I mentioned in another thread that I've read about evidence that the Mediterranean Sea has become landlocked due to sinking ocean levels during various ice ages. This having the effect of opening up a far larger area of migration for early humans and also creating the most spectacular waterfall in history when the Atlantic Ocean once more poured through the gap. I am wondering if anyone on here knows about this? I've never even been to Niagra, this would be truly mindblowing. With forces like that at work is it any wonder that early man found no shortage of things to see as gods.
I believe it was in scientific american, it might have been discover magazine. The evidence was something about patterns of debris flow inside the straits. I'll do a google search and see what I find. I have seen others here disparage mainstream magazines (and those who read them, ouch) so perhaps it was just sensationalism?
okay, sounds interesting either way... if anyone here heard about that it'd be a media sensation... i live in a pathetic little country.
no luck on google search. I'll have to go through my back issues and see if I can find it. Seems like when I want to find something I can't find it, then when I don't want it it's right there. Wish me luck. This should probably be in earth science forum shouldn't it? Moderator?
try this: http://www.trussel.com/prehist/news153.htm http://www.ldolphin.org/meddead.html or use this as keywords: "ancient Mediterranean Sea dry lake bed falls"
When I searched before, I kept coming up with black sea links. The first link seems to deal with the black sea, the second has some mediterranean stuff, some evidence based on evaporites and fossils that shows the mediterranean might have been filled and drained a dozen times in a million years, 5 to 6 million years ago. Then it shows how this is not necessarily the case, then goes on to talk about the dead sea. It also seems that most of these black sea incidents had to do with reconciling with noah's flood, something which always sheds doubt in my mind. It's possible that the article I read was about the black sea not the mediterranean, but I don't think so, I'm positive it mentioned gibraltar. I went through all my back issues and couldn't find it. Not sure if I gave the particular issue away or just missed it. It was only a little blurb anyway. I'm sure I'll find it sometime I'm not looking for it, that's always the it works.
Did a little more searching, found some mention of a scientific american article from 72 (not the one I saw though), "When the Mediterranean Dried Up" by a dude name Kenneth J. Hsu, and also mention of more of Hsu's work up till 1983, when he wrote a book "The Mediterranean was a desert." Here's a link to a site talking about the book: http://www.geocities.com/Athens/Academy/6040/flood10.htm#n130 I'll read through some of this stuff tomorrow and give a summary. I wonder if the article I read was some new evidence favoring this theory. I remember it talking about layers of debris flow around the straits. Is there a law about not finding something when you need it? Something akin to Murphy's Law?
I'm sure I read something about this in some science mag, like AS, NG or ? if you are in college, ask the school librarian to find the article, Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! they'll probably find it on lexus-nexus, a mag & journal search engine. (smiles)
I've seen this recently mentioned in something I was reading. Can't say where, sorry. It said the same thing. Sea level drops drastically during ice ages because a huge percentage of the earth's water is locked into glaciers. Rivers and streams freeze and don't flow to the sea, and as more precipitation falls upon them it freezes too. This has been the explanation for the Bering Land Bridge, ca. 12,000 BCE, during which the first wave of human migrants reached the Western Hemisphere by simply walking. (The Athabascans, who were the ancestors of all the indigenous New World peoples south of the Rio Grande and most of the ones east of the Rockies.) Although recently the time of that migration has been called into question. Confusing archeological evidence suggests that it could have happened as early as 18,000 BCE when there was no ice age. In this case the migrants would have arrived by boat, simply following the coastline all the way from Siberia or northern China. It could have been that way, humans had invented boats long before that. They got to Australia around 40,000 BCE. This makes sense for the oceans because they are all connected. But... I'm just not quite sure what would happen once sea level dropped just far enough that the Mediterranean and the Atlantic were no longer connected. Is it not true that much of the loss of water from the oceans is due to increased mass of the polar ice caps? Would that not imply that a sea disconnected from the oceans would not lose as much water because it could not flow into the ocean to seek its own level? Does water evaporate fast enough from the Mediterranean -- during an ice age when the average annual temperature is lower than today -- that its level would drop the same distance as the ocean? Does the growth of the ice caps have no impact on the rate of change of sea level? The reason I wonder is that the "humongous waterfall" scenario implies that when the ice age ends and sea level rises, that the Mediterranean would not rise in synchronization with the Atlantic. The melting of the Alpine glaciers and the resumption of full flow of the European rivers, according to this model, will not be enough to cause the Mediterranean to rise as fast as the Atlantic. Therefore, this model tells us, the Atlantic will breach Gibraltar first and water will spill hundreds of feet down into the still-low Mediterranean. I find this model to be inconsistent. If the Mediterratean sea level will fall in synch with the Atlantic during the ice age, then it will surely rise in synch when the ice age ends, and the water on both sides of Gibraltar will reach the top at roughly the same time. Perhaps a mismatch of a few feet, but nothing that would rival Niagara Falls. If, on the other hand, the Mediterranean does not fall in synch with the Atlantic once Gibraltar has broken their connection, because the Mediterranean is not affected by the growth of the polar ice caps, then its level will be far higher than the Atlantic when the ice age ends and sea level rises. It won't have as far to go to meet the Atlantic when Gibraltar is breached, and again, there might be a mismatch but one of sub-Niagara proportions. I love the image that this model conjures up. People sailing their primitive little boats in a shallow Mediterranean, perhaps hunting to extinction the hapless whales whose ancestors were stranded there, and suddenly the cataract of Gibraltar comes down on them like the Wrath of God, creating a tide so huge that some enterprising dude might have invented surfing. This could have been the event that is the source of the myth of Noah's flood. Unfortunately, in my mind, the math doesn't work. No matter how in or out of synch the two seas were at the peak of the ice age, by the time the Atlantic was ready to breach Gibraltar, the Mediterranean would be very close to the same level. Can anybody tell me that I've made a mistake in my calculations?
I read about this years ago. I think the calculations suggested that the MEd would dry up, due to higher evaporation levels than the atlantic and not being replenished from it.
I'd need to see those calculations. It still doesn't ring true. You could just as easily say that the Atlantic will dry out faster because it's feeding the expanding polar ice caps.
Sure. I just cant remember where i read/ saw it on tv. But as far as I know, for certain, teh modern mediterannean requires the atlantic to refill it via Gibralter, to make up for evaporation.
I never considered the fact of europe and africa draining into the mediterranean. That's a good point. I'd be interested to see this worked out too. Here's what I found out about the evidence for a dried up mediterranean. In 1961 the American research vessel Chain from the Woods Hole Oceanographic Institution set out to explore the Mediterranean using newly developed CSP (Continuous Seismic Profiler) technology. This sent out acoustic waves into the seafloor, and received the echo from whatever hard surface might be under it. They found a reflective layer 100 to 200 meters below the surface, they called it the M-layer, and were at loss to explain how or why it was there. It seemed to mirror the topology of the mediterranean sea-floor, so it was laid down after the Mediterranean was already formed and at roughly the same proportions of the present-day. In 1970, the deep sea research and drilling ship Glomar Challenger, with Hsu as one of its principle scientists took core samples from various locations. ".... we hit the jackpot in Hole 124. On the morning of August 28, the Challenger was drilling south of the Balearic Islands in almost 3,000 meters of water." They pulled up a sample they called a "pillar of atlantis", it was composed of anhydrite and stromatolite. Anhydrite is said to be found only in arid coastal plains where saline ground water is close enough to the surface to be heated to 30 degrees celsius, if the water were deeper and/or cooler, gypsum would be formed instead. The stromatolite is layers of algal mats that form in intertidal areas, waters of 10 meters or less. The way these were layered with deep-sea ooze, stromatalite formed in shallow waters, anhyrdrites precipitated into the stromatolites, then more ooze, etc. suggested multiple dry periods. It mentions "brought up drill cores containing gypsum, rock salt, and various other minerals that could only have been formed by drying up of seawater." But it doesn't really mention gypsum in any cores, or exactly how the overall core samples shaped out in the article I'm using as a source. I'm going to try to find the book in the library and see what it says. It also mentions various deep canyons in the mediterranean in the south of france and under the sands of egypt that appear to have been carved by rivers rather than underwater processes. The topologies of these canyons seem to indicate that they emptied out into a sea that was from 1000 to 1500 meters below present day. The egyptian canyon was discovered when the Aswan dam was being built. Boreholes were drilled to find bedrock and analyze the sediments. A narrow canyon was found some 290 meters deep. Now here's the interesting bit. In this canyon was found 150 meters of pliocene marine mud, pliocene oceanic fossils. Now bear in mind that Aswan is 750 miles (1200 km) up the nile. So this seems to suggest that the refilling of the mediterranean was not a slow, gradual process with the Mediterranean rising to meet the rising Atlantic, but more of a catastrophic inflowing of water. In the second link given by Randolfo above it seems more intent on reconciling this with biblical flood legends. "Did the Mediterranean Sea really dry up? Was it once a very hot and dry desert? Probably not. There is another possible explanation for the vast salt and mineral deposits found at the bottom of the Mediterranean Sea. Let us explore Australian astronomer Barry Setterfield's hypothesis that atomic time and ordinary calendar time are related by the velocity of light. Using Setterfield's red-shift data to give us the expected value of c for events some millions of years ago in atomic time, we find that the 5 to 6 millions years BP (before the present) in atomic time was between 2875 and 2825 B.C. in ordinary dynamical time! (3) The salt sediments in the Mediterranean would then have been deposited in a mere 75 years, not over a million years, too short a time period for evaporation and refilling processes in the basin." Now that just smacks of crackpot physics to me... Any opinions? It seems that the real question is not wether the Mediterranean did in fact dry up, but at what rate it dried up, and at what rate it refilled. By the way, I'm almost ashamed to mention this, but I'll 'fess up. I found out where my original source for this topic came from. It didn't come from either Scientific American or Discover magazine (although I guess the source for my source probably did). It came from... gulp... a fictional book. "Evolution" by Stephen Baxter to be precise. I have been rereading it recently and just came to the part about the falls of Gibraltar. At least it's based on real science. The book is actually quite good. It's a fanciful tale of primate evolution spanning a 100 million years or so. It takes an example of a primate species in various times and tells a little story about them. The falls of Gibraltar part is right before hominids begin to form, before the chimp split from our tree. It details a trip south across the dried up Mediterranean by our chimp-like ancestors. The author does take a liberty or two here and there. A few made up species to liven up the cast every now and again. Then it goes into the future where it really becomes fanciful. Kingdom of the rats. *shivers* edit: I got my information here from: http://www.geocities.com/Athens/Academy/6040/flood10.htm#n130, if you're interested I would suggest reading that page for more detailed information.
Well, stephen baxter has a good reputation for the science, but i've never managed to read any of his books.
This might help: "Noah's Flood" by William Ryan & Walter Pitman. Book by 2 geologists published in Jan. of 1999 concerning the "Gibraltar Waterfall", the Black Sea flood, and their link to the various flood legends (i.e. Noah's Flood).
