Landslide Nightmares

[hutash]

The California coast in general has issues. I grew up in a town near LA on the coast that had large parts sliding (with homes) in to the ocean pretty regularly. And going to college up in Arcata, Humboldt County was regularly cut off for weeks by landslides on US 101 and CA 299, leaving the only highway out through Oregon.

Yeah, because there is only 1,000+ miles of coast line. You never see this problem on the Nebraska coast

[Meadow Skipper]

Yeah, because there is only 1,000+ miles of coast line. You never see this problem on the Nebraska coast

I don't understand your point. I was responding to the post about the Big Sur landslide - there are a lot of landslides in the CA coastal areas. Are there a lot in Nebraska? WTF are you talking about?

[KQ]

We should be hearing the Donald offering his condolences and help any day now.

Yeah, was wondering where that was myself.

[garyfromterrace]

Anyone familiar with the Frank slide? Now that was a slide!

The Frank Slide was a rockslide that buried part of the mining town of Frank, Northwest Territories,[nb 1] Canada at 4:10 am on April 29, 1903. Over 82 million tonnes (90 million tons) of limestone rock slid down Turtle Mountain within 100 seconds, obliterating the eastern edge of Frank, the Canadian Pacific Railway line and the coal mine. It was one of the largest landslides in Canadian history and remains the deadliest, as between 70 and 90 of the town's residents were killed, most of whom remain buried in the rubble. Multiple factors led to the slide: Turtle Mountain's formation left it in a constant state of instability. Coal mining operations may have weakened the mountain's internal structure, as did a wet winter and cold snap on the night of the disaster.

Correction: not Northwest Territory, Frank is in Alberta. About an hour west of the amazing skiing of Castle Mountain.

[MagnificentUnicorn]

Anyone ever checked out the Hope Slide in BC? https://en.wikipedia.org/wiki/Hope_Slide

[neufox47]

Yeah, because there is only 1,000+ miles of coast line. You never see this problem on the Nebraska coast

Nor Florida.

[evdog]

Correction: not Northwest Territory, Frank is in Alberta. About an hour west of the amazing skiing of Castle Mountain.

Alberta didn't become a province until 1905. Prior to that it was a district that was part of the NW Territories.

And yeah, Frank slide is a cool spot. I remember reading about a house that was carried away intact by the rock slide, with a baby in a crib inside the house unharmed.

[KQ]

Nor Florida.

Yeah, Florida just has giant sink holes that swallow you up in your sleep,

[sb]

and love bugs

[plugboots]

Alberta didn't become a province until 1905. Prior to that it was a district that was part of the NW Territories.

And yeah, Frank slide is a cool spot. I remember reading about a house that was carried away intact by the rock slide, with a baby in a crib inside the house unharmed.

Ahhhh, now that makes sense. I’ve driven through Frank slide, but knew it was in Alberta, and just thought the great white North is pretty fucking big, there must be a lot of slides. Maybe a lot of Franks, too.

Inslee was on TV the other day saying the Union Gap slide was different than Oso because UG was “rock, solid rock”, and Oso wasn’t.
What in the actual fuck?

[Dantheman]

The California coast in general has issues.

In most places, the western slope of the California coast mountains is steep and largely composed of churned up sedimentary rocks that were scraped off the ocean floor as the Pacific plate subducted under the North American Plate. That makes for generally unstable geology.

The Thistle Slide is pretty famous in the world of landside geology. It was a slow-moving slide, but destroyed the town of Thistle, dammed the Spanish Fork River creating a 3-mile long, 200-foot deep lake, and closed two major highways for 8 months and a major rail line for 3 months. Direct and indirect costs were estimated around $1 billion (2018 dollars)

https://en.wikipedia.org/wiki/Thistle,_Utah#Landslide

Note the new cuts for the highway and rail-re-routes on lower-left. Massive earthmoving effort.

[bagtagley]

Is that the one you see on the way to Moab from SLC?

Edit: Just looked at the Wiki link. That's gotta be it. I'd always wanted to research that, but never remembered once I got home. It's knew it must have been a big one, but didn't realize it did that much damage.

[Norseman]

Inslee was on TV the other day saying the Union Gap slide was different than Oso because UG was “rock, solid rock”, and Oso wasn’t.
What in the actual fuck?

That's pretty fucking stupid.

Edit:

So is this the general landslide thread, now? So fascinating.

I'm fond of the Quake Lake area of SW Montana. Magnitude 7.3-7.5 quake in 1959, tied with San Fran for the second strongest in North America after the great Alaska quake.

50 million ranges of material 😁 broke off the mountain and blocked the Madison river, forming the lake that still exists. Being out in the lake is eerie, since many trees are still standing with their tops just above (or just below) the lake surface. Good backcountry skiing, whitewater boating, hiking, etc in the area. Lots of griz, too. The lake level is slowly dropping as the river cuts through the debris.

[KQ]

That's pretty fucking stupid.

Maybe he's speaking to this:



The Columbia Plateau, also known as the Columbia Basalt Plain, is the prominent geographic feature of the interior Columbia River Basin. The plateau formed between 6 million and 16 million years ago as the result of successive flows of basalt. Its northern border is marked by the Columbia River and the mouth of the Okanagon River. On the south, the plain includes the drainage of the Deschutes River in Oregon. On the east the plateau includes the Camas Prairie of central Idaho, and on the west it runs to the foothills of the Cascade Mountains. The Columbia River makes a looping S-curve through the central Washington part of the Columbia Plateau.

In a river basin that is mostly mountains and steep valleys, the Columbia Plateau is an area of flat land and gently rolling hills cut by the sometimes steep river canyons of the Columbia and its tributaries. It is a roughly triangular-shaped area about 250 miles on a side. On its fringes the elevation of the plateau is about 4,000 feet (1,219 meters) above sea level, and at its lowest point it is about 400 feet (122 meters). The Columbia Plateau is the major agricultural region of the interior Columbia River Basin and includes the cities of Ellensburg, Wenatchee, Yakima, Moses Lake, Walla Walla, Pullman, and the Tri-Cities of Washington (Pasco, Kennewick, Richland); Pendleton, Umatilla, and The Dalles, Oregon; and Moscow and Lewiston, Idaho.

The journals of Lewis and Clark briefly note the Plateau. On Sept. 18, 1805, Clark wrote: “...from the top of a high part of the mountains…I had a view of an emence Plain and leavel country to the SW. & West.” After their difficult crossing of the Bitterroot Mountains, the sight of the plain “greatly relieved the spirits of the party,” he wrote in the journals for the next day.

[abraham]

For more landslide nerdery check out the landslide blog https://blogs.agu.org/landslideblog/

There's a post about rattlesnake ridge https://blogs.agu.org/landslideblog/...snake-ridge-1/

[Norseman]

Excellent. Thanks Abe

[plugboots]

Maybe he's speaking to this:

Without a doubt, the make up of the underlying strata is different in the two areas. Duh. He should have left it at that, and moved on.

[Dantheman]

Is that the one you see on the way to Moab from SLC?

Yeah, just north of the US-6/US-89 junction on your way up Soldier Summit.

In the grand scheme of things, the largest landslides in modern history are nothing.

The Mt. Shasta megaslide is insane. See the bumpy hills in the photo below? All landslide debris that traveled as far as 30 miles.


Topo. Blocks of slide debris are yellow. Contour lines on the blocks are 50 meters



There have been huge landslides in the Hawaiian Islands that would have created massive tsunamis. All volcanic islands do this. Tsunamis this size could cause Lituya Bay-level destruction (http://www.drgeorgepc.com/Tsunami1958LituyaB.html) along the entire coast of a continent. 2004 SE Asian or 2011 Japan tsunamis would pale in comparison.

[plugboots]

Thanks Dan, great reading.

[XXX-er]

The "Hope" slide in BC was a big one, you can drive thru it on hwy 3 headed to Penticton. You can see where the MTN let go on lookers left , swept across the valley and right up the the other side on lookers right but it was only 41 million tons whereas the Frank was 78million

[LightRanger]

Here's a smaller manmade one:
https://en.wikipedia.org/wiki/Aberfan

So tragic.

[iceman]

Gonna be a lot to talk about in this thread in the near future when this shit goes off: https://www.newyorker.com/magazine/2...really-big-one

wtf are you people doing, living there? Shit is overfuckindue. And it's gonna be grim.

It's like if we on the East Coast had 300 years to get out of the way of a massive hurricane and we decided we're fine with it, we're staying right the fuck here. But we're not really gonna prepare at all. What?

[muted]

Gonna be a lot to talk about in this thread in the near future when this shit goes off: https://www.newyorker.com/magazine/2...really-big-one

wtf are you people doing, living there? Shit is overfuckindue. And it's gonna be grim.

It's like if we on the East Coast had 300 years to get out of the way of a massive hurricane and we decided we're fine with it, we're staying right the fuck here. But we're not really gonna prepare at all. What?

Article says they started to figure this out in the late 80's and early 90s. I get your point though.

[Beaver]

We should be hearing the Donald offering his condolences and help any day now.

and telling the people they're stupid for living there.

[iceman]

Article says they started to figure this out in the late 80's and early 90s. I get your point though.

I hear you. It's like we had 30 years to get ready for a storm, not 300. Seems like enough? Should be adequate warning? Who knows.