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.
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.
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)
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.
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.
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.
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.
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.
seems very much in line then (given the lower rates before 1992). "Further investigation" was perhaps motivated by the search for something besides truth?
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
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.
"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
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.
I had a memorable experience when a basketball sized rock fell from a 1000' cliff above me. The rock made an unreal buzzing/humming sound as it flew through the air. My first though was that I should throw my helmet on, followed by realizing how little that would help if the stone actually hit me. It missed by a decent margin, maybe ~100', but that was way too close for comfort. Given the angle I couldn't tell if it was even going to miss until the last second.
Rockfall is no joke. Even well established parks like Yosemite have seen a number of deaths from it.
When I was a kid, we'd speculate what would happen if a penny fell off the Empire State Building and hit someone on the sidewalk. How far through the body would it go?
None of us realized it would reach terminal velocity very quickly.
I'll second this. Just finished his video on landslides the other day. Not only interesting, but also good info if you ever are considering a home on or around hilly terrain.
He has the most infectious curiosity, and I love the way that he presents geological mysteries as almost a true crime, feeding you little observations over time until you can _almost_ see the solution
"Second, although it's undoubtedly sad that one of the Five Towers came down, there were actually 12 towers to start with – they got shortchanged on the name because only five are visible against the sky from below. So, the fact that the number of towers doesn't match its official name is nothing new."
Immediately made me think of the 12 Apostles. (there were only 9 stacks at the time it was renamed)
It's down to 7 now, but it's expected new stacks will emerge as the coast is eroded. This is not some geological age timeframe. My father was a civil engineer on parts of the Great Ocean Road years ago, even moving one section of the road twice in his career as erosion exceeded their initial predictions.
An article on rock slides and every photo is stunningly gorgeous. That's the Dolomites.
Fun tidbit: The formation mentioned, the Five Towers, is right across the valley from where most of the movie "Cliffhanger" was filmed (the Tofane Group around Cortina d'Ampezzo).
I've heard 'rocks as big as cars' fully submerged, rolling down flooded creeks. The sound is eerie and unsettling - especially when you know what it is. Really gives an appreciation for the power of water.
Interesting article, and it brings back a lot of memories.
I've done three alpine hikes: the Tour du Mont Blanc, the Haute Route, and the Dolomites. The Dolomites were my favorite, for both the scenery (though all are spectacular) and for the quality of the mountain inns where we stayed each night. We spent one night at Rifugio Cinque Torri, which is not far from those rock towers in the story.
I took a lot of photos while hiking and while carrying the camera equipment was a bother, I am so glad I did as I can re-visit the trip, photo by photo.
The trail I followed for the TMB was not difficult, though difficulty depends on the trail you choose plus how much you want to cover in a day. I had good hiking boots, poles, rain gear, and a not-too-big pack with water, food, and clothing. I did not camp.
The terrain isn’t difficult - straightforward hiking with no special gear required - but you can make it as easy or hard as you like by varying the number of days you do it over. Famously the UTMB is a race that does roughly the same route in one push over two days, which is definitely difficult!
Italy is slowly waking up to the crumbling of the rigid petriarchical system of the past. Cracks are appearing in dolomite icons of the past who were once above reproach and they are falling from grace, one after another.
It depends if the unit is the European car or the American car. Since the dolomites are in Europe and this is the BBC we can assume they mean Ec, which is roughly equivalent to 10 m3.
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.
"Geologic time includes now", as they say in climbing.
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
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)
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.
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.
But soon hopefully AI can learn enough from to replicate me.
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
California's Central Valley has subsided as much as 28 feet in the past century: https://en.wikipedia.org/wiki/Central_Valley_land_subsidence
Humans have pumped enough groundwater to change the tilt of the Earth (2023)
https://news.ycombinator.com/item?id=36366137
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.
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).
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.
Yes! Jakarta seems to be the worst. They’re trying to build a whole other city to replace it.
And Miami.
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.
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?
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....
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
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.
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.
"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
That blew my mind. Geology is going to be a wild discipline in the far future.
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
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.
I had a memorable experience when a basketball sized rock fell from a 1000' cliff above me. The rock made an unreal buzzing/humming sound as it flew through the air. My first though was that I should throw my helmet on, followed by realizing how little that would help if the stone actually hit me. It missed by a decent margin, maybe ~100', but that was way too close for comfort. Given the angle I couldn't tell if it was even going to miss until the last second.
Rockfall is no joke. Even well established parks like Yosemite have seen a number of deaths from it.
When I was a kid, we'd speculate what would happen if a penny fell off the Empire State Building and hit someone on the sidewalk. How far through the body would it go?
None of us realized it would reach terminal velocity very quickly.
> if a penny fell off the Empire State Building and hit someone
There is a Veritasium video about that.
# How Dangerous is a Penny Dropped From a Skyscraper?
https://www.youtube.com/watch?v=16Ci_2bN_zc
If you enjoy this kind of content, I recommend Myron Cook on Youtube: https://www.youtube.com/@myroncook/videos
Geological mysteries, pleasant scenery, and calm explanation. Great for listening in the evening.
I'll second this. Just finished his video on landslides the other day. Not only interesting, but also good info if you ever are considering a home on or around hilly terrain.
He has the most infectious curiosity, and I love the way that he presents geological mysteries as almost a true crime, feeding you little observations over time until you can _almost_ see the solution
"Second, although it's undoubtedly sad that one of the Five Towers came down, there were actually 12 towers to start with – they got shortchanged on the name because only five are visible against the sky from below. So, the fact that the number of towers doesn't match its official name is nothing new."
Immediately made me think of the 12 Apostles. (there were only 9 stacks at the time it was renamed)
https://en.wikipedia.org/wiki/The_Twelve_Apostles_(Victoria)
It's down to 7 now, but it's expected new stacks will emerge as the coast is eroded. This is not some geological age timeframe. My father was a civil engineer on parts of the Great Ocean Road years ago, even moving one section of the road twice in his career as erosion exceeded their initial predictions.
An article on rock slides and every photo is stunningly gorgeous. That's the Dolomites.
Fun tidbit: The formation mentioned, the Five Towers, is right across the valley from where most of the movie "Cliffhanger" was filmed (the Tofane Group around Cortina d'Ampezzo).
I went to Bolzano to see the Iceman. I was not expecting the Dolomites.
They look like a movie set. In fact, they look like a movie set that you'd go, "Man, mountains don't look like that."
I'm glad they got good pictures for this article. The Dolomites are often clouded in.
Metric after the jump.
>Around 300,000-400,000 cubic metres of rock came down.
I've heard 'rocks as big as cars' fully submerged, rolling down flooded creeks. The sound is eerie and unsettling - especially when you know what it is. Really gives an appreciation for the power of water.
Interesting article, and it brings back a lot of memories.
I've done three alpine hikes: the Tour du Mont Blanc, the Haute Route, and the Dolomites. The Dolomites were my favorite, for both the scenery (though all are spectacular) and for the quality of the mountain inns where we stayed each night. We spent one night at Rifugio Cinque Torri, which is not far from those rock towers in the story.
I took a lot of photos while hiking and while carrying the camera equipment was a bother, I am so glad I did as I can re-visit the trip, photo by photo.
All three hikes are highly recommended.
Is Tour du Mont Blanc difficult? Do you need special equipment to climb or just a good pair of hiking shoes will suffice?
The trail I followed for the TMB was not difficult, though difficulty depends on the trail you choose plus how much you want to cover in a day. I had good hiking boots, poles, rain gear, and a not-too-big pack with water, food, and clothing. I did not camp.
The terrain isn’t difficult - straightforward hiking with no special gear required - but you can make it as easy or hard as you like by varying the number of days you do it over. Famously the UTMB is a race that does roughly the same route in one push over two days, which is definitely difficult!
I hope the follow up story is "why a simple bbc article locks up my browser".
So it's not just me, thank you.
Italy is slowly waking up to the crumbling of the rigid petriarchical system of the past. Cracks are appearing in dolomite icons of the past who were once above reproach and they are falling from grace, one after another.
that system was never that rigid, for it has feet of clay (and limestone)
But how many cubic meters are they?
It depends if the unit is the European car or the American car. Since the dolomites are in Europe and this is the BBC we can assume they mean Ec, which is roughly equivalent to 10 m3.
My initial scan of this link text made me think I was reading a mis-transcription of a certain Pogues lyric.
Because gravity.
Someone let me know when rocks as big as cars are flying _up_ the Dolemites.
This will never happen. EU regulations are incredibly restrictive.
It could be the Loonies throwing them down at Terra.
The Moon Is A Harsh Mistress.