The Mediterranean Was A Desert In the past three decades convincing evidence has been foun

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=====*=====*=====*=====*=====*=====*=====*=====*=====*=====*=====* The Mediterranean Was A Desert In the past three decades convincing evidence has been found that the Mediterranean Sea has completely dried up at least once, and probably many times. The first solid evidence came in the summer of 1970, when geologists aboard the deep sea research and drilling ship _Glomar Challenger_ brought up drill cores containing gypsum, rock salt, and various other minerals that could only have been formed by drying up of seawater. What was remarkable was that these minerals were found on the ocean floor, one to three kilometers deep, buried under as much as 200 meters of deep-sea oozes, which are the shelly remains of microscopic plankton that rain down on the ocean bottom. These oozes accumulate at a rate of about two centimeters per thousand years. [Therefore, the Sea dried up Ten million years ago and was re-filled] The story of the discovery is told in a fascinating book, _The Mediterranean Was a Desert,_ [Kenneth J. Hsu, Princeton University Press, Princeton, New Jersey, 1983. A Voyage of the Glomar Challenger] by one of the principle scientists on the expedition, Kenneth J. Hsu. Here are some extracts from this book. Speaking of another of the scientists aboard the ship, Hsu describes some of the early discoveries about the Mediterranean: Ryan had worked with a `continuous seismic profiler,' or CSP, which was a super echo sounder: besides recording sound echos bounced back directly from the sea floor, this instrument could send and pick up sig- nals of acoustic waves that were able to penetrate the bottom and reflect off hard layers several kilometers below. The instrument had been developed in the late 1950s, and in 1961 Ryan sailed with his mentor, Brack- ett Hersey, on the American research vessel _Chain_ from the Woods Hole Oceanographic Institution to explore the Mediterranean with the newly developed CSP. They soon discovered an acoustic reflector 100 to 200 meters beneath the Mediterranean sea floor. They had no idea what it could be or why it should be there, but for the sake of easy reference they named this mysterious layer the M-Layer, and its top, the M- reflector. American and French scientists continued the CSP surveys of the Mediterranean during the next ten years, and wherever they sailed they could iden- tify on their records the ubiquitous M-reflector. Furthermore, the geometry of this reflecting surface closely simulated the topography of the bottom of this inland sea; the sediments under the reflector covered the basement of the Mediterranean like a thick blanket of snow on a mountain plateau. Obviously the M-layer was deposited when the deep basin of the Mediterranean Sea had already been created and had almost the same bathymetry as it does today. [p. 7] Hsu describes the discovery of the key core: .... 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. Ryan and I had again stayed up into the early hours of the morning, when the drill pipe apparently hit the hard M-layer. The drilling rate dropped from several meters per minute to a meter per hour. Impatient with the slow progress, we went to bed just before dawn. We were not to rest long. Soon we were awakened by John Fiske, a marine technician, who came to report: `We found the pillar of Atlantis!' We dressed quickly and rushed to the ship's laboratory to see the new find. Lying on the long worktable was a beautiful core, which did indeed resemble a miniature marble column. That was the evidence I needed.... Our `pillar of Atlantis,'.... consists of anhydrite and stromatolite. This type of sediment has been found only on arid coastal flats. Prior to the _Chal- lenger_ expedition, my associates and I at the Swiss Federal Institute of Technology, supported by a research grant from the American Petroleum Institute, had studied the sabkha sediments of the Arabian Gulf. We dug scores of trenches on the sabkhas of Abu Dhabi and found anhydrite, a calcium sulphate salt, only in those places where the saline ground water was suffi- ciently close to the surface to be heated to tempera- tures exceeding 30 degrees Celsius. Where the water table was deeper and the water cooler, gypsum, or hydrated calcium sulfate, would be precipitated out in place of anhydrite. This finding is in accordance with chemical studies in the laboratory, which reveal that the transition temperature for calcium sulfate precipitated from saline ground waters should be above 30 degrees Celsius, or almost 90 degrees Fahrenheit. We thus have good reason to believe that anhydrite is not likely to be found in any environment other than hot and arid sabkhas, because surface temperatures and ground water chemistry elsewhere rarely permit anhy- drite precipitation. We are almost certain that anhy- drite could not be settled out of a deep sea. Even the Dead Sea is too deep a body of water to be heated hot enough to precipitate anhydrite; on the bottom of this salt lake only gypsum crystals are found. The anhydrite found under sabkhas was precipitated by ground waters like concretions in arid soils. Fine- grained anhydrite would accrete and grow together as nodules underground, replacing preexisting carbonate sediments. The nodules might range up to several cen- timeters in length. As the replacement proceeded toward completion, anhydrite nodules would coalesce to form a layer in which only wisps of preexisting car- bonates could be discerned. The dark wisps of carbon- ate in a white background of anhydrite look like the wire mesh used by farmers to make chicken-wire fences. Thus petroleum geologists who first encountered such anhydrite in their study of borehole cores dubbed the rock type `chicken-wire anhydrite.' We really do not know why anhydrite grows in this particular form. We can only rely on the repeated observations by sedimen- tologists during the last few decades that this vari- ety of anhydrite is typical of Recent and ancient sabkha sediments. Until we find evidence to the con- trary, we feel content to consider the chicken-wire anhydrite a signature of sabkhas. Stromatolite is another distinct sedimentary struc- ture. It had been considered a fossil or an inorganic structure of chemical precipitation until the 1930s when a British sedimentologist, Maurice Black, waded across the tidal flat of the Bahamas and found a dense growth of blue-green algae forming a thin mat on the flat shores. After a severe storm the mat would be buried under a thin cover of sediments, but the algal growth would persist and a new mat would be con- structed. This alternation would ultimately result in the laminated sediment called stromatolite, which means literally `flat stone.' Since the very exis- tence of algae depends on photosynthesis, the presence of a stromatolite structure is considered evidence of deposition in very shallow waters, commonly less than ten meters deep. In fact, repeated observations have confirmed that algal mats are a characteristic feature of intertidal environments. In the coastal areas between low and high tides, or the intertidal zone, of Abu Dhabi we found the current crop of lush growth in algal mats as well as old algal mats formed a few thousand years ago and now buried under the windblown sand of the coastal sabkhas. Transpiration of ground water led to precipitation of gypsum or anhydrite in these fossilized intertidal sediments. That August morning when I was called in to admire the `pillar of Atlantis,' I saw the same phenomena of a stromatolite partially replaced by nodular anhydrite. What could be a better indication that these sediments were formed on the tidal flat of a desiccated Mediter- ranean? The `pillar of Atlantis' was sampled from a layer of rock sandwiched between ocean oozes that contained abundant fossil skeletons of foraminifera and nanno- plankton.... the plankton found here once swam in the near-surface water of the oceans. After they died, their calcium carbonate shells fell to the ocean bot- tom and were buried and preserved as microfossils.... The deep-sea floor is a cemetery for billions upon billions of these tiny dead plants; the skeletons of nannoplankton may constitute more than ninety percent of the bulk of an oceanic ooze. When these oozes are mixed with fine terrigenous particles of clay, as they are in the modern Mediterranean, geologists use the term `marl oozes,' or simply `marls.' [pp. 10-19] There is strong evidence that there were several cycles of desiccation and reflooding. Upon closely examining the above mentioned Hole 124 core, Hsu found that The oldest sediment of each cycle was either deposited in a deep sea or in a great brackish lake. The fine sediments deposited on a quiet or deep bottom had per- fectly even lamination. As the basin was drying up and the water depth decreased, lamination became more irregular on account of increasing wave agitation. Stromatolite was formed then, when the site of deposi- tion fell within an intertidal zone. The intertidal flat was eventually exposed by the final desiccation , at which time anhydrite was precipitated by saline ground water underlying sabkhas. Suddenly seawater would spill over the Strait of Gibraltar, or there would be an unusual influx of brackish water from the eastern European lake. The Balearic would then again be under water. The chicken-wire anhydrite would thus be abruptly buried under the fine muds brought in by the next deluge. The cycle repeated itself at least eight or ten times during the million years that con- stituted the late Miocene Messinian stage. [p. 105] The Mediterranean basin has been deep for a long time: The first and most obvious support for the concept of a deep Mediterranean basin came from a study of the seismic records. The M-reflector had been discovered before the Leg 13 expedition, and everybody was then convinced that the sediment constituting the reflect- ing layer had been laid down in a Mediterranean basin whose topography was not much different from the bathymetry of the Mediterranean today. Except for some local disturbances the Mediterranean seabed 6 million years ago lay at about the same depth that it does now. In fact this was Ryan's reason for having once argued for a deep water origin of the evaporites. Other evidence was provided by.... shipboard paleon- tologists. The fossils in the sediments immediately underlying, immediately overlying, and interbedded with the evaporite beds all represented deep water creatures. One final reason for our not accepting the shallow bottom hypothesis derived from our knowledge of the geological history of the Mediterranean.... During the last 5 million years, the eastern Mediterranean had not foundered, which would have required regional ten- sion. On the contrary, the sea bottom had apparently risen under compression as Africa and the eastern Mediterranean seabed were pushed northward toward Europe. [p. 127] The remains of many canyons have been found, which had been cut into the sides of the Mediterranean basin when it was dry: Ryan, for his part, began to recall the gravels dredged up some years ago by Bourcart from submarine canyons in the Mediterranean. Apparently the French had been busy exploring the underwater topography of the western Mediterranean during the decade after the Second World War when Bourcart and his associates found many of these submarine canyons. The Mediter- ranean canyons seemed to be different from those found on the continental margins of the Atlantic and Pacific, however. They appeared to be drowned river valleys, whereas the Atlantic and Pacific canyons appeared to have been cut by submarine turbidity cur- rents. Furthermore, many of the canyons off the Cote d'Azur had not eroded recently, or during the Pleis- tocene, as the Atlantic and Pacific canyons had; they had been cut during the late Miocene. They were partly filled with late Miocene river gravels and then covered by ocean oozes of Pliocene age. The heads of many of these large submarine canyons could be linked to the mouth of modern rivers in southern France, Cor- sica, Sardinia, North Africa, and Spain. The bottoms of the canyons could be traced to about the level of the Balearic abyssal plain. The origin of the canyons and the gravels had consti- tuted a puzzle. Bourcart was convinced that the canyons had been cut above sea level by late Miocene streams. Not aware of any good evidence to suggest that the Mediterranean might have dried up, he pro- posed the less outrageous hypothesis that European and African continental margins had been bent down, drowning the Miocene coastal streams.... As we sat in the core lab admiring the red and green desert sedi- ments, we saw a new explanation to Bourcart's find- ings. The Mediterranean had been dry during the late Miocene, and we could envision a painted desert at the bottom of the present continental slope, stretching across the side expanse of what is now the Balearic abyssal plain. The desert floor then lay more than 2,000 meters below the level of the sea on the other side of the Gibraltar. Rivers in circum-Mediterranean lands were no longer emptying into an inland sea at sea level. Instead, they had to run a steep course down the newly exposed continental shelf and slope.... Rejuvenated streams made deep indentations on the edges of these plateaus and sculptured grand canyons on their way down to the dried up abyssal plain. Gravels were dumped in the canyons and variegated silts were piled up on alluvial fans at the foot of the escarpment. With this hypothesis, we not only explained the occurrence of red silts at Site 133 but provided at the same time a neat answer for Bourcart's canyons and gravels; we also resolved the long stand- ing mystery of the down cutting of the Rhone in south- ern France. [pp. 149-153] .... Shortly after we returned to port, [Ryan] received a letter from a Russian geologist, I. S. Chu- makov, who had learned of our findings through an article in the _New York Times._ Chumakov was one of the specialists sent by the USSR to Aswan to help build the famous high dam. In an effort to find hard rock for the dam's foundation, fifteen boreholes were drilled. To the Russian's amazement, they discovered a deep, narrow gorge under the Nile Valley, cut 200 meters below sea level into hard granite. The valley had been drowned some 5 million years ago and was filled with Pliocene marine muds, which were covered by the Nile alluvium. Aswan is about 1,200 kilometers upstream from the Mediterranean coast. Concerning this canyon beneath the Nile at Aswan, another book said: [Chumakov's] research had included the study of 15 holes drilled into the bottom of the Nile River just south of the Aswan High Dam.... Soviet engineers were helping build the new dam, and the holes were sunk to determine the depths to bedrock and the nature of the sediment on top of it. This revealed that under the relatively flat bottom of the present river the bedrock forms a canyon some 290 meters deep, now filled with sediment. The lowest part is a narrow gorge with almost vertical walls. Most remarkable, Chumakov found, is the nature of the sediment in the bottom 150 meters of this canyon. It proved to be filled with oceanic fossils of the Pliocene. In other words this canyon 1200 kilometers (750 miles) up the Nile, was once flooded by a sudden incursion of the sea some 5.5 million years ago. The most likely explanation, Chumakov believed, was that the canyon was carved when the Nile flowed into a Mediterranean Sea 1000 to 1500 meters lower than today. Then rapid filling of the sea sent salt water up the canyon, and only when the latter silted up higher than the exist- ing sea level did the accumulating fossils change to fresh water forms. [Walter Sullivan, _Continents In Motion_, pp. 166-167, American Institute of Physics, New York, 1991.] _The Mediterranean Was a Desert_ continues: In the Nile Delta, boreholes more than 300 meters deep were not able to reach the bottom of the old Nile canyon. Chumakov estimated that the depth of the incision there might reach 1,500 meters, and he visu- alized a deeply buried estuary under the sands and silts of the modern Nile Delta. Chumakov was right; a narrow 2,500-meter-deep canyon under Cairo was recently discovered during geophysical explorations for petroleum in Egypt. Note that 2,500 meters is 8,200 feet. This is much deeper than Hell's Canyon of Idaho and Oregon, the deepest in the world today. Chumakov was not the only one who found buried gorges. Petroleum geologists exploring in Libya described their surprises. First, their seismograms registered anomalies: there were linear features underground transmitting seismic waves at abnormally high veloci- ties. Drilling into the anomalies revealed that they were buried channels incised 400 meters below sea level. The geological record tells the same story: vigorous down-cutting by streams in the late Miocene and sudden flooding by marine waters at the beginning of the Pliocene. Ted Barr and his coworkers in the Oasis Oil Company, based in Tripoli, Libya, concluded in a report that the Mediterranean Sea must have been a thousand meters or more below its present level when the channels were cut. They could not get their manuscript published in a scientific journal since no one would accept such an outrageous interpretation. Still other buried gorges and channels have been found in Algeria, Israel, Syria, and other Mediterranean countries. [pp. 173-5] In 1975 another expedition of the _Glomar Challenger_ was undertaken, with Hsu aboard. .... We managed to do what we could not have done five years previously--namely, to penetrate the Mediter- ranean evaporites so as to obtain a record of the ear- lier Mediterranean history. We found unequivocal evi- dence that the Mediterranean had been a deep sea, for 15 million years at least, prior to the Messinian dessication. [p. 182] Interestingly, Hsu makes some comments about his initial skepticism and later acceptance of the revolutionary seafloor spreading hypothesis I've already mentioned in con- nection with plate tectonics. This hypothesis is strongly confirmed by the presence of symmetrical magnetic stripes on either side of spreading centers. Correlating the width of the magnetic stripes with the duration of successive reversals of magnetic poles, the sea floor spreading hypothesis should provide a means of determining the age of the ocean floor: the farther away from the ridge axis, the older the ocean crust would be, and the ratio would measure the rate of sea floor spreading. The Leg 3 [Deep Sea Drilling Project] expedition to the South Atlantic was planned to test the hypothesis. By drilling, sampling, and dating the ocean crust, we should find out if the ocean floor at a number of chosen sites was indeed as old as the hypothesis predicted. Working on _Glomar Challenger_ during the Leg 3 drilling, I witnessed the most amazing confirmation of this concept of sea floor spreading. We bored ten holes, and the age of the sea floor at every site was almost exactly that predicted by the hypothesis. It is always hard for me to accept other people's bril- liant ideas and admit my own errors in judgment, but faced with ironclad proof, I had no choice but to join the `revolutionaries.' [pp. 31-2] The previous material on the Mediterranean's drying up con- tains abundant evidence that creationist speculations on the geological events related to the Flood are incorrect. The most damaging is the finding that the Mediterranean basin has been deep for a very long time. Whether or not the 15 million or more year time spans mentioned above are correct, it is clear that all the described geological features could not possibly have been formed during and after a great Flood just 4000 some-odd years ago. If the "shallow sea basins," which would have included the Mediterranean, were deepened during the Flood, how were the buried gorges such as the Nile's formed? Especially so since the sea basin would have been filled with seawater? How could up to 200 meters (650 feet) of sea-bottom oozes, consisting of mostly the skele- tons of plankton, have been deposited in such a short time span? Especially since the current rate of accumulation is only two centimeters per thousand years? If the Mediter- ranean were shallow prior to the Flood, when and in what manner did all the evaporites become deposited? Especially since there is clear evidence that there were a number of cycles of drying and flooding, that deep sea oozes were interbedded among the evaporites, and that the oozes have been shown to evenly blanket the basement rock of both shal- low and deep regions. The only logical conclusion is that the creationist explanations about the supposed "shifting of the earth's crust" during and after the Flood are erroneous. Their explanations of salt deposits do not take reality into account. Alan Feuerbacher


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