I don't mean to sound heartless because my heart goes out to them and I sent a donation, but believe me I'm going to school on this one. This is a worst case SHTF. The people have nothing.