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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.
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?
Julian May already wrote about it in The Golden Torc back in the '80s and her story is way more interesting than this one :-)
Are you sure that flood didn't happen 5 thousand years ago?
The whole point is there were multiple flood events at different points in history. It's one of the reasons the stories are universal is that most areas had some form of great flood at some point in history. Look at it this way. At the end of the last ice age most of the population of Europe as well as much of the rest of the world would have lived along the coast much as they do now. Most of that land is now under water. The coast flooded through both gradual sea level rise and a series of flood events. When you are dealing with oral histories 2,000 years and 6,000 years can be hard to tell apart. Also the much quoted Biblical age of the Earth was calculated in 1650.
"In 1650, Archbishop Ussher published the Ussher chronology, a chronology dating the creation to the night preceding October 23 4004 BC."
There's no real dates in the old testament that can be referenced to modern dates. He came by that date by adding up ages of biblical figures some of whom are claimed to have lived 500 to 900 years. Coming up with an exact month is impressive given the fact few of the births were referenced to the actual age of the parents. Translated it was all guess work based on wild suppositions and had little to do with the Bible itself. Most of the Christian that quote the real age of the Earth have no idea how fabricated the date was. Personally I'll take facts over faith any day of the week.
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?
Me personally, I would have *loved* to have been born BC. That way, we count down our age, and your friends would greet you with, 'You're looking younger; how *do* you manage it' with each birthday!
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]
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