Why 'rocks as big as cars' are flying down the Dolomites

Re:Why 'rocks as big as cars' are flying down the Dolomites by clickety_clack on Wednesday August 27, 2025 @01:04PM (#45042223)

I worked as a geotechnical engineer for almost a decade, working on (amongst other things) landslides in mountain passes. It was a fun job!

I like this article. Geoscience isn’t well understood by most people, so I usually get reminded of the Gell-Mann Effect whenever I read a news article about it. But, this one correctly frames landslides as having created these feature in the first place, and that they were always going to fall at some point, rather than treating them as eternal features.

The features we see around us that seem so constant, like mountains, rivers, shorelines, lakes and seas, are all in a state of flux. Geological processes under some of our most populous cities are moving them by measurable amounts every year, and the numbers aren’t microscopic (up and down too, not just the sideways movement many people have heard about). Where once there were sea beds, there are now jagged mountains, and there will sometime be fields and then seas again.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by malyonsus on Wednesday August 27, 2025 @02:38PM (#45043340)

"Geologic time includes now", as they say in climbing.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by hydrogen7800 on Wednesday August 27, 2025 @03:18PM (#45043836)

I visited the Indian Ladder Trail not far from Albany NY, and there is a section where you walk under a rock ledge at the bottom of a sheer cliff. Even though it had probably been that way for millennia, I still felt a bit queazy walking underneath.

https://parks.ny.gov/parks/128/details.aspx

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Re:Why 'rocks as big as cars' are flying down the Dolomites by stockresearcher on Wednesday August 27, 2025 @03:56PM (#45044362)

There’s a nice stream that feeds into a river near a family member’s home in northeast Ohio. It’s got crystal clear water and a gravel stream bed - the kids love to flip over rocks to find and catch crayfish. On the opposite side of the bank is a sheer wall of sandstone about 20 feet tall. If you stand there for any length of time, you can hear it cracking and every 30-45 seconds you’ll hear (and maybe see) a small rock or a pebble come down and splash into the water. (It’s been doing that for decades or longer and nobody has ever seen anything larger come down so I’ve always felt it was perfectly safe to be on the opposite bank)

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Re:Why 'rocks as big as cars' are flying down the Dolomites by beezle on Wednesday August 27, 2025 @03:33PM (#45044024)

It is not an uncommon occurence in the White Mountains for stray boulders to injure and sometimes kill hikers. Just another reason not to wear headphones/buds while hiking, even a split second warning could be critical.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by lo_zamoyski on Wednesday August 27, 2025 @04:01PM (#45044418)

Reminds me of death, which, while not entirely the same, has certain similarities.

We always see death as something perpetually in the future. But death can strike at any moment, like the proverbial thief in the night. Not only that, when it does come, it will not be in the future. It will be lived and experienced in the now, just like this very moment.

It's like we're on a speeding train with no view of what's in front of us. At any moment, that train might slam into an impenetrable wall or hurtle off a cliff or sink into the depths of the ocean.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by Razengan on Wednesday August 27, 2025 @04:25PM (#45044730)

But soon hopefully AI can learn enough from to replicate me.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by hinkley on Wednesday August 27, 2025 @01:43PM (#45042657)

I learned recently that parts of Malaysia are subsiding more than 20 times faster than Venice. Ground water depletion can cause a lot of issues and at least in theory we could stop that.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by burkaman on Wednesday August 27, 2025 @02:12PM (#45043025)

This is a problem across the whole planet: https://www.propublica.org/article/water-aquifers-groundwate.... One thing I learned from that article is that the California Central Valley is 28 feet lower than it was 100 years ago because of groundwater depletion (https://en.wikipedia.org/wiki/Central_Valley_land_subsidence).

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Re:Why 'rocks as big as cars' are flying down the Dolomites by BurningFrog on Wednesday August 27, 2025 @03:13PM (#45043778)

Jakarta is sinking by 5-10 cm per year on average, and the northern part sinks by 28 cm per year!

The ocean is rising by 0.45 cm per year.

This is one reason Indonesia is building a new capital city on Borneo.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by hinkley on Wednesday August 27, 2025 @03:57PM (#45044363)

Yes! Jakarta seems to be the worst. They’re trying to build a whole other city to replace it.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by simonebrunozzi on Wednesday August 27, 2025 @03:04PM (#45043656)

And Miami.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by metalman on Wednesday August 27, 2025 @04:04PM (#45044455)

"Where once there were sea beds, there are now jagged mountains, and there will sometime be fields and then seas again." true, except next time around the mountains will have sedimentary metamorphic rock faces with pontiac bumpers embeded in them , anthrolithic assemblies?, there are many things made from alloys that are essentialy impervious to almost all chemical attack and other objects and piles so massive as to guarantee some things will retain a clear signature of bieng manufactured it is strange to think that things here now, will continue to exist into the far future

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Re:Why 'rocks as big as cars' are flying down the Dolomites by throwawayoldie on Wednesday August 27, 2025 @06:41PM (#45046222)

That blew my mind. Geology is going to be a wild discipline in the far future.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by financetechbro on Wednesday August 27, 2025 @08:23PM (#45046922)

Allow me to blow your mind once more. Earth is already starting to integrate waste into its geology

https://youtu.be/Q-0ONrHP_2w?si=NHuCQIE72PJndqR4

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Re:Why 'rocks as big as cars' are flying down the Dolomites by snickerbockers on Wednesday August 27, 2025 @09:00PM (#45047110)

There's a famous oopart called the London[, texas] hammer which is a hammer of 19th century vintage which was found fossilized and embedded in a rock in Texas. I can't remember what the explanation is but somehow it actually underwent fossilization over the course of a few decades and came out looking like it was tens of thousands of years old.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by WalterBright on Wednesday August 27, 2025 @04:41PM (#45044941)

The Seattle Times has, twice now, hilariously reported that the sea level at Seattle has risen 8 inches in the last century, caused by climate change.

It didn't question why this hasn't happened elsewhere in the world.

Further investigation showed that the land Seattle sits on has sunk 6 inches. (This may be due to the weight of the city buildings, or plate tectonics.)

There clearly is considerable difficulty in finding a reliable "zero reference point" from which to measure from.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by twoWhlsGud on Wednesday August 27, 2025 @06:56PM (#45046337)

https://earthobservatory.nasa.gov/images/150192/tracking-30-...

I don't see what's funny about 4 inches just in the last three decades. 8 inches over the last hundred plus years at seattle

https://tidesandcurrents.noaa.gov/sltrends/sltrends_station....

seems very much in line then (given the lower rates before 1992). "Further investigation" was perhaps motivated by the search for something besides truth?

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Re:Why 'rocks as big as cars' are flying down the Dolomites by WalterBright on Thursday August 28, 2025 @05:24AM (#45050146)

What's funny was the assumption that the ocean was rising rather than the land sinking.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by martinpw on Friday August 29, 2025 @12:59AM (#45060379)

Both are happening simultaneously

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Re:Why 'rocks as big as cars' are flying down the Dolomites by layer8 on Wednesday August 27, 2025 @06:54PM (#45046324)

The canonical “zero reference point” should be the geoid, but that also changes with time (https://en.wikipedia.org/wiki/Geoid#Temporal_change), so yes, it’s not trivial.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by consumer451 on Wednesday August 27, 2025 @04:53PM (#45045110)

The limestone in the Florida Keys is not sinking, afaik. There, around a foot (.3m) rise in the last 100 years is indicated by the sea level data.

https://tidesandcurrents.noaa.gov/sltrends/sltrends_station....

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Re:Why 'rocks as big as cars' are flying down the Dolomites by SlowTao on Wednesday August 27, 2025 @04:53PM (#45045115)

That is also happening in Manhattan/greater new York. The land is still rebounding from the ice age and the coasts happen to be at the point where they will slowly sink. Ocean level rise is also an issue but the base geology accelerates the issue in those locations

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Re:Why 'rocks as big as cars' are flying down the Dolomites by capitainenemo on Thursday August 28, 2025 @08:30AM (#45051355)

Yep. It's all along both coasts, but more to the north. https://en.wikipedia.org/wiki/Post-glacial_rebound

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Re:Why 'rocks as big as cars' are flying down the Dolomites by wat10000 on Wednesday August 27, 2025 @06:53PM (#45046311)

It has happened elsewhere in the world. Global sea levels have risen about 8 inches over the past century or so, and are currently rising about an quarter inch a year.

There are also regional variations caused by the change in gravity causes by the mass redistribution and ocean currents, so it’s not the same everywhere.

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Re:Why 'rocks as big as cars' are flying down the Dolomites by rene_d on Wednesday August 27, 2025 @04:48PM (#45045034)

Asianomics released a video on how withdrawing groundwater can dramatically lower the elevation of entire cities — I was surprised by how large an effect just a couple of years of human activity can have.

China's sinking land problem https://www.youtube.com/watch?v=nu_Y4hJmqGE

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Re:Why 'rocks as big as cars' are flying down the Dolomites by gcanyon on Wednesday August 27, 2025 @06:10PM (#45045965)

California's Central Valley has subsided as much as 28 feet in the past century: https://en.wikipedia.org/wiki/Central_Valley_land_subsidence

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Re:Why 'rocks as big as cars' are flying down the Dolomites by password4321 on Wednesday August 27, 2025 @05:09PM (#45045309)

Humans have pumped enough groundwater to change the tilt of the Earth (2023)

https://news.ycombinator.com/item?id=36366137

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