YELLOWSTONE PARK DANGER

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As long as they're bubbling and venting, they're relieving pressure. I think if they stop, or aren't venting, those are the dangerous ones...

The concern is if there is a rapid movement upwards of magma, the (water) saturated ground could flash to steam pretty much all at once which would be a multi-gigaton equivalent explosion. That's what builds large calderas.

The geysers, hot springs and mud pots are from water seeping down to the heat; theoretically magma could very slowly creep toward the surface and dry out the rock but more likely it either stays where it is and gradually cools off, or a new path to the surface is used (probably because of plate motion over the hot spot*) and the magma comes up again and flashes.

*: the hot spot pretty much stays put while the crust floats by over it (numbers are millions of years ago where the crust was over the hot spot):

 

[big bubba]

interesting topic. along with volcanology comes it's cousin: seismic events. hard to say which is more predictable given today's tech.
i live in proximity of New Madrid fault, another catastrophic prediction that occurred previously along that fault line..

 

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interesting topic. along with volcanology comes it's cousin: seismic events. hard to say which is more predictable given today's tech.
i live in proximity of New Madrid fault, another catastrophic prediction that occurred previously along that fault line..

yeah that one's going to surprise the %$#@!^ out of a lot of people when it goes

 

[gstrom99]

interesting topic. along with volcanology comes it's cousin: seismic events. hard to say which is more predictable given today's tech.
i live in proximity of New Madrid fault, another catastrophic prediction that occurred previously along that fault line..

There was "an event" a few years ago along the New Madrid fault line in southern Illinois, that we felt up near Chicago. I thought "wow, that's cool", but when the news reported it most people there were like, "what's a New Madrid?".

 

[California]

There was "an event" a few years ago along the New Madrid fault line in southern Illinois, that we felt up near Chicago. I thought "wow, that's cool", but when the news reported it most people there were like, "what's a New Madrid?".

Wow. We've heard of New Madrid all the way out here in California. I suppose because everybody has earthquakes in the back of their mind here, so any mention anywhere is remembered.

I was in a third floor office in Sacramento when San Francisco's 1989 Loma Prieta earthquake occurred. Even 90 miles away, we got a shaking so severe and unusual that my first thought was 'Is San Francisco still there?' Soon the news showed that the distance between San Francisco and Oakland momentarily became great enough that the Bay Bridge separated at a 12inch expansion joint, and dropped one panel. Lots more similar damage.

 

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Wow. We've heard of New Madrid all the way out here in California. I suppose because everybody has earthquakes in the back of their mind here, so any mention anywhere is remembered.

I was in a third floor office in Sacramento when San Francisco's 1989 Loma Prieta earthquake occurred. Even 90 miles away, we got a shaking so severe and unusual that my first thought was 'Is San Francisco still there?' Soon the news showed that the distance between San Francisco and Oakland momentarily became great enough that the Bay Bridge separated at a 12inch expansion joint, and dropped one panel. Lots more similar damage.

I was less than 10 miles from the epicenter at a doctor's office - though I'd destroyed my left ankle the previous week (major blowout, bad sprain), I was there with a friend who'd rolled his car the previous night (!); and let's just say I have a reflex of jumping up when the slightest tremor occurs... so I kinda re-sprained my sprained ankle when that 6.9 hit.

I remember seeing the large fish tank in the dr office pretty much explode, fish all over the floor, I looked around and saw two doors - the one I'd come in to the office lead back to an indoor courtyard with an upper level walkway, definitely not a good spot to be in, so I went to the inner office door and took shelter there. Nurse came running out in a panic and I put my arm across the door and said "you don't want to go that way, stay here". When the shaking stopped a minute later I asked if there was a back door, and we went out that way and it was a lovely flat open blacktop parking lot - perfection, nothing to fall on us!

Every time there was an aftershock (like every few minutes) you got to see the ground wave ripple through the parking lot and watch as it flexed the buildings in a wave via their reflective windows.

I lived right nearby (water heater pipes let go and I remember soy sauce and spices all over the counters and floor). We slept in the backyard for a week because I find that the house walls do funky things to the air pressure which mess with my balance during a quake; outside you do feel it but it's nothing like being inside.

That was only a 6.9.

Even 90 miles away, we got a shaking so severe

(@California I know you know this already) Sacramento is also on mushy floodplain sediment so I'm not surprised (similar to where the greatest damage from the quake was in the SF Marina district - filled area - and also mushy areas in Oakland where a double-decker freeway collapsed). Relatively little damage occurred much closer to the epicenter; a couple hundred-year-old brick walls collapsed (one death in Santa Cruz if I recall) and some structural damage to a freeway overpass though no collapse.

 

[big bubba]

the original New Madrid quake of 1811-12 briefly changed the course of the Mississippi river. no telling what havoc would play out with Memphis not far away.

 

[California]

We slept in the backyard for a week because I find that the house walls do funky things to the air pressure which mess with my balance during a quake

That makes sense, we would too after that experience.

Family legend said Dad's older brother was likely conceived in a tent cabin in Golden Gate Park, emergency housing, a few days after the Big One - the San Francisco 1906 earthquake that levelled then burned down most all of the city.

 

[ning]

That makes sense, we would too after that experience.

Family legend said Dad's older brother was likely conceived in a tent cabin in Golden Gate Park, emergency housing, a few days after the Big One - the San Francisco 1906 earthquake that levelled then burned down most all of the city.

wait a minute... nope, my wife was already pregnant with #1 before the quake hit

 

[Mike0616]

the original New Madrid quake of 1811-12 briefly changed the course of the Mississippi river. no telling what havoc would play out with Memphis not far away.

Was told in history in school that the Mississippi River and Ohio River flowed BACKWARDS for a while after that quake hit.