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Mediterranean Might Have Filled In Months
An anonymous reader writes "A new model suggests that the Mediterranean Sea was filled in a gigantic flood some 5.3 million years ago. According to Daniel Garcia-Castellanos' paper in Nature, the sill at the Straight of Gibraltar gave way rather suddenly, with 40 cm of rock eroding and the water level rising by 10 m per day at its peak. They imagine a shallow, fast-moving stream of water (around 100 km/hr) several kilometers wide pouring into the basin with a flow greater than a thousand Amazon rivers — that's about 100,000,000 cubic meters per second." The flood would have dropped worldwide sea levels by 9.5 meters, probably triggering climate changes. In this model the Mediterranean filled in anywhere from a few months to two years at the outside.
just had an orgasm.
Are you sure that flood didn't happen 5 thousand years ago?
It has been done, it can be undone: http://en.wikipedia.org/wiki/Atlantropa
Whatever the arguments against it, I suppose it is within reason that it could be done. But should it be done?
This research has inspired me to save the planet.
Consider, what are the 3 big problems with AGW?
1. The climate gets warmer than we'd like.
2. The sea levels rise.
3. Mass famine as the farmland goes dry.
4. The extra CO2 acidifies the oceans screwing with the fishies and shellfish.
So now I give you the perfect geo-engineering solution to all these problems!
Step 1: Set off a bunch of Nukes in a desert somewhere, excavating giant holes in the ground.
Step 2: Dig a little path to the ocean and have it fill in the holes.
Benefits: First the ocean levels go down to their regular levels, yay! Second the resulting Nuclear winter offsets global warming, another yay!
Third the desert is now ocean front property and not as deserty, maybe more farm land (do this in Africa for bonus famine offsetting points).
And lastly to handle the acidy oceans... the fallout from the Nukes mutates the fishies and shellfish to adapt to the carbonic acid oceans!
Now can I have my Nobel Peace now? Other than some minor side-effects this should be a pretty effective solution.
I stole this Sig
Julian May already wrote about it in The Golden Torc back in the '80s and her story is way more interesting than this one :-)
This story would be much cooler with a video clip.
Jesus was all right but his disciples were thick and ordinary. -John Lennon
Well, before that, it was a lake. Where do you think the aliens stole all the water from?! It was freshwater then, of course. Sadly the Sahara Forest never recovered.
Don't think of it as a flame---it's more like an argument that does 3d6 fire damage
This one happened almost 5 million years before modern man first arrived. There are several better floods, if you want to explain the presence of so many flood stories in ancient cultures. Really, there are several candidates that could explain all of those stories about the entire (known) world getting flooded, and Noah isn't the only ancient story about the world being flooded. Frankly, such things being passed down in oral history is only reasonable. If anyone had seen this flood, you can bet that every generation for a very long time would have heard the story!
It's like all those myths about dragons, which are spread through many different cultures. Of course they never really existed, but they have a basis in reality: people probably found dinosaur fossils and the legends grew. Just because things have been legendized doesn't mean they have no basis in fact.
Ok, just once, giving you the benefit of doubt concerning trolling:
The mediterrean doesnt have that many rivers flowing into it, but is in a relatively hot climate.
This means that much more water evaporates than it recieves.
Several times in history, the connection of the mediterrean with the other oceans (i.e. the atlantic) was closed by the way of plate tectonics,ice age, etc (plate of africa going north and forming the alps...)).
During these times, the entire sea evaporated away. IIRC, it was once MUCH deeper, but at the ground there are a few km of salt and sediments from those times.
But such things cannot last. Thousands (if an ice age) or millions of years later there was a breach somewhere to let water enter (be it by way of an earthquake, rising water level of the outside oceans, etc). And after that, erosion had its way.
It must have been an unimagineable awesome display ...
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
Noah shit??
Probably the best small-scale example of how violent this event would have been is given by the flooding of an open-air mine in Malaysia. The rocks separating the mine from the sea became unstable and collapsed, filling the whole thing in minute or so: video!
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Please correct me if I'm wrong, but it looks like the science is even shakier than that.
The Mediterranean could easily have formed over tens of thousands of years (it says so in the article), but they're puzzled that there's a U-shaped sediment deposit instead of a the V-shape made by slow water erosion.
Glacial valleys are also U-shaped. Glaciers have covered that area many times over the last 5 million years.
Tectonic movement could also smooth out the normal V-shape of slower water erosion. All patches of earth are constantly rising, sinking, and/or moving horizontally. The middle of the V rising could explain the U. The sides of the V sinking or moving away from the center could also explain the U. Notice the mountainous areas around Spain and NW Africa. There is a tectonic plate boundary next it. There's been plenty of movement in that area over the last 5 million years.
Multiple rivers could also have broken into the Mediterranean and eventually carried off the bits of land in between, also explaining a U-shape, but over a longer period of time than the "2-year max" their simulation shows.
Here are 3 less exciting, but (as far as I can tell) plausible explanations. It could also be a mixture of these and/or other factors we haven't considered.
It looks like they simply chose one hypothesis that sounded impressive and made a computer simulation of it.
The Mediterranean flood hypothesis is not new - these authors have just done more work on the geology. They lean against the giant waterfall idea ("We do not envisage a waterfall..."), which is a shame - I always liked the idea of a supersonic waterfall.
"The flood would have dropped worldwide sea levels by 9.5 meters, probably triggering climate changes."
OMG, something MUST be done to revert the planet to it's pre-Mediterranean-Sea-filling pristine state, or you will all rot in Al Gore's climate Purgatory!
Huge salt desert in Australia which used to be an inland sea. It's about 15m below sea level
Dig 2 canals. boom. you have an inland sea again. Australia stops being a huge desert.
You'd need 2 canals at opposite ends to pump the salt out.
Deleted
And you just know there are cave drawings somewhere showing jackasses trying to body surf in it.
Computer models of chaotic systems may not reflect the exact performance of what they are modeling, but they can demonstrate the range of possible and likely results.
And the model is not just based on mountain streams; it is also based on some much larger and more recent events, such as the creation of the Snake River Gorge (300 meters deep in a matter of weeks) and the flooding of the English Channel. Water has enormous power to carve up rock, and the conclusion of the study is not in any way extraordinary; it's what anyone who has ever stood at the bottom of the Snake River Gorge would even find rather obvious.
The problem is that throughout the colonial era it was widely assumed by learned men that the Earth is a stable place where a comfortable equilibrium reigns. What we have found in the last 40 years or so is that the Earth is actually an extraordinarily violent and often inhospitable place, and the relative stability of the last few centuries is an exception, not the rule. If we hang around here long enough we will have to deal with violent changes, and efforts to engineer such a complex and sensitive system might make things worse. The problem is that we are engineering it by pumping carbon into the atmosphere, and a sensible person might conclude knowing what the system is capable of that kicking it might not be such a good idea.
Brackets contain world's first nanosig, highly magnified:[.]
Well, at least all denominations have the birth of Christ wrong.
According to Daniel Garcia-Castellanos' paper in Nature, the sill at the Straight of Gibraltar gave way rather suddenly, with 40 cm of rock eroding and the water level rising by 10 m per day at its peak.
I'm relieved to know the Strait of Gibraltar is not gay; I was convinced he was hitting on me the other day.
I always thought it would be cool to cut a canal from the ocean to Death Valley. With the heat there you would get a lot of evaporation and could sustain a current that you could use for power generation. Plus you could cool the air and get some rainfall. We can make our own little Med.
I love Jesus, except for his foreign policy.
I'm a geology grad student doing a thesis on tectonic geomorphology. I read this article with great interest; my research is on mountain rivers/streams so I know a bit about this kind of thing.
Your alternate theories don't really work, for a variety of reasons. I'm not an expert on all these topics, but I'll explain as best I can and hopefully anyone that might know better will correct me :)
The glacier theory doesn't work because glaciation did not, in fact, reach that far south. The area has stayed at a relatively stable latitude for the past 250 million years at the least (check out a plate reconstruction for 30 Ma compared to the present - the site has earlier reconstructions as well). Even during ice ages, glaciation never got that close to the equator. This is beside the fact that you can actually distinguish between a glacial valley and the kind of thing they're saying this is - based on the shape, type of sediments, and so on.
Tectonic movement doesn't operate on the same time scale as erosional and stream processes. Tectonics has a major influence on the way rivers operate - in fact that's what my research is about - but not in the way you're speculating. You might be surprised how well preserved rock formations are compared to when they originally formed - it sounds like this one is more or less the same as when it was deposited, which is common in most areas. Tectonics is constantly shifting the crust, yes, but not as much or as fast as you're supposing, and even then this is a relatively inactive area.
Now, your final theory is actually about right, but if you change it to follow how river erosion actually works, then you're basically saying what the researchers here are saying. Their description is a bit misleading, depending on how long you think this took to occur (and I would lean more towards it taking longer - two years as they say, or even a little more, but I don't know the specifics of where they came up with that figure).
The valley shape and sediment type suggest a braided river system, with multiple small, fast streams covering a broad area, constantly shifting left and right. As they drop sediment and fill in depressions, the areas where water is not flowing become the new depressions, so the streams shift back and forth, filling the area with sediment evenly. The coarse of meandering rivers (which are more mature and have slower flow rates) can change on sub-decade time scales, and braided rivers are constantly shifting. Now, the important thing is that these braided streams don't carve v-shaped valleys - they spread themselves out broadly, eroding laterally.
Thus, the initial break would have carved a v-shape valley, but it would quickly erode laterally. Most of the initial deluge would not be recorded - it simply wiped everything away. What's left is the wide valley that got flushed out, and the coarse deposits that filled the valley from the braided streams that existed near the end of the deluge, when flow rate was still high but not enough to wipe away absolutely everything.
One of the most interesting things about this research is that it supports the idea that these things can happen catastrophically. In the 1800's, during the early days of geology, there was a huge debate surrounding whether geology happened catastrophically or gradually. Now, the theories those guys were pushing were ridiculous (although a lot of fun), but the question of time scales is still relevant. It became clear by the early 1900's that gradualism is more realistic, and all of geology is essentially based on that - almost anything can happen if you give it enough time. It's the same conceptual leap that you need to understand biology and evolution, but with geology there is even more time to play with, and physics can easily explain how rocks are affected by forces over long time periods.
This led eventuall