We can see it in action in this experiment At first there's water trickles in It carries some sediments Which widens the hole More water flows in Carrying more sediments Opening a wider hole... Soon, you have a megaflood

The Mediterranean Sea was dry 5M years ago Then, a series of MEGAFLOODS filled it in a matter of months How did the Med dry up? Why did it fill so brutally? How would it have felt to be there? This is what we know:

The African and European tectonic plates have been colliding for millions of years, forming the mountains of southern Europe About 6M ago, water still poured into the Med from the Atlantic, but not through Gibraltar. Through what is now the Guadalquivir Valley

Fun fact: this flow helped form the Guadalquivir River valley, open to the Atlantic, so good for navigation that it was the base for the Spanish colonization of America. This is why American Spanish sounds like the dialect from this region. Details:

Then the plates keep pushing and closed that path, isolating the Mediterranean. Without water from the Atlantic, it started drying up

How do we know? A couple of reasons. Look at the relief of the ground under the Med ("bathymetry") Can you see these riverbeds carved into today's seabed? That only happens when water flows on ground above the sea

Some Med regions have salt deposits that are *kilometers deep*! (left map. red=rock salt) The Med locked about 10% of all the world's seawater salt! It noticeably reduced the salinity of the oceans Still to this day, the Med is among the saltiest seas (right) Most fish died

Then, 600k years later... BOOM! Water furiously tore through the Strait of Gibraltar, and water poured in Like 30,000 Niagara falls More than 100x all the water rivers discharge in the ocean worldwide Water raised 10m per day

We can see the marks of this event bathymetry maps to this day It opened a path 200km long 8km wide Hundreds of meters deep

Imagine how it felt to the animals living there Hominids were roaming Africa back then Your species has been there 400k years Suddenly, water appears You run away But water keeps rising The lucky ones lived on today's islands The rest drowned Massive extinction event

But hold on! This is just half of it! There's a path from Africa to Europe, through Malta/Sicily/Italy Water levels are high there—the Sicilian Sill It stopped the waters of the West Mediterranean Until it couldn't

The West Med filled It pushed east It reached Sicily It found an opening This happened *in two weeks* Then water started pouring over

This was a waterfall 1.5km high! Much higher than Angel Falls, the highest waterfall today How do we know? Because we know where it happened: the underwater Noto Canyon

This is how this event the Zanclean Flood filled the Mediterranean Sea in less than 2 years We're used to think of geological events happening in millions of years. Not here

I'll write more details about this in my free newsletter. Subscribe to receive it Did a similar megaflood happen in the Black Sea? What caused the opening in Gibraltar? Did this cause.. volcanoes to erupt? Why can we see evidence of this in the Nile?

Most of this research and videos comes from @danigeos Amazing work! Here's his YouTube channel [Other sources in my upcoming article]

I also wrote about a similar event that happened between FR & UK just 5k years ago! I might write about other megafloods, like the one in Washington State If you liked this, follow me. I write one of these threads every week or so

There’s a theory that an engineer named HRKLS (Hercules, Herakles) redirected a Spanish river via stone pillars-which still can be found- and wooden aqueducts- to clean out the straight of Gibraltar (Augean stables). Thus saving major cities formerly on the sea from falling dry.