Breaking News: Vancouver earthquake?

[kapkomet]

Haven't seen a thing, but someone just said there was a big earthquake in Vancouver?

 

Weird thing is, a freind of mine is supposed to be there this week to buy a house. How weird is that?

[southsider2k5]

According to USGS there was a 6.1 at 5:37 local time.

 

http://earthquake.usgs.gov/eqcenter/recent...s/10/230_50.php

[Flash Tizzle]

No earthquake will take Obama off my television screen, it seems.

[Texsox]

No earthquake will take Obama off my television screen, it seems.

pfft, it's Canada for Christ sake . . .

[Steve9347]

pfft, it's Canada for Christ sake . . .

Hahahahaha.

[KipWellsFan]

Rogers says this is normal activity for the region and there's nothing to be alarmed about.

 

http://www.ctv.ca/servlet/ArticleNews/stor...?hub=TopStories

[Texsox]

http://www.ctv.ca/servlet/ArticleNews/stor...?hub=TopStories

When someone says stuff like this is normal and nothing to be alarmed about, I always wonder if they are 1,000 miles away, or right there. That always seems to change perspectives.

[kapkomet]

6.1 seems pretty strong to me, but what do I know?

 

Edit: oh, so it was way out to sea. Nevermind.

[Balta1701]

6.1 seems pretty strong to me, but what do I know?

For any area along a subduction zone...if you're having problems with a 6.1, it's probably a good idea to just move. The fault system offshore of the Pacific Coast of the US north of the San Andreas is the kind of fault that can produce the gargantuan magnitude 9+ events.

[ChiSox_Sonix]

For any area along a subduction zone...if you're having problems with a 6.1, it's probably a good idea to just move. The fault system offshore of the Pacific Coast of the US north of the San Andreas is the kind of fault that can produce the gargantuan magnitude 9+ events.

 

Isnt that the one that caused the Alaska 9.1 or whatever it was earlier in the 20th century?

[Balta1701]

Isnt that the one that caused the Alaska 9.1 or whatever it was earlier in the 20th century?

Not exactly...it sort of is the exact same type of fault, but it's 2 different plates subducting. The Juan de Fuca plate is subducting under NW USA, and the Pacific plate is subducting under Alaska. There is another San Andreas style strike slip fault that sits between the northern edge of the Cascadia subduction zone and the Aleutian/Alaskan subduction zone...it's just a lot less well known than the San Andreas. But those subduction zones...those are the ones that can produce the really, really big ones.

[NorthSideSox72]

Not exactly...it sort of is the exact same type of fault, but it's 2 different plates subducting. The Juan de Fuca plate is subducting under NW USA, and the Pacific plate is subducting under Alaska. There is another San Andreas style strike slip fault that sits between the northern edge of the Cascadia subduction zone and the Aleutian/Alaskan subduction zone...it's just a lot less well known than the San Andreas. But those subduction zones...those are the ones that can produce the really, really big ones.

Isn't New Madrid strike-slip? It produced an earthquake in the 8's, and a shallow one that produced major damage.

 

[Balta1701]

Isn't New Madrid strike-slip? It produced an earthquake in the 8's, and a shallow one that produced major damage.

The New Madrid system is a different beast than all of the ones on the west coast, in that it's an intra-plate system. To first order, you can think of the earth as a bunch of big slabs of rock that produce earthquakes when they slide next to each other or underneath each other. The New Madrid system doesn't fit in to that, because it sits right in the middle of one of those plates. It actually sits in an old, failed rift system that formed one of the several times that north America tried to rift apart and failed. That movement, combined with subsidence, glacial rebound, and various other factors has left stress built up in the crust in that area that still hasn't totally subsided.

 

That's important to understand, because unlike the San Andreas or the Cascadia faults, there's not just one type of fault in that region. It's a complex system of thrust, normal, and strike slip faults, all of which can shift around to produce events. A portion of the key zone that caused the major 1811 events seems to be a combination of both a thrust fault and a strike slip system that is split by the thrust fault.

 

If you look at the map here, the parts parallel to the mississippi are strike-slip zones, while the left handed crook in the seismic epicenters is a step-over where the fault turns in to a reverse/thrust fault (same basic meaning). Based on a little bit of reading, and based on descriptions of the ground moving upwards in 1811 and rerouting the river (Something that typically wouldn't be expected in a purely strike slip event) I'd say the thrust part of the fault is the one that drove the 1811 events.

 

[LosMediasBlancas]

I'm about 20 mins. from the San Andreas fault. When is 'the big one' gonna hit us?

 

[Balta1701]

I'm about 20 mins. from the San Andreas fault. When is 'the big one' gonna hit us?

Within the next 100 years almost certainly, within the next 50 years more than likely, with a good chance of one happening at any time.

[Flash Tizzle]

Within the next 100 years almost certainly, within the next 50 years more than likely, with a good chance of one happening at any time.

The more I've learned about the planet the more convinced I am we're overdue for everything. Watch Mega Disasters -- every event featured within the program is accompanied with a warning of "it's not a matter of if, but when." We're due for another Tunguska sized meteor. We're due for Yellowstone erupting. We're due for some mini ice age. We're due for some virulent strain of flu. I'm sure we're due for a Gamma Ray Burst as well. The list goes on.

 

[knightni]

The more I've learned about the planet the more convinced I am we're overdue for everything. Watch Mega Disasters -- every event featured within the program is accompanied with a warning of "it's not a matter of if, but when." We're due for another Tunguska sized meteor. We're due for Yellowstone erupting. We're due for some mini ice age. We're due for some virulent strain of flu. I'm sure we're due for a Gamma Ray Burst as well. The list goes on.

 

If it all happens on the same day, that'll just suck.

[Balta1701]

The more I've learned about the planet the more convinced I am we're overdue for everything. Watch Mega Disasters -- every event featured within the program is accompanied with a warning of "it's not a matter of if, but when." We're due for another Tunguska sized meteor. We're due for Yellowstone erupting. We're due for some mini ice age. We're due for some virulent strain of flu. I'm sure we're due for a Gamma Ray Burst as well. The list goes on.

Part of the issue there is that some of those events aren't exactly well clocked, and we really don't have a full accounting of everything that drives them. Yes, we're due for another Tunguska style event...possibly. That depends on how many of those things there are in the area of the earth at a given time and other recent astronomical events that can change orbits. And it depends on their composition, because certain types of impactors behave differently in the atmosphere. And it depends on whether or not it hits land or the ocean when it does happen...the Pacific is pretty big and no one really cares if a comet explodes over it, if it isn't big enough to be tsunamigenic.

 

A mini ice age? Well, um, I don't think you have to worry about that. Even in the last 10,000 years, humanity got really, really good at keeping a stable climate, because every time we drove a small climate shift, a lot of humans died out. And now, well, there won't be any ice ages happening any time soon with what we've done to this atmosphere.

 

On Yellowstone...yes, the last 2 eruptions were 600,000 years apart, but the 2 before that were 900,000 years apart. We don't fully understand the dynamics of how a system like that builds to a large scale eruption or what the triggers are, and in fact, Yellowstone is doing some interesting stuff right now with all the hydrothermal activity (it's been at a highly elevated level for the last 100,000 years or so), which can cool magma more quickly and possibly delay an eruption. If you want a better answer on that then you need to help make sure the USGS funds my postdoc.

[Balta1701]

If it all happens on the same day, that'll just suck.

I think that's the short definition of the End Permian event.