Thanks. Makes sense if the epicentre is below the 49th parallel (which I guess is where it'll probably be).
Looks like sea levels could rise by a good meter and a half at some instances 'round here.
Thats not how subduction zone events work. Its not an epicenter, the whole 1000 km slips roughly 35 m .... one side lifts and the other falls, so the areas that would get plastered in particular are Victoria, and all of the Oregon coast. the way to imagine it is a wave coming up to say 50 ft high (but say a thousand feet wide bringing an incredible amount of water in) engulfs everything for a 1000 km.
The average reoccurance fromt he last souorc i saw says an average of about 450-500 years, but as little as 300 and as much as 850 year. The last occured IIRM on Jan 28 1700, so we are now in the possible zone, but the longer between events the larger the event (like the more you stretch a rubber band, the the greater the tension when it releases ...)
I slept in Sunday am...
At around 7:30 am, my bed shook significantly. I thought my crazy dog tried to jump in bed with me (a 130 pound bullmastiff). I realized he wasn't in the room, and we just had an earthquake...
This is in the LA area. The quake was small (3.9), but centered almost directly below us. My bed moved quite a bit.
I've lived in California for over 10 years now, and thankfully, have not had to deal with a real quake yet.
Anyways, glad to hear everything is ok up there. Maybe something really positive comes of it if it makes the powers that be look a lot closer at safety issues regarding the pipelines.
Thats not how subduction zone events work. Its not an epicenter, the whole 1000 km slips roughly 35 m .... one side lifts and the other falls, so the areas that would get plastered in particular are Victoria, and all of the Oregon coast. the way to imagine it is a wave coming up to say 50 ft high (but say a thousand feet wide bringing an incredible amount of water in) engulfs everything for a 1000 km.
The average reoccurance fromt he last souorc i saw says an average of about 450-500 years, but as little as 300 and as much as 850 year. The last occured IIRM on Jan 28 1700, so we are now in the possible zone, but the longer between events the larger the event (like the more you stretch a rubber band, the the greater the tension when it releases ...)
Man, I need to read some wikis. thanks for the explanation!
From what I remember reading a while ago, isn't Richmond in a lot of danger in the case of a big earthquake (i.e. the hypothetical Cascadia one)? Something to do with the ground basically turning to liquid and a lot of stuff falling over.
From what I remember reading a while ago, isn't Richmond in a lot of danger in the case of a big earthquake (i.e. the hypothetical Cascadia one)? Something to do with the ground basically turning to liquid and a lot of stuff falling over.
I really think there is a silver lining behind this. Northern pipeline has just shown its major weakness. Something you can't prepare for. They plan on putting it through one the most active seismic zones in the world.
You realise that the Caucasus region is also a very active seismic zone, and also very oil-rich, with many oil and natural gas pipelines, and they have had little issues in earthquakes. It would be similar here were they to build the pipeline.
i like to think i'm a fairly smart person and i do have a decent understanding of geometry and plate tectonics but could someone with maybe a bit more knowledge answer this:
could all these minor (well some not very minor) but fairly remotely located earthquakes along the BC coast possibly be taking a little tension off the JDF and NA plates and slightly reducing the chance of a mega 9.0-10.0 earthquake hitting soon?
i like to think i'm a fairly smart person and i do have a decent understanding of geometry and plate tectonics but could someone with maybe a bit more knowledge answer this:
could all these minor (well some not very minor) but fairly remotely located earthquakes along the BC coast possibly be taking a little tension off the JDF and NA plates and slightly reducing the chance of a mega 9.0-10.0 earthquake hitting soon?
Thats not how subduction zone events work. Its not an epicenter, the whole 1000 km slips roughly 35 m .... one side lifts and the other falls, so the areas that would get plastered in particular are Victoria, and all of the Oregon coast. the way to imagine it is a wave coming up to say 50 ft high (but say a thousand feet wide bringing an incredible amount of water in) engulfs everything for a 1000 km.
The average reoccurance fromt he last souorc i saw says an average of about 450-500 years, but as little as 300 and as much as 850 year. The last occured IIRM on Jan 28 1700, so we are now in the possible zone, but the longer between events the larger the event (like the more you stretch a rubber band, the the greater the tension when it releases ...)
Pretty close! It's not common knowledge but the last huge one was Jan 26, 9PM, 1700.
i like to think i'm a fairly smart person and i do have a decent understanding of geometry and plate tectonics but could someone with maybe a bit more knowledge answer this:
could all these minor (well some not very minor) but fairly remotely located earthquakes along the BC coast possibly be taking a little tension off the JDF and NA plates and slightly reducing the chance of a mega 9.0-10.0 earthquake hitting soon?
or do i just sound like an idiot...
I'm guessing you meant geology and that was just a freudian slip.
In any case, yes, that is the prevailing theory right now. However, (and this is just me as an undergrad geog. student musing) I am wondering if these 3 big EQ's on the east frontier of the Ring of Fire are leading to something. Guatemala, Haida Gwaii, and Vancouver Island.
Plus there was that pretty large one in Burma just yesterday or today, but that is (from what I gather) not a ring of fire event.
i like to think i'm a fairly smart person and i do have a decent understanding of geometry and plate tectonics but could someone with maybe a bit more knowledge answer this:
could all these minor (well some not very minor) but fairly remotely located earthquakes along the BC coast possibly be taking a little tension off the JDF and NA plates and slightly reducing the chance of a mega 9.0-10.0 earthquake hitting soon?
or do i just sound like an idiot...
Japan has a lot of earthquakes...(fairly large ones) every year.
It didn't seem to have an effect of lowering the magnitude of the catastrophic one they had a year ago...
Japan has a lot of earthquakes...(fairly large ones) every year.
It didn't seem to have an effect of lowering the magnitude of the catastrophic one they had a year ago...
So it seems that it doesnt work that way...
You raise a good point, however IIRC the Pacific plate is moving to the east so ... well, this graphic will explain better than my words will.
So, both the North American plate and Pacific plate are moving west. Meanwhile, the Juan De Fuca plate (not shown on that map as it is relatively small) is jamming into and under the NA plate.
In Japan's case, the Eurasian plate and Pacific plate are ramming into each other, which is a huge reason Japan exists. On the whole, there is generally more action on that side of the pacific.
I am open to corrections, but such is my understandings.
i like to think i'm a fairly smart person and i do have a decent understanding of geometry and plate tectonics but could someone with maybe a bit more knowledge answer this:
could all these minor (well some not very minor) but fairly remotely located earthquakes along the BC coast possibly be taking a little tension off the JDF and NA plates and slightly reducing the chance of a mega 9.0-10.0 earthquake hitting soon?
or do i just sound like an idiot...
No they have no effect on the chance or potential strength of future earthquakes.
We also have no way of knowing the strength of a future subduction zone earthquake because we A) don't know the built up tension and B) even if we did, we cant predict how much of it would be released.
Yeah, looks like we'd get it a bit, but it seems as if the lower mainland, for the most part, has a lot blocking it to help protect it from anything catastrophic.
Aberdeen, Washington looks like it'd be about the worst place to be.
Something people often don't talk about is a under water landslide of the Fraser river delta out in the Georgia straight. It can slide at any point in time, however during a major earthquake the odds of it sliding go up astronomically. The tsunami produced would dwarf anything a subduction earthquake could produce, it could be up to a 100 meters in height depending on the volume of built up sediment that slides. The main force of the wave would be directed at the gulf islands and pretty much wipe them out, much of the force would reflect back across the straight of Georgia and still be in the 10's of meters in height by the time it reached Richmond, Vancouver, West Vancouver, North Vancouver. It would also travel up the Fraser River and threaten everyone probably as far as Hope depending on the initial size of the wave.
As far as the wave that would result from the subduction quake it would take over 2 hours to reach the lower mainland, but it could still be high enough to breach the dykes around Richmond and damage anything not behind one. If we are in a high tide or a low tide obviously makes a world of a difference.
I would not like to imagine a combination of a 9+ earthquake, a large tsunami and a underwater landslide of the Fraser delta, in this case Richmond would be in serious trouble along with all other sea level communities.
*keep in mind that a 9+ subducton earthquake is also strong enough to drop the ground level by a meter or two, something that is for what ever reason often not taken in to account when measuring tsunami risks. Two things happen, A) the actual plate drops, B) soft soil compacts and water gets squeezed out of it.
Last edited by 0123456789*: 11-13-2012 at 02:44 AM.
thanks for the explanation!
