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| anomalies record in the ice | Posted by Sguongy |
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This may be lengthy and I wonder how often this site is checked. Maybe no one is home anymore. I can see much of what you are saying and agree. First, one concern we have today from a nuclear war is a nuclear winter. the debris that would be strewn into the atmosphere would likely darken the sky and reduce surface temperatures dramatically. Now, let's say the Veda is correct and a nuclear war took place. Afterward, as is usually the case man goes, nuts, we all lost. Then again if we blow the ice cap and create a lot of precipitation and it pulls the dust from the air and we can afford to move our civilization as opposed to losing it we could come back a winner. So, they prepare and with methodic intention blow sections of the ice caps,existing then and it almost works. one small side affect you already described. they know the possibility of a mass shift could reset the land mass of the planet but hoping for the best, they take a chance. It's live and die no matter what anyhow. So earth starts her little wobble as the rain/snow falls back to surface with much sediment, redistributing land mass and water as ice and snow. This could in ways explain anamolous ice samples containing soil and debris not consistent with the area taken from as well as a shift in poles which is almost already a given and leave us other anamolies that only make sense in a short nuclear winter as opposed to an era long ice age. Helps explain mammoths found in areas of the north with fresh greens in their mouths as an almost instantaneous amount of cold precipitaion fell from the sky. Literally freezing on contact in the already near global nuclear winter. The aftermath of warming and floods and likely volcanic activity then restructering the very terra and the geological table goes out the window. Another reason all era of dinosaurs and prehistoric animals are found in the same strata and near each other in large groups. See the web on Mt.St. Helens, USA and the results now 20 years later and the formation of geological layers in a matter or hours and days. WE did it in physics class.
Anyhow, I was thinking on these lines looking for the thread that binds it all together. I also feel that an asteroid strike could have caused the same nuclear winter conditions. Problem is where did it hit? Lastly, a super volcanic explosion. SO why did the ancients blow the cap. Any one is a good call, but the real question of the hour is this. Where did they get the technology? Maybe we didn't come from stupid apes. Well at least not all of us See more of this discussion:anomalies record in the ice
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| Our Universe's Likely Structure | Posted by James Kibera |
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Our Universe's Likely Structure
Does Negative Gravity Matter Exist? Suppose at 5:30am our sun became a negative gravity sun of equal but opposite magnitude with the earth held to it's orbit around it. As it sets to rise the stars will start to disappear from sight as their radiation begins to be, NOT overshadowed, BUT overpowered by the NEGATIVE ENERGY radiation from it according to -E=-MC2. At daybreak, it would be totally dark as its very chilly cold radiation overpowers even the brightest sportlite, dropping their temperature towards the negative Zero Kelvin range and on toward the negative gravity matter temperatures! The sun would be the most black sport you've ever seen. Meaning? If there are negative gravity galaxies, they would have reported their presence to us through their radiation! We would be seeing both bright stars and dark stars in the sky, say, using parabolic lens telescopes. But to date no such a phenomenon has been noted. Hence, we could safely conclude that (-) gravity matter could be a fable An Etheristic Space or An Empty Void Universe? According to Faraday's law a changing magnetic field produces CLOSED LOOPS of electric fields around it. Also, according to Ampere law with Maxwell's displacement-current modification, not only does an electric current, but ALSO a changing electric field through a surface bounded by a closed loop, will produce magnetic fields which are closed loops around it. But radiation has been proved to be transverse plane polarized waves in their direction of motion. This could ONLY be possible if isolated charges are an inherent part of a photon! And since radiation has been shown to have momentum, e.g, laser beams have been shown to blow away pieces of plastic, and since radiation in a uniform medium travels in a straight line, then both the +ve and -ve POINT CHARGES that make up its electric fields are of equal mass/charge ratio. Hence both Faraday and the modified Ampere laws do prove Einstein wrong that photons are free of electrical charges when in free space. (Another phenomenon that I had read about some over 25yrs ago that seems to further advocate that the electromagnetic fields that make up photons even when in free space consist of charged matter is the observation that Gamma rays have been seen to change into electron-positron pairs and vice versa. This could ONLY mean that photons consist of separable charges, unlike Einstein's deduction that photons are free of electrical charges when in free space!) Since POINT CHARGES thus seem to be an inherent part of radiation, then it follows that a photon is a transverse-longitudinal hybrid wave due to the curved mobility of this point charges in a photon's magnetic fields. Now, according to the inverse square law, each of this point charges in a photon has an effect throughout the universe. Hence, due to its longitudinal aspect, each photon would move along with its SHARE of SPACE ETHER. And this is one of what Einstein failed to notice! The Packet Nature of Energy Energy, whether radiation or particle form, seems to exist as packets, unlike sound waves or water waves. How could this phenomenon be explained? In part 2, I clarified that since a time varying magnetic field produces CLOSED LOOPS of electric fields (i.e, of Maxwell's displacement current) and vice versa, and since there is NO WAY you may integrate LOOPs to form independent poles, then charged matter is an integral part of a photon since radiation is polarized! This also means that radiation is a hybrid of longitudinal and transverse waves due to the curved path taken by this charged matter moving through the magnetic field of a photon. In other words, a photon's magnetic field defines its size, lenghth, shape and the path taken by its radiation energy. Hence, electromagnetic energy will bundle itself up into packets rather than spread about like in sound or water waves. Moreover, the parallel mobility of like charges in a photon would result in a powerful force of attraction between them that counteracts the electrostatic force of repulsion between them. This would further enhance the wave packet to hold tight together as if it were a packet. Hence, it has been shown that each wave packet energy, E=hv, where v is its frequency and h is Plunk constant. We call the rectiliner wave photons as radiation. We would then expect that a particle to be a confided, stationary electromagnetic wave pattern of this longitudinal-transverse hybrid wave of either cylindrical or spherical coordinates. Since, c=lv where l=2(3.14)r, then from E=mc2=hv, the mathematical estimate of the size of a proton is 2.53*10^(-16)m, which slightly deviates from experimental values. Hence, both radiation and confined photons, that is particles, seem to be packets of electromagnetic energy. Then you would expect an electron to be about 1840 times larger than a proton in diameter! In part 4, I'll show Einstein's loophole in relativity. A Loophole In The Special Theory Of Relativity The Special Theory of Relativity postulated by Einstein states that: 1). Absolute uniform motion cannot be detected, and 2). The speed of light is independent of the motion of its source. The consequence of his postulates is that: Every observer measures the same speed of light independent of the relative motion of the sources and observers. An Etheristic space does bring us to the same postulates and postulate's consequence. Consider one thing taken for grated in considering Michelson-Moleys experiment for measuring the speed of light. It is ASSUMED that if space is Etheristic, then a body in it could have a relative motion with the ether in ANALOGY to a boat on a flowing river. In parts 2 and 3 it was shown that the electromagnetic fields of photons consist of charged matter. Now the electromagnetic fields of each point charge obey the inverse square law and fill the whole universe. Hence, a moving Electomagnetic field results in a respective motion of the ether in which they are in. Hence, each photon or particle moves along with its SHARE of space ether. It's like a boat moving along with the river it's in. Therefore, on a big planet like the earth, despite the orientation or earth's mobility, you would measure the same speed of light. Hence , 1). Absolute uniform motion cannot be detected, 2). The speed of light is independent of the motion of its source. Consequence: Every observer measures the same speed of light independent of the relative motion of the sources and observers. >From there, how time dilates and length contracts follows the same argument as for special relativity. What could fundamental forces be? This is what I try clarify in the next part. Fundamental Forces - What Could They Be? Let's consider the probable structure of other basic force fields other than electrostatic charge, namely; magnetism, gravity, strong and weak nuclear forces. To be able to explain both magnetism and gravity, I postulate that point charges that make up the electric and magnetic fields, those of photons inclusive to be CHARGE CLOUDS of a thermodynamic ether of fundamental particles I'v termed as KIBIONs, of both +ve and -ve kind of extremely high charge/mass ratio. Being thermodynamic, the Kibions that make up each charge cloud are at different energy levels with a single Kibion occupying its centre resulting in the charge cloud being electrically charged. Each of these charge clouds I'v termed as a GRAVITON. Consider a moving point charge. It's electric flux part that results in a magnetic field is that normal to its motion and NOT that tangential to its motion. But it is this normal component that would result in gravitons to SPIN! This spinning effect of gravitons is what I consider to be magnetism. In other words, magnetism is the GRAVITONs' SPIN VECTOR. This explains how magnetic poles always occur in pairs. Just as a moving ball which spins normal to it's motion exerts a normal force to its motion and spin axis, so would a mobile graviton that spins normal to its motion induce an electric field just as does a mobile magnetic field normal to its velocity. Now consider a changing electric current in one wire with another parallel to it. The spinning gravitons would induce an electric current whose magnetic field opposes the change producing it, thus clarifying mutual induction. Moreover, due to their inertia by having some mass, gravitons would resist a change in their spin vector thus explaining self induction. What about gravity, what could be its nature? Consider the nature of a graviton as I'v proposed it. It's a charge cloud that consists of Kibions at various continuous energy levels from its centre. Since it consists of charged Kibions, it's a charge cloud of electric dipoles. Hence each energy level acts like a skin, though gaseous, with a kind of SURFACE TENSION due to Kibion dipoles. Hence, apart from the electrostatic force between a +ve and a -ve graviton, they would experience a pull towards each other due to the contraction of their various merging pseudo-surfaces of their various energy levels, despite putting them together in electrically neutral pairs. The resulting force is what I term as GRAVITY. What about the strong and weak nuclear forces, how does this Etheristic space explain them? In it, a fundamental particle is just a standing wave pattern of a hybrid longitudinal-transverse wave or a combination of them. At various instants, it's electrostatic and magnetic fields have various magnitudes and orientations in space. Hence, they would experience corresponding instanteneous forces from other particles, analogous to Van De Waals forces between molecules. According to mc2=hv where v=c/l, these forces between a proton and a neutron would be extremely strong due to their small size and quasi-similar frequencies, thus clarifying the strong nuclear forces that bind nucleons together. But between an electron and a neutrino (if they do exist,) according to the inverse square law, such kind of forces would be relatively very very weak, thus explaining the weak nuclear forces. Such forces between a positron, or an electron, or a neutrino with a nucleon would be very weak due to the vast difference both in size and frequency, about 1840 times according to v=E/h=c/l. Hence, it would be very difficult for a proton and an electron to get bond together as nucleons do, hence forming very stable hydrogen atoms which mainly react chemically to form molecules unless at extreme temperatures such as in the sun. In part 6 other natural phenomenons would be considered. Final Comments & The Origin Of The Universe. All through this article, it has been shown how the basic laws of nature declare strongly that we live in an etheristis universe. Faraday's law and the modified Ampere law with Maxwell's displacement current's demand that a changing magnetic field produce CLOSED LOOPS of a changing electric field, and vice versa. And since radiation is polarised, then these laws demand that space to be etheristic, that both electric and magnetic fields consist of ELECTRICALLY CHARGED MATTER! Hence Einstein's non-etheristic space seems very unlikely though arriving at the correct mathematical equations. And since there are many proposed structures of the universe based on his non-etheristic Special Theory of Relativity of which I have proved to be wanting, then ALL these structural proposals of space, by being based on a FAULTY FOUNDATION, are wanting too! Now what about the origin of the universe! Could it have eternally existed? Now the first law of thermodynamics states that the total energy of the universe is a constant, while the second states that entropy (i.e, in lay man's terms, the USELESS ENERGY) of the universe is increasing. Hence, there was a time when there was NO entropy! Meaning? The universe had a beginning for it hasn't existed eternally. The sun hasn't burnt itself out nor has ALL the uranium in the earth decayed into the metal lead! But what kind of beginning did it have. Uranium dating reveals that the earth could be billions of years old, while the polonium rings in granite rocks, due to it's about 10^(-4)seconds half-life, reveal that the earth was formed instanteneously as a solid mass, otherwise, if liquid from The Big Bang, then the rings would be absent! Moreover, since the earth's magnetic field decays with a half-life of about 1,500yrs, then NO life would have been possible some 20,000yrs ago, thus, doing away with any possibility of evolution being the origin of our universe. This then leaves it to the only other option for its origin: SPECIAL CREATION by some Supreme Eternal Intelligence, whose faultless works, when mankind touches, eg, the ecosystem, man usually destroys for lack of knowing all the parameters involved, or even lack of power to handle them! May all His creation bring glory to Him throughout all ages. AMEN See more of this discussion:Our Universe's Likely Structure
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| Hot house earth or crustal shift | Posted by Peter |
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One recent study by Bornemann's team suggests that for a 200,000-year period around 91 million years ago, there were ice sheets at least half the size of the ones that blanket Antarctica today. The evidence comes from oxygen isotope ratios in shells from the Atlantic seabed (Science, vol 319, p 189).
However, a similar study by Wilson's team found no evidence of glaciation (Geology, vol 35, p 615), so this issue is far from settled. But if ice sheets can grow suddenly even during hothouse periods, Wilson point out, it means the climate can change more suddenly and dramatically than anyone thought. "That really demands being understood." Yet more evidence for crustal shift!See more of this discussion:Hot house earth or crustal shift
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| Hot house earth or crustal shift | Posted by Peter |
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In rocks from the late Cretaceous in Siberia, Robert Spicer of the Open University in Milton Keynes in the UK and his colleagues have found plenty of evidence for ferns and flowering plants, and even possibly the pollen of palm trees (Earth and Planetary Science Letters, vol 267, p 228). Their analysis suggests that at that time Siberia's mean annual temperature was about 13 °C, rarely touching freezing even in the winter months. "All the climate models give you very, very cold continental interiors [at high latitudes] in the winter time, so cold that you would certainly freeze palm trees and kill them off," Pierrehumbert says.
How about concluding that the land mass may not have been so near the pole at this time?See more of this discussion:Hot house earth or crustal shift
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| Hot house earth or crustal shift | Posted by Peter |
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on the Antarctic Peninsula, a finger of land that juts north towards South America, enough rock is exposed to give explorers a glimpse not just of Antarctica's ancient flora and fauna, but of the nature of the seas around it.
About 150 to 100 million years ago, the peninsula was a mountain range similar to the Andes, and its rivers drained into a massive basin, now called the James Ross basin. Over millions of years, the basin filled up with sediment and later the rocks it formed were uplifted. Today these rocks lie exposed on islands off the Antarctic Peninsula and contain a treasure trove of fossils from the Cretaceous, including silvery slivers of shells of ocean-dwelling ammonites and gastropods. In the late Antarctic summer, these fragments glint as they catch the sun which barely rises above the horizon. "It looks like the surface is covered in jewels," says palaeoclimatologist Jane Francis of the University of Leeds, UK, a veteran of 12 expeditions to the poles. Besides ammonites and gastropods, Francis and her colleagues have found abundant fossils of sea urchins and lobsters that lived on the sea floor, shark teeth, and even massive marine reptiles with rib bones about half a metre long. Oxygen isotopes in the shell fragments show that the waters around Antarctica 100 million years ago were a balmy 15 °C, compared with -2 to 0 °C today. Dinosaur bones, which must have been washed down off the peninsula into the sea, have also been found in the marine sediments (see "Dinosaurs at the poles"). Plant fossils unearthed by Francis and her students show that 100 million years ago the peninsula was lush with ferns and cycads, along with conifers resembling the monkey puzzle tree. Analysis of the shape and size of fossil leaves has led Francis to conclude that the peninsula was very warm during the mid-Cretaceous, with a mean annual temperature of about 17 to 19 °C, similar to that of South Africa today. "That's almost sub-tropical," says Francis. Sweltering greenhouse Growth rings in one fossil tree trunk suggest trees thrived despite complete darkness in mid-winter. "In tree-ring terms, the tree was very happy, it wasn't growing in any kind of stress, there's no sign of frost rings and there's no sign of drought," Francis says. New Scientist 21st June 2008 Surely the evidence is suggesting this land mass wasn't near the pole when these trees were growing!! Thriving trees in complete darkness?? How much evidence so you need before it hits you in the face?? These trees were not growing near the poles. They were growing in a tropical jungle near the equator!!See more of this discussion:Hot house earth or crustal shift
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| Hot house earth or crustal shift | Posted by Peter |
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In 2004 a team collected a core of sediment that had been deposited over tens of millions of years on the Lomonosov ridge, just 250 kilometres from the North Pole. One study of the core revealed that a freshwater fern called Azolla grew abundantly in the Arctic Ocean for 800,000 years about 50 million years ago (Nature, vol 441, p 606). At the time the Arctic Ocean was largely isolated from other oceans, and fresh water from rivers would have floated on top of denser salt water. "It might have been, at least in the surface waters, one of the biggest lakes on the planet," says Moran.
The waters of this mega-lake were a surprisingly warm 10 °C, but that's nothing to the temperatures reached a few million years earlier during the hottest part of the Eocene, when the ocean was salty. According to another study of the core the surface water 55 million years ago was around 18 °C, peaking at an incredible 23 °C - more than warm enough for a pleasant swim at the North Pole! New Scientist 21st June 2008 Yet more evidence for a crustal shift See more of this discussion:Hot house earth or crustal shift
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| Hot house earth or crustal shift | Posted by Peter |
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The most evocative image of a warm Arctic has emerged from the work of John Tarduno of the University of Rochester, New York. For more than a decade, Tarduno has been hunting for fossils on Axel Heiberg Island in the Canadian Arctic, just west of Greenland. The island was already well within the Arctic Circle 90 million years ago.
His team has found bones and even partial skeletons of a crocodile-like creature called a champsosaur from this period. The champsosaur was a fish-eating reptile up to 2.4 metres long that probably looked much like the gharials of India. Because these reptiles would have relied on their environment to stay warm, conditions in the far north must have been far hotter than today. "These fossils speak volumes," says palaeoclimatologist Paul Wilson of the University of Southampton in the UK. Last year, Tarduno's team reported that most champsosaur remains are of juveniles, meaning the animals not only lived but bred in the Arctic. As hatchlings and juveniles could not have survived if winter temperatures came anywhere close to freezing, this means it was not only warm, but warm all year round. Modern crocodiles are found no further north than the lower Yangtze and North Carolina. If the champsosaurs' temperature requirements were similar, the Axel Heiberg locality must have had mean annual temperatures of at least 14 °C, and the average temperature during the coldest month could not have fallen below 5.5 °C. The region would not even have had ice in winter. New Scientist 21st June 2008 Yet more evidence for crustal shift See more of this discussion:Hot house earth or crustal shift
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| Hot house earth or crustal shift | Posted by Peter |
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One of the earliest signs that the poles were ice-free and warm 100 million years ago was the discovery at the turn of the 20th century of fossil breadfruit trees from the Cretaceous in Greenland; today such trees are at home in places like Hawaii. Since then, even more extraordinary finds have been made.
Yet more evidence for crustal shift See more of this discussion:Hot house earth or crustal shift
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| BBC NEWS | Science/Nature | Fossils date Dry Valleys' origin | Posted by Peter |
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Once the north pole was infested with crocodiles while Antarctica was covered by lush forests. But if the poles were so balmy, what on earth were the tropics like?
WHEN Ernest Shackleton and his men marched towards the South Pole in December 1908, they came across something entirely unexpected. After scaling the vast Beardmore glacier on the edge of the polar plateau, they found seams of coal amid the snow and ice. They also found impressions of leaves in sandstone boulders nearby and even fossilised wood from a coniferous tree. The conclusion was extraordinary but inescapable: Antarctica was once warm and forested, conditions that could hardly be more different to the far-below-freezing midsummer weather that forced Shackleton's team to turn back before reaching the pole. How was this possible? Four years later, Alfred Wegener put forward his theory of continental drift which, it was later realised, could explain the balmy climate: Antarctica had been warmer because it was once much closer to the equator. Even today, some schoolchildren are taught that continental drift accounts for all the evidence for a warmer Antarctica. However, the fossil trees Shackleton's team discovered grew around 250 million years ago, when Antarctica was barely closer to the equator than it is today. What's more, the continent reached its current position roughly 100 million years ago, and an ever-growing list of fossil finds date from 100 to 40 million years ago. During this time, when dinosaurs roamed the almost subtropical forests of an ice-free Antarctic, conditions on the other side of the planet were even more remarkable: the Arctic Ocean was a gigantic freshwater lake infested with crocodile-like reptiles. New Scientist 21st June 2008 Crustal shift is a much better hypothesis to account for these observations See more of this discussion:BBC NEWS | Science/Nature | Fossils date Dry Valleys' origin
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| BBC NEWS | Science/Nature | Fossils date Dry Valleys' origin | Posted by |
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Notwithstanding the significance of the fossil preservation, the presence of lake ostracods at this latitude, 77 degrees South, is also of great note. With modern ostracod distribution, the most southerly ones are at about 60 degrees South."
McMurdo Dry Valleys (BBC) The team says the fossils therefore represent a precise marker, indicating the switch from conditions which one might see in Northern Canada and Iceland today, where summer warmth brings a melt, liquid water and a flourish of life - to the more severe, arid conditions we recognise in the Antarctic today. "This also helps us understand the whole evolution of Earth's climate system because you've got this huge climate jump that takes place about 14 million years ago when the oceans reorganise, Antarctica freezes over - a whole host of things change right at that point. "What we're doing with these ostracods is to say: 'that's it, that's the point'." The fossil research is detailed in the journal Proceedings of the Royal Society B. http://news.bbc.co.uk/1/hi/sci/tech/7519614.stm See more of this discussion:BBC NEWS | Science/Nature | Fossils date Dry Valleys' origin
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| Re: another paper on nuclear event in N.A | Posted by Sanka Chandima Abayawardena |
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Hey im Guy from Sri-Lanka who is coming from a family of Yak tribe (great king Ravana IS ALSO FROM OUR TRIB) .
These things you are discussing here are our folk tails. The story is about our lost Hela Asura Empire and our attempt to unify the huge empire around the capital Lanka Pura (today this lanka pura is known as Seegiriya the 8th wonder of the world.) If you come to Sri-Lanka and go to places where still the old inherit ants live in remote places of the country you may here some unbelievable stories. And one of the Vimana had survived the thought time till 1800's till some stupid British ruler destroyed it in its hideout. I recon you should contact Dr. Suriya Gunasekara who is scholar who knows many secrets. ejournalists -at- sltne.lk or +94-112861949 See more of this discussion:Re: another paper on nuclear event in N.A
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| Re: another paper on nuclear event in N.A | Posted by Peter |
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Interesting that this work has resurfaced again at the American Geophysical Union meeting in Acupulco, Mexico (reported in New Scientist Magazine. 26th May 2007)
Further analysis of the carbon layer in the sediment gives a date of 12900 years ago. The carbon layer includes nano diamonds, and an excess of helium 3. there is no excess of iridium or nickel suggesting it was not an asteroid impact. I find it difficult to accept that any airburst could deliver enough heat to melt two miles thick ice sheets - radiant energy would simply be reflected back off the surface, and a dust layer would be buried by the next winters snowfall. The craters of the Carolina bays do not contain any extra terrestrial material, and ice blocks would give the right profile. The helium 3 and nano diamonds would also support a nuclear explosion under the ice. Wild fires following the nuclear explosion could be responsible for wiping out the Clovis people and the 35 genera of the continents animals that went extinct. See more of this discussion:Re: another paper on nuclear event in N.A
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| Re: another paper on nuclear event in N.A | Posted by |
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TERRESTRIAL EVIDENCE OF A NUCLEAR CATASTROPHE IN PALEOINDIAN TIMES
[PDF version includes tables, figures, etc.] [updated response to post publication questions][.doc version] by Richard B. Firestone, Lawrence Berkeley National Laboratory, and William Topping, Consultant, Baldwin, Michigan THE PALEOINDIAN OCCUPATION of North America, theoretically the point of entry of the first people to the Americas, is traditionally assumed to have occurred within a short time span beginning at about 12,000 yr B.P. This is inconsistent with much older South American dates of around 32,000 yr B.P.1 and the similarity of the Paleoindian toolkit to Mousterian traditions that disappeared about 30,000 years ago.2 A pattern of unusually young radiocarbon dates in the Northeast has been noted by Bonnichsen and Will.3,4 Our research indicates that the entire Great Lakes region (and beyond) was subjected to particle bombardment and a catastrophic nuclear irradiation that produced secondary thermal neutrons from cosmic ray interactions. The neutrons produced unusually large quantities of 239 Pu and substantially altered the natural uranium abundance ratios ( 235 U/238 U) in artifacts and in other exposed materials including cherts, sediments, and the entire landscape. These neutrons necessarily transmuted residual nitrogen ( 14 N) in the dated charcoals to radiocarbon, thus explaining anomalous dates. The evidence from dated materials We investigated a cluster of especially young radiocarbon dates concentrated in the north-central area of North America. For example, at the Gainey site in Michigan a 2880 yr B.P. radio-carbon date was reported, while the thermoluminescence date for that site is 12,400 yr B.P.5 Other anomalous dates found at Leavitt in Michigan, 6 Zander and Thedford in Ontario,7 Potts in New York,8 Alton in Indiana, 9 and Grant Lake in Nunavut 10 are summarized in Table 1. The Grant Lake Paleoindian site is most remarkable because its 160 [rc] yr B.P. age is nearly contemporary, while adjacent and deeper samples give ages of 1480–3620 [rc] yr B.P. Stratigraphic associations place Paleoindian occupations at depth on the pre-historic North American landscape on sediments that form the old C horizon composed of parent material, Wisconsinan deposits that predate Holocene sediment buildup.11,12,13 The young Paleoindian dates cannot be correct, particularly since there are no patterned anomalies noted in later-period prehistoric assem-blages relating to higher stratigraphic positions. In a pioneering study of the Paleoindian site at Barnes, Michigan, Wright and Roosa observed that Paleoindian artifacts were deposited before the formation of spodosols ceased in this area about 10,000 yr B.P.14 This conclusion was based on observing that cemented sediments on artifacts, found outside their original context, defines their original stratigraphic position. The evidence from particle bombardment Sediment profiles were taken at Paleoindian sites and at numerous widely separated control locations in Michigan. The C sediment horizon is clearly recognized by its transitional color and confirmed by elevated concentrations of potassium and other isotopes. Color and chemistry are key indicators of this very old soil 11,12,13 derived from parent materials and associated postglacial runoff.15 At Gainey, large quantities of micrometeorite-like particles appear to be concentrated near the boundary between the B and C sediment horizons. They can be separated with a magnet and are identified by the presence of chondrules and by visual evidence of sintering and partial melting. These particles, dissimilar to common magnetites, are found in association with a high frequency of "spherules." The depth profiles for potassium and particles at the Gainey site are compared in Fig. 1. Minor vertical sorting of particles is apparent, with a shallow spike of particles near the surface probably resulting from modern agricultural or industrial activity. Total gamma-ray counting of sediment profiles in the various locations invariably showed increased radioactivity at the B-C boundary consistent with enhanced potassium ( 40 K) and possibly other activities. Microscopic examination of chert artifacts from several widely separated Paleoindian locations in North America revealed a high density of entrance wounds and particles at depths that are evidence of high-velocity particle bombardment. Chondrules were identified visually; their presence necessarily indicates heating during high-speed entry into the atmosphere. The depth of penetration into the artifacts implies that the particles entered with substantial energy.16 Field simulations with control cherts for large particles (100–200 microns) suggest an entrance velocity greater than 0.4 km/s, and experiments at the National Superconducting Cyclotron Laboratory indicate that the smaller particles left tracks comparable to about 526 MeV iron ions ( 56 Fe) in Gainey artifacts. Similar features are not observed in later-period prehistoric artifacts or in bedrock chert sources. Track angles were estimated visually; track densities were measured with a stage micrometer; track depths were found by adjusting the microscope focus through the track. These data are summarized in Table 1. Track and particle data in Table 1 suggest that the total track volume (density times depth) is highest at the Michigan, Illinois, and Indiana sites and decreases in all directions from this region, consistent with a widespread catastrophe concentrated over the Great Lakes region. The nearly vertical direction of the tracks left by particle impacts at most sites suggests they came from a distant source. The evidence from uranium and plutonium Natural uranium, which is ubiquitous in cherts, has a 235 U/238 U isotopic ratio of 0.72 percent, which varies by less than 0.1 percent in natural sources.17 Significant variations in the isotopic ratio do not occur because of chemical processes; however, a thermal neutron bombardment depletes 235 U and thus alters the ratio. Solar or galactic cosmic rays interacting with matter produce fast secondary neutrons that become thermalized by scattering from surrounding materials. Thermal neutrons see a target of large cross section (681 barns)A for destroying 235 U, compared with a target of only 2.68 barns for neutron capture on 238 U. Therefore, despite the low abundance of 235 U, about 1.8 times as many 235 U atoms are destroyed as 238 U atoms by thermal neutrons. If a large cosmic-ray bombardment impacted the earth and irradiated the prehistoric landscape with thermal neutrons, the 235 U/238 U ratio would be changed; 239 Pu would be produced from neutron capture on 238 U, followed by the decay of 239 U. Neutrons colliding with nitrogen (1.83 barns) would create 14 C in exactly the same way 14 C is normally produced in the upper atmosphere, necessarily resetting the radiocarbon dates of any organic materials lying near the surface on the North American prehistoric landscape—including charcoals at Paleoindian sites—to younger values. 239 Pu produced during the bombardment will also be partly destroyed by thermal neutrons with 1017 barn cross section. Assuming 239 Pu doesn’t mobilize, it will decay back to 235 U (half-life 24,110 yr), partially restoring the normal abundance. Paleoindian artifacts from Gainey, Leavitt, and Butler, and two later-period artifacts from the same geographic area of Michigan were analyzed for 235 U content by gamma-ray counting at the Phoenix Memorial Laboratory, University of Michigan. They were compared with identical chert types representative of the source materials for the artifacts. Control samples were extracted from the inner core of the purest chert known to be utilized by prehistoric people. The Paleoindian artifacts contained about 78 percent as much 235 U as the controls and later-period artifacts, suggesting substantial depletion. Depletion of 235 U necessarily indicates that thermal neutrons impacted these artifacts and the surrounding prehistoric landscape. Various artifacts, cherts, sediments, and a control sample containing about 0.2 percent uranium obtained from uraninite were sent to the McMaster University Centre for Neutron Activation Analysis to determine 235 U concentration by delayed neutron counting and 238 U concentration by activation analysis. These results are shown in Table 2. The 235 U/238 U ratios for all samples except the control deviated substantially from the expected ratio. McMaster ran additional calibration standards and has considerable expertise analyzing low-level uranium. This analysis was sensitive to a few ppb for 235 U and 0.1–0.3 ppm for 238 U, more than sufficient to precisely analyze the uranium-rich chert samples (0.7–163.5 ppm). Most samples were depleted in 235 U, depletion increasing geographically from the southwest (Baker, Chuska chert, 17 percent) to the northeast (Upper Mercer, 77 percent), as shown in Table 2. This is consistent with cosmic rays focused towards northern latitudes by Earth’s magnetic field. Only a very large thermal neutron flux, greater than 10^20 n/cm 2 , could have depleted 235 U at all locations. Samples of unaltered flakes from Taylor and sediment originally adjacent to Gainey artifacts showed 235 U enriched by 30 percent. Both samples were closely associated with the particles described above. The position of these samples appears to be related to the enrichment, which cannot be explained by thermal neutrons from the bombardment. To test this, we bathed another Taylor flake in 48-percent HF at 60°F for ten minutes to remove the outer 70 percent of the sample and the attached particles. Analysis showed the "inner" flake depleted in 235 U by 20 percent, consistent with the other depleted cherts. Samples of Gainey sediment and Taylor flakes were analyzed for plutonium by Nuclear Technology Services, Inc., of Roswell, Georgia, which specializes in radiochemistry using standard methodology. The plutonium, with an aliquot of NIST-traceable 242 Pu added, was chemically separated on an anion exchange resin column and counted on an alpha-particle spectrometer. The 239 Pu/238 U ratios in both samples were approximately 10 ppb, vastly exceeding the expected ratio of 0.003 ppb.18 The results of this analysis are shown in Table 2. Chert is a glass-like material highly impervious to penetration by any nuclear fallout that might also contribute 239 Pu. We analyzed a long-exposed piece of Bayport chert by gamma-ray counting at the LBNL low-background facility for the presence of cesium-137 ( 137 Cs), a key indicator of fallout (from nuclear testing), and found none. The B-C interface typically lies sufficiently deep that contamination by fallout is improbable. It is important to note that fallout cannot explain the depletion of 235 U. Since the depletion of 235 U must have resulted from bombardment by thermal neutrons, the presence of 239 Pu from irradiation of 238 U is expected. The total thermal neutron flux required to produce the observed 239 Pu concentration can be cal-culated from the relative concentrations of 239 Pu (corrected for the decay) and 238 U, and the thermal neutron–capture cross section for 238 U. This neutron flux can then be used to estimate the amount of additional 14 C that would have been produced in charcoal by neutrons colliding with 14 N ( 14 N cross section = 1.83 barns). The corrected radiocarbon age can then be estimated by comparing the current amount of 14 C in the dated char-coals, determined from their measured radiocarbon age, with the amount of 14 C that would have been produced by the bombardment. For these calculations we assume that charcoal contains 0.05 per-cent residual nitrogen 19 and that initial 14 C concentrations were the same as to-day (one 14 C atom for 10^12 12 C atoms). We derive a thermal neutron flux of c. 10^17 n/cm 2 at Gainey, which corresponds to an approximate date of 39,000 yr B.P. No radiocarbon date is available for the more southerly Taylor site, but for the conventional range of accepted Paleoindian dates the neutron flux would be c. 10^16 n/cm 2 , giving a date of about 40,000 yr B.P. These calculations necessarily neglect differences in the neutron flux experienced by the dated charcoal and the artifacts, the effects of residual 239 Pu from previous bombardments, and loss of 239 Pu due to leaching from chert over time. The neutron flux calculated from the 235 U/238 U ratio is more than 1000 times that implied by the level of 239 Pu. Since 239 Pu decays to 235 U, partly restoring the natural abundance, it appears that substantial quantities of 239 Pu have migrated out of the chert. This mobility is demonstrated at the Nevada Test Site, where plutonium, produced in nuclear tests con-ducted by the U.S. between 1956 and 1992, migrated 1.3 km.20 It has also been shown that atoms produced by radioactive decay or nuclear reaction become weakly bound to the parent material and pass more readily into solution than isotopes not affected.21 Both 239 Pu and 235 U are thus expected to be mobile, complicating any analysis. This is consistent with the enrichment of 235 U in the two external samples where migrating 239 Pu or 235 U may have been trapped, thus enriching the relatively uranium-poor outer regions. Alternatively, excess 235 U may have been carried in by the particles. Radiocarbon produced in situ by irradiation should also be mobile. If 14 C is more mobile than 239 Pu, then the dates calculated above should be decreased accordingly. Redating North American sites The 39,000 yr B.P. date proposed for the Gainey site is consistent with the prevailing opinion among many archaeologists about when the Americas were populated. It is also commensurate with dates for South American sites and with a Mousterian toolkit tradition that many see as the Paleoindian precursor. The proposed date for the Gainey site also falls closer in line with the radiocarbon date for a Lewisville, Texas, Paleoindian site of 26,610 ± 300 yr B.P.22,23 and radio-carbon dates as early as c. 20,000 yr B.P. for Meadowcroft Rockshelter.24 Since the Lewisville and Meadowcroft sites were likely exposed at the same time to ther-mal neutrons, we estimate that their dates should be reset to c. 55,000 yr B.P. and c. 45,000 yr B.P., respectively. It is likely that Paleoindians occupied low latitudes during the full glacial and migrated to more northerly areas as the ice front retreated. Therefore the pat-tern of dates makes sense from the archaeologist’s point of view. Dates for North American sites should generally be reset by up to 40,000 years, depending on latitude and overburden. Geologists believe that before c. 15,000 yr B.P. the Wisconsinan glaciation covered the more northerly locations where Paleoindian sites have been found.25 The ice sheet would have shielded the landscape and any artifacts from an irradiation. (The Gainey thermoluminescence date of 12,400 yr B.P. is probably a result of the heat generated by the nuclear bombardment at that time, which would have reset the TL index to zero.) The modified dates for Paleoindian settlements suggest that the timetable for glacial advance sequences, strongly driven by conventional radiocarbon dates, should be revisited in light of the evidence presented here of much older occupations than previously thought." The evidence from tree rings and marine sediments A large nuclear bombardment should have left evidence elsewhere in the radio- carbon record. It is well known that radiocarbon dates are increasingly too young as we go back in time. The global Carbon Cycle suggests that 14 C produced by cosmic rays would be rapidly dispersed in the large carbon reservoirs in the atmosphere, land, and oceans.26 We would expect to see a sudden increase in radiocarbon in the atmosphere that would be incorporated into plants and animals soon after the irradiation; after only a few years, most of the radiocarbon would move into the ocean reservoirs. The 14 C level in the fossil record would reset to a higher value. The excess global radiocarbon would then decay with a half-life of 5730 years, which should be seen in the radiocarbon analysis of varved systems. Fig. 2 plots 14 C from the INTCAL98 radiocarbon age calibration data of Stuiver et al. for 15,000–0 yr B.P.27 and Icelandic marine sediment 14 C data measured by Voelker et al. for 50,000–11,000 yr B.P.28 Excess 14 C is indicated by the difference between the reported radiocarbon dates and actual dates. Sharp increases in 14 C are apparent in the marine data at 40,000–43,000, 32,000–34,000 and c. 12,000 yr B.P These increases are coincident with geomagnetic excursions B that occurred at about 12,000 (Gothenburg), 32,000 (Mono Lake), and 43,000 yr B.P. (Laschamp),29 when the reduced magnetic field would have made Earth especially vulnerable to cosmic ray bombardment. The interstitial radiocarbon data following the three excursions were numerically fit, assuming exponential decay plus a constant cosmic ray–produced component. The fitted half-lives of 5750 yr (37,000–34,000 yr B.P.), 6020 yr (32,000–16,000 yr B.P.), and 6120 yr (12,000–0 yr B.P.) are in good agreement with the expected value. We also determined that contemporary radiocarbon contains about 7 percent residual 14 C left over from the catastrophe. The constant cosmic ray production rate was about 34 percent higher for the Icelandic sediment than the INTCAL98 samples, perhaps implying higher cosmic ray rates farther north. Disregarding fluctuations in the data from variations in ocean temperatures and currents, the results are clearly consistent with the decay of radiocarbon following the three geomagnetic excursions. In Fig. 2, the sharp drop in 14 C activity before 41,000 yr B.P. suggests that global radiocarbon increased by about 45 percent at that time and by about 20 percent at 33,000 and 12,000 yr B.P The results are remarkably consistent with Vogel’s comparison of 14 C and U-Th dates of a stalagmite that indicates global radiocarbon increased about 75 percent from 30,000 to 40,000 yr B.P. and about 30 percent around 18,000 yr B.P.30 McHargue et al. found high levels of 10 Be in Gulf of California marine sediments at 32,000 and 43,000 yr B.P.C that could not be explained by magnetic reversal alone and were attributed to cosmic rays, possibly from a supernova.29 The geomagnetic excursion at 12,500 yr B.P. coincides with the thermoluminescence date from Gainey, and additional evidence for a cosmic ray bombardment at that time is found in the increases of 10 Be,31 Ca,32 and Mg 32 in Greenland ice cores around 12,500 yr B.P. Similar increases are also seen in the data for NO 3 – , SO 4 – , Mg + , Cl – , K + , and Na + ions in Greenland ice cores.33 This occurrence can be dated precisely to 12,500 ± 500 yr B.P., an average of the remarkably consistent concentration peak centroids in the Greenland ice core data. Significant increases at that time are not found in comparable data for the Antarctic, which indicates that the cosmic ray irradiation was centered in the Northern Hemisphere. Weak evidence of an occurrence at 12,500 yr B.P. is seen in the radiocarbon record for marine sediments near Venezuela,34 confirming that the cosmic ray bombardment was most severe in northern latitudes. Lunar cosmogenic data also show evidence of increased solar cosmic ray activity at or before 20,000 yr B.P.35,36 although these data are not sensitive to earlier irradiation. The effect of a supernova on Earth Sonett suggests that a single supernova would produce two or three shock waves, an initial forward shock and a pair of reverse shocks from the initial expansion and a reflected wave from the shell boundary of a more ancient supernova.39,40 Fig. 2 shows that each episode in a series produced a similar amount of atmospheric radiocarbon. The sun lies almost exactly in the center 41 of the Local Bubble, believed to be the result of a past nearby supernova event. A candidate for the reverse shock wave is the supernova remnant North Polar Spur, with an estimated age of 75,000 years and a distance of 130 ± 75 parsecs (424 light years),42 conveniently located in the north sky from where it would have preferentially irradiated the Northern Hemisphere. Assuming the Taylor flux is average and 1,000 neutrons are produced per erg of gamma-ray energy,43 the catastrophe would have released about 10^16 erg/cm 2 (2 x 10^8 cal/cm 2 ), corresponding to a solar flare of 10^43 ergs or a gamma-flash of 10^54 ergs from a supernova about 1 parsec away. The geographical distribution of particle tracks, 235 U depletion, and 239 Pu concentration shown in Fig. 3 are quite consistent, although the particle tracks seem to be confined to a smaller geographic area. They indicate energy released over the northeastern sector of the U.S., with maximum energy at about 43° N, 85° W, the Michigan area of the Great Lakes region. A history of suspected cosmic cataclysms over the ages Wdowczyk and Wolfendale 44 and Zook 36 propose, based on the existing record of solar flare intensities, that solar flares as large as 3 x 10^38 ergs should be expected every 100,000 years. Clark et al. estimate that supernovas release 10^47 –10^50 ergs within 10 parsecs of Earth every 100 million years.45 Brackenridge suggests that a supernova impacted the earth in Paleoindian times.46 Damon et al. report evidence from the 14 C tree ring record that SN1006, which occurred at a distance of 1300 par-secs, produced a neutron shower of 2 x 10^8 n/cm 2 . 47 Castagnoli et al. report evidence of the past six nearby supernovae from the thermoluminescence record of Tyrrhenian sea sediments.48 Dar et al. suggest that a cosmic ray jet within 1000 parsec would produce 10^12 muons/cm 2 (greater than 3 x 10^9 eV) and 10^10 protons and neutrons/cm 2 (greater than 10^6 eV) and deposit over 10^12 erg/cm 2 in the atmosphere every 100 million years.49 A cosmic ray jet is also predicted to produce heavy elements via the r-process and could be a source of 235 U enriched up to 60 percent in uranium. The Paleoindian catastrophe was large by standards of all suspected cosmic occurrences. Normal geomagnetic conditions would focus cosmic rays towards the magnetic poles, concentrating their severity in those regions. However, low magnetic field intensity during a geomagnetic excursion may have allowed excessive cosmic rays to strike northeastern North America. (Whether the geomagnetic excursion admitted cosmic radiation, or the radiation caused the excursion, is uncertain. Given our present state of knowledge, cause and effect in this instance are unclear.) The presence of a nearby small and dense interstellar cloud may explain the origin of the particle bombardment.50 The size of the initial catastrophe may be too large for a solar flare, but a sufficiently powerful nearby supernova or cosmic ray jet could account for it. It appears that the catastrophe initiated a sequence of events that may have included solar flares, impacts, and secondary cosmic ray bombardments. A devastating effect on Earth The enormous energy released by the catastrophe at 12,500 yr B.P. could have heated the atmosphere to over 1000°C over Michigan, and the neutron flux at more northern locations would have melted considerable glacial ice. Radiation effects on plants and animals exposed to the cosmic rays would have been lethal, comparable to being irradiated in a 5-megawatt reactor more than 100 seconds. The overall pattern of the catastrophe matches the pattern of mass extinction before Holocene times. The Western Hemisphere was more affected than the Eastern, North America more than South America, and eastern North America more than western North America.51,52,53 Extinction in the Great Lakes area was more rapid and pronounced than elsewhere. Larger animals were more affected than smaller ones, a pattern that conforms to the expectation that radiation exposure affects large bodies more than smaller ones.54,55 Sharp fluctuations of 14 C in the Icelandic marine sediments at each geomagnetic excursion are interesting; because global carbon deposits in the ocean sediments at a rate of only about 0.0005 percent a year, a sudden increase in sediment 14 C may reflect the rapid die-off of organisms that incorporated radiocarbon shortly after bombardment. Massive radiation would be expected to cause major mutations in plant life. Maize probably evolved by macro-mutation at that time,55,56 and plant domestication of possibly mutated forms appears worldwide after the Late Glacial period. For example, there was a rapid transition from wild to domesticated grains in the Near East after the catastrophe.57 Implications for future study Much of what we assume about the Paleoindian period and the peopling of the Americas has been inferred from conventional radiocarbon chronology, which often conflicts with archaeological evidence. This work mandates that conventional radio-carbon dates be reinterpreted in light of hard terrestrial evidence of exposure of the radiocarbon samples to a cosmological catastrophe that affected vast areas of North America and beyond. A nuclear catastrophe can reset a group of unrelated artifacts to a common younger date, creating gaps and false episodes in the fossil record. Geographical variation and complicated overburdens may further confuse the interpretation. Scrutiny of Paleoindian artifacts and the North American paleolandscape, associated stratigraphic sediments, coupled with continued radiological investigations, may provide more evidence for the cosmic catastrophe and new clues to the origin of Paleoindians. How to contact the principals in this article: Richard B. Firestone e-mail: rbf@lbl.gov William H. Topping P.O. Box 62 Baldwin, MI. 49304 USA Acknowledgments This paper results from dissertation research that began in 1990, most recently funded by a National Science Foundation Physics Division, by William Topping. Support of Richard Firestone by the Director, Office of Energy Research, Division of Nuclear Physics, of the Office of High Energy and Nuclear Physics of the U.S. Department of Energy is greatly appreciated. The contributions of particular individuals over the years have been invaluable. Tony Baker, Kurt Carr, Chris Ellis, Mima Kapches, Ronald Lesher, Donald B. Simons, James Taylor, Curtis Tomak, John Tomenchuk, and Henry Wright in particular should be thanked for their contributions of artifacts which provided essential information. Alan Smith contributed important experimental data for this paper. We particularly acknowledge the participation of the Royal Ontario Museum and the Smithsonian Institution. In addition, there have been many invaluable contributions of time, analysis, and commentary by physicists, archaeologists, and geologists from the National Superconducting Cyclotron Laboratory at Michigan State University, Phoenix Memorial Laboratory and the Department of Physics at the University of Michigan, Departments of Anthropology and Geology at Wayne State University, Department of Physics at Washington University in St. Louis, Museum of Anthropology at the University of Michigan, Department of Physics at the University of Arizona, Harvard Cyclotron at Harvard University, Oak Ridge National Laboratory, Los Alamos National Laboratory, Johnson Space Center, the State University of Pennsylvania, Lawrence Livermore National Laboratory, and the Lawrence Berkeley National Laboratory. References 1 Gruhn, R., in Clovis: Origins and Adaptations, R. Bonnichsen, K. L. Turnmire, eds. (Oregon State University Press, Corvallis, 1991), pp. 283–286. 2 Muller-Beck, H., Science 152, 1191 (1985). 3 Bonnichsen, R., in Clovis: Origins and Adaptations, R. Bonnichsen, K. L. Turnmire, eds. (Oregon State University Press, Corvallis , 1991), pp. 309–329. 4 Bonnichsen, R., F. Will, in Ice Age Peoples of North America, R. Bonnichsen, K. L. Turnmire, eds. (Oregon State University Press, Corvallis, 1999), pp. 395–415. 5 Simons, D. B., M. J. Shott, H. T. Wright, Arch. East. Nor. Amer. 12, 266 (1984). 6 Shott, M.J., The Leavitt Site (Museum of Anthropology, Ann Arbor, 1993). 7 Stewart, A., Ontario Arch. 41, 45 (1984). 8 Gramly, R. M., J. Lothrop, Arch. East. Nor. Amer. 12, 1222 (1984). 9 Tomak, C. H., Dancey Ohio Arch. Coun., Columbus, 117 (1994). 10 Wright, J. V., Borden Number Kkln-2, Lab No. S-833. Canadian Archaeology Associa-tion C14 Database Search, http://www.canadianarchaeology.com/localc14/c14search.htm . 11 S. Boggs, S., Principles of Sedimentology and Stratigraphy (MacMillan, New York, 1987). 12 Easterbrook, D. J., Surface Processes and Landforms (MacMillan, New York, 1993). 13 Birkeland, P. W., Soils and Geomorphology (Oxford University Press, New York, 1984). 14 Wright, H. T., W. B. Roosa, American Antiquity 31, 850 (1966). 15 Turner, M. D., E. J. Zeller, G. A. Dreschoff, J. C. Turner, in Ice Age Peoples of North America, R. Bonnichsen, K. L. Turnmire, eds. (Oregon State University Press, Corvallis, 1999), pp. 42–77. 16 Firestone, R. B., W. Topping, Paleoindian Nuclear Event, http://ie.lbl.gov/Paleo/paleo.html . 17 Kuroda, P. K., The Origin of the Chemical Elements, (Springer-Verlag, Berlin Heidelberg, 1982). 18 Seaborg, G. T., W. D. Loveland, The Elements beyond Uranium, (John Wiley & Sons, Inc., New York, 1990). 19 Ostrom, N., analysis at Michigan State University of charcoal and wood dated at 2800 and 42,000 yr B.P. respectively, private communication. 20 Kersting, A. B., et al., Nature 397, 56 (1999). 21 Cherdyntsev, V. V., Abundance of Chemical Elements. (The University of Chicago Press, Chicago, translated by W. Nichiporuk, 1961). 22 Wormington, H. M., Ancient Man in North America, (The Denver Museum of Natural History, Denver, 1957). 23 Shirley, R. H., et al., Environmental Geology Notes 109, 1985. 24 Adovasio, J. M., R. C. Carlisle, Science 239, 713 (1988). 25 Farrand, W. R., The Glacial Lakes around Michigan, Bulletin 4. (Geological Survey Division, Michigan Department of Environmental Quality, 1988). http://www.deq.state.mi.us/gsd/Gltext.html . 26 Schimel, D. S., et al., in Climate Change 1994. Radiative Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, J. T. Houghton, L. G. M. Filho, J. Bruce, H. Lee, B. A. Callander, E. Haites, N. Harris, and K. Maskell, eds. (IPCC Report. Cambridge University Press, Cambridge, 1994). 27 Stuiver, M., et al., Radiocarbon 40, 1041 (1998). 28 Voelker, A. H. L., et al., Radiocarbon 40, 517 (1998). 29 McHargue, L. R., P. E. Damon, D. J. Donahue, Geophys. Res. Lett. 22, 659 (1995). 30 Vogel, J. C., Radiocarbon 25, 213 (1983). 31 Finkel, R. C., K. Nishiizumi, J. Geophys. Res. 102, 26699 (1997). 32 De Angelis, M., J. P. Steffensen, M. R. Legrand, H. B. Clausen, C. U. Hammer, Journal of Geophysical Research 102, 26681 (1997). 33 Mayewski, P. A., et al., Journal of Geophysical Research 102, 26345 (1997). 34 Hughen, K. A., et al., Radiocarbon 39, 483 (1998). 35 Jull, A. T., et al., Geochimica et Cosmochimica Acta 62, 3025 (1998). 36 Zook, H. A., Proc. Conf. Ancient Sun, J. A. Eddy, R. Merrill, eds., 245 (1980). 37 Prouty, W. F., Geol. Soc. Am. Bull. 63, 167 (1952). 38 Eyton, J. R., J. L. Parkhurst, A Re-Evaluation of the Extraterrestrial Origin of the Carolina Bays, http://abob.libs.uga.edu/bobk/cbayint.html (1975). 39 Sonett, C. P., G. E. Morfill, J. R. Jokipii, Nature 330, 458 (1987). 40 Sonett, C. P., Radiocarbon 34, 239 (1992). 41 Davelaar, J., J. A. M. Bleeker, A. J. M. Deerenberg, Astron. Astrophys. 92, 231 (1980). 42 Lingenfelter, R. E., R. Ramaty, in Radiocarbon Variations and Absolute Chronology, I. U. Olson, ed. (John Wiley & Sons, New York, 1970), pp. 513–537. 43 Wdowczyk, J., A.W. Wolfendale, Nature 268, 510 (1977). 44 Clark, D. H., W. H. McCrea, F. R. Stephenson, Nature 265, 318 (1977). 45 Brackenridge, G. R., Icarus 46, 81 (1981). 46 Damon, P. E., D., Kaimei, G. E. Kocharov, J. B. Mikheeva, A. N. Peristykh, Radiocarbon 37, 599 (1995). 47 Castagnoli, G. C., G. Bonino, and S. Miono, Nuovo Cimento 5C, 488 (1982). 48 Dar, A., A. Laor, N. J. Shaviv, Phys. Rev. Lett. 80, 5813 (1998). 49 Frisch, P. C., American Scientist 88 (2000). 50 Guilday, J. E., P. S. Martin, Pleistocene Extinctions, the Search for a Cause, P. S. Martin, H. E. Wright, eds. (Yale University Press, New Haven,1967) pp. 5–120. 51 Meltzer, D. J., T. I. Mead, Quat. Res. 19, 130 (1983). 52 Robinson, A., Earth Shock (Thames and Hudson, Ltd, London, 1993). 53 Farrand, W. R., Science 133, 729 (1961). 54 Sanderson, I. T., Sat. Evening Post 232, 82 (1960). 55 Iltis, H. H., Science 222, 886 (1983). 56 Benz, F. F., H.H. Iltis, Amer. Antiq. 55, 500 (1990). 57 Murray, J., The First European Agriculture (Edinburgh University Press, Edinburgh, (1970). See more of this discussion:Re: another paper on nuclear event in N.A
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| Gamburtsev Subglacial Mountains | Posted by Peter |
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A range of mountains have been detected under the ice of Antarctica where no range of mountains was expected. Conventional geological theory cannot explain their existence. Gamburtsev Subglacial Mountains
I predict that when these mountains are mapped in detail they will not show a surface eroded by a moving ice sheet, but will show a jumbled mass of sharp edged rock blocks kilometers wide with sharp cliffs, deep fissures and rock thrust over ice. These features should be preserved where there is little flow of the ice. This would be evidence of rapid fissuring and thrusting of the crust during an overturn. See more of this discussion:Gamburtsev Subglacial Mountains
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| Re: Magnitude of shift over-estimated | Posted by Peter |
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There are two mechanisms for maintaining the balance of the crust as the ice melts.
The crust can rise as the ice melts. For example the crust under scotland is thought to be still rising after losing the ice of the last ice age - which suggests that this can only compensate for slow melting taking tens of thousands of years. The only other mechanism is movement of the crust itself. This need to redistribute crustal mass is what I think drives continental drift. The big question is how much pressure to move the continental plates will result in only sporadic earthquakes - the huge Indonesian earthquake that caused the big tsunami moved a large chunk of crust and was enough to re-align the axis of the rotation very slightly - and how much pressure is needed before an earthquake like that triggers a cascade of earthquakes that results in overturn. My guess is that serious rapid melting of Greenland or Antarctica taking less than a thousand years could trigger overturn. See more of this discussion:Re: Magnitude of shift over-estimated
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| Time involved | Posted by Peter |
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Hi Peter,
You say that the rapid melting of the polar ice will throw the earths axis off ballance, how fast will the ice caps need to melt for a overturn to occur, and how fast can the crust reshift to correct the im-ballance? Thanks Peter See more of this discussion:Time involved
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