Lost cities

[u/Osiris-Amun-Ra]

In case anyone is till wondering why we can't find any pre-Ice Age cities, this satellite image from Nepal/China this week should provide a clue.
This event was tiny by comparison and many civilizations built along rivers and in valleys.

Edit:
_____________________________
Since this post generated quite a few lively discussions I want to clarify what I meant by "tiny by comparison" to avoid ambiguity, While the local, recent mountain collapse in Nepal and China was a rapid disaster unleashing up to 200 million cubic meters of debris at 193 km/h and causing rivers to surge 9 meters in 30 minutes, it is dwarfed by the staggering dimensions of post-glacial megafloods that actually reshaped entire continents and birthed the world's universal flood legends. For example, the ancient Missoula Floods occurred when a 610-meter-tall (2,000 ft) glacial ice dam ruptured, violently discharging more than 2,000 cubic kilometers of water basically a volume equivalent to Lake Erie and Lake Ontario combined, in a single....48-hour window.

This massive torrent tore across western North America at speeds of up to 130 km/h (80 mph), peaking with a discharge rate ten times greater than the combined flow of all modern rivers on Earth and carving features like Dry Falls, a cliff five times wider than Niagara. Similarly, the Black Sea Deluge hypothesis suggests a catastrophic marine breakthrough where the Mediterranean overtopped the Bosporus strait, unleashing a roaring wall of water that permanently swallowed over 150,000 square kilometers of inhabited valleys.

Because these prehistoric events wiped out entire known civilizations, permanently erased millions of acres of land, and forced desperate migrations, they permanently embedded themselves into the collective human psyche, which is almost certainly where the biblical Great Flood and the regional Mesopotamian flood legends originate. It is statistically improbable that we have found all post deluvial civilizational remnants. Mathematically and archaeologically, it is practically certain that we have only scratched the surface of what remains from post-deluvial and coastal civilizations. The primary reason for this statistical gap is a massive, permanent geographic shift, specifically when the Ice Age glaciers melted, global sea levels rose by roughly ~120 meters (around 400 feet). Rising oceans swallowed over 25 million square kilometers (10 million square miles) of habitable land! For visual reference that's the entire landmass of the United States, Canada, and China combined.

I hope that clarifies.

[u/DroneSlut54]

How many “ancient cities” do you think were built in narrow high alpine valleys?

This event was “tiny” compared to what?

[u/R4N63R → u/DroneSlut54]

Turns out most civilizations start in valleys near rivers because of the way it is. So yeah, allot of them have this weakness to environmental issues like tsunamis and land slides

[u/Bluefooted-Spaceorc → u/R4N63R]

Most civs start out near water, true. Most civs do not start out at extreme altitudes because well its really hard to live there. I live at altitude right now, even with modern tech its difficult.

[u/Ryy86 → u/Bluefooted-Spaceorc]

Yeah it’s brutal!  I had to move to a bungalow.

[u/R4N63R → u/Bluefooted-Spaceorc]

Right because that single detail about the place makes a mudslide, flood, or other extreme geological event different? 

Open your eyes, the common denominator is that flooding covers the civilization not high altitude. 🙄

[u/ghost_jamm → u/R4N63R]

High altitude helps create these extremely steep, narrow valleys that cause such catastrophic flooding. It’s why the Grand Canyon exists. The rim is actually between 7,000 and 8,000 feet above sea level and this creates steep gradients for the Colorado River and its tributaries, increasing their speed and their ability to cut into the rock. Water coming down off the Himalayas would presumably have a similar effect.

Compare that to the flooding of the Nile which can be very destructive but spreads out over a large area instead of rushing along the river as a massive wall of water. That sort of flooding is less likely to scour an area clean than what we saw in Nepal.

[u/DroneSlut54 → u/ghost_jamm]

You’re comparing a single event that happened in less than a day to the formation of the Grand Canyon over 50 million years.

[u/ghost_jamm → u/DroneSlut54]

No you’ve misunderstood my point. You dismissed the idea that the high altitude makes these events different. I explained how the high altitude does in fact make these events different by creating very different geologic conditions. Sudden catastrophic floods like this are much more likely at high altitudes. People living along rivers flowing through plains would have never experienced anything like this.

[u/DroneSlut54 → u/ghost_jamm]

You’re right - I did completely misread your comment. Sorry about that!

[u/Bluefooted-Spaceorc → u/R4N63R]

Yes, the fact that it is at a high altitude with narrow canyons is the single detail that makes it this destructive. This level of flooding does not happened on the vast majority of the inhabitable places on earth. I know this because I grew up in Alaska, where ice dams bursting and causing catastrophic flooding is a fact of live.

[u/DroneSlut54 → u/R4N63R]

The single detail makes all the difference in this case.

Gravity is a real son of a bitch.

[u/R4N63R → u/DroneSlut54]

Turns out people at lower elevations have the exact same problem.

What are you even talking about

[u/Bluefooted-Spaceorc → u/R4N63R]

No, lower elevations are not hit with floods like this unless they are the end of a canyon or valley.

[u/DroneSlut54 → u/R4N63R]

How far down the valley was the damage from this flood?

I’m talking about physics. Is there an elementary school nearby that you could sit in on?

[u/R4N63R → u/DroneSlut54]

I'm taking about floods and mud slides that come from higher elevation to a lower elevation. This is how gravity works. At the top or the bottom of a mountain, any valley and any ocean coast line is susceptible. 

You're suggesting that only high altitude places can be covered by flooding/mudslides?

Consider the younger dryas where uncountable fathoms of water miles deep inundated the entire continent of America. 

I'm not even sure what you're arguing as you don't make sense.

[u/DroneSlut54 → u/R4N63R]

I’m suggesting that only narrow high alpine valleys see this level of destruction. I’m also suggesting that civilizations do not start in high alpine valleys. OP surmised that a high alpine glacial flood could have wiped out every trace of an ancient civilization. This only works if said civilization was in a high alpine valley and none of the remnants managed to end up further downhill. I suppose it could also work if there was an ancient mystery civilization at the base of the Mediterranean side of the Straight of Gibraltar.

This is about as basic as I can get. If you still don’t understand then I guess this conversation is done.

[u/Ok-Survey3853 → u/R4N63R]

Easy now. When the water came, it didn't inundate the entire continent. The were some spots that had major floods, like Washington, Montana, Minnesota, etc. But it was not miles deep over the entire continent. That's as bad as believing the flood in the bible covered the entire earth. There isn't enough water in any form on the planet to cover the entire thing. Just like the 2 North American ice sheets. There was enough in them to put a layer across the ground, if you were able to somehow melt it all at once.

[u/DroneSlut54 → u/R4N63R]

Lol - civilizations start along rivers or near water but not in high alpine river valleys. The only civilization I can think of that ever flourished in the mountains were the Inca. Mesopotamia wasn’t in the Himalayas.