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Evidence of high cosmic dust concentrations in late Pleistocene polar ice (20,000-14,000 years BP)

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The cosmic dust concentration in the solar system during the last ice age was investigated by means of eight samples from 1215-1279 m depth in the Camp Century ice core. Neutron activation analysis was applied to measure the Ir and Ni concentrations. The study was carried out to test the hypothesis that sudden cosmic dust enrichments in the solar system may have attenuated sunlight sufficiently to cause the ice ages. The cosmic dust concentrations were compared to concentrations up in ocean core samples from the same epoch. The data indicate that five instances of several orders of magnitude increases in the cosmic dust abundance occurred during the period 20,000-14,000 BP. The particles were small enough to have caused, in dispersion, significant alterations in the amount of sunlight reaching the earth.
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
1985Metic..20..545L
... These include the cosmic dust indicators Ir, Ni, and Au, as well as Fe, Co, Ag, Sn, Sb, Ba, Sc, Cs, La, Ce, Tb, and Hf. These measurements had been previously documented (LaViolette, 1983a) and summarized (LaViolette, 1983b); also see LaViolette (1985).* In addition, new results of EDS analysis and SEM imaging are reported here for both tin-rich Camp Century ice core samples donated by Thompson (G962-1 and G1038-1). ...
... Eight Camp Century ice core dust samples spanning depths 1212 to 1275 meters (40.2 -74.7 kyrs BP), were analyzed. Five of these had been donated by L. Thompson who had filtered them in a class 100 clean room at Ohio State University as part of his earlier microparticle _____________________ * Ages previously reported for these eight samples (LaViolette, 1983a(LaViolette, , 1983b(LaViolette, , 1985 were overly young and have been here substantially revised by correlating the Camp Century oxygen isotope profile with the more recent and better dated GISP2 Greenland ice core isotope profile with additional corrections applied to bring the dating into correspondence with the Cariaco Basin-Hulu speliotherm chronology (Wenninger, 2007). Also the sample depths in the present paper are more correctly given as actual core depths whereas drilling log book depths had been previously published for these samples which were greater by 3 to 4 meters. ...
... This influx rate is about 1.7 X 10 4 times higher than the current cosmic dust deposition rate onto the Antarctic ice sheet of 60 ng/cm 2 /yr inferred from the nickel concentration measurements of Hanappe et al (1968), or about 4.5 X 10 5 times higher if referenced to the value of 2.2 ng/cm 2 /yr, determined by Takaheshi (1978) from iridium measurements made on ice from Dome C. The elevated Ir and Ni deposition rates found in five of the other Camp Century ice core samples exhibited lesser enhancements amounting to a one to two orders of magnitude increase relative to current extraterrestrial dust deposition rates (LaViolette, 1985). ...
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This paper presents evidence of the first detection of interstellar dust in ice age polar ice. Neutron activation analysis (NAA) results are reported for 15 elements found in dust filtered from eight samples of Camp Century Greenland ice dating from 40 to 78 kyrs BP. High concentrations of Sn, Sb, Au, Ag, Ir, and Ni were found to be present in three out of these eight samples. One compositionally anomalous dust sample from an ice core depth of 1230.5 meters (age ~49 kyrs BP, near the beginning of D/O stadial No. 13) was found to contain tin with an average weight percent of 49% as determined by energy dispersive x-ray analysis (EDS). This sample was also found to contain high concentrations of Pb with an average weight abundance of 8.4% and matching the Sn:Pb ratio observed in interstellar spectra. Dust particles in this sample generally have a platy morphology and range from submicron size up to a size as large as 120 μm, a particle consisting almost entirely of SnO2 and being the largest monomineralic extraterrestrial dust particle so far discovered. One porous aggregate tin-bearing particle was found to contain nanometer sized chondrules indicating an extraterrestrial origin. The extraterrestrial origin for the tin is also indicated by the presence of isotopic anomalies in the 114Sn, 115Sn and 117Sn isotopes. Follow up isotopic measurements of this tin-rich dust need to be performed to improve confidence in the anomalies reported here. High abundances of the low melting point elements Ag, Au, and Sb are also present in this tin-rich sample along with elevated abundances of the siderophiles Ir, Ni, Fe, and Co, the latter being present in chondritic proportions and indicating that about 9% of the dust has a C1 chondrite component. Measurements indicate that about 97% of this dust is of extraterrestrial origin with a 3% residual being composed of terrestrial wind blown dust. EDS analysis of another tin-rich Camp Century ice core dust sample dating to ~130 kyrs BP was found to contain tin-rich particles with a similar platy morphology and to have Sn and Pb weight abundances averaging 39% and 7.5% respectively, again approximating the interstellar Sn:Pb ratio. The relative absence of cosmic microspheres and the unmelted appearance of the tin-rich particles in both of these samples suggests that these particles entered the Earth's atmosphere at low velocity, implicating a gradual accumulation of dust from a dispersed state in the near Earth space environment. The unusual enhancement of Sn and Pb could be explained if these dust particles were originally present in the solar system's interstellar environment in a superconducting native metal state and were preferentially concentrated through Meissner effect forces by the passage of cosmic ray driven hydromagnetic shocks which may also have transported them into the solar system. The 49 kyrs BP event is estimated to have lasted over 6 years and to have deposited dust onto the Earth at a rate 104 - 105 times higher than present rates. This had a significant cooling effect on climate and resulted in a transient 33 fold increase in snow accumulation. Future discovery of this event in ice cores at other locations should void any lingering thoughts that this heavy metal enhancement may be due to sample contamination.
... These findings were subsequently presented at scientific conferences and published in refereed scientific journals. (2)(3)(4)(9)(10) Numerous predictions made by this Ph.D. study were later verified (see http://www.etheric.com/LaViolette/Predict.html). By 1997, I had published a book about this phenomenon entitled Earth Under Fire (http://www.etheric.com/LaVioletteBooks/Book-EUF.html). ...
... Analysis of Greenland ice has shown that, in fact, the solar system was filled with large concentrations of cosmic dust during the last ice age. (10) As this nebular material entered the inner solar system, it would scatter sunlight so that a portion of our radiation would come from a uniform glow filling both the daytime and night time sky. If you have had the experience of looking at the tail of a comet through a pair of binoculars, then just imagine that same diffuse glow filling the entire sky and blotting out the stars. ...
... All of these effects together would dramatically affect the Earth's climate. (1)(2)(3)(4)(9)(10) On some occasions the invading cosmic dust could produce a prolonged cold spell or even initiate an ice age if one was not already in progress; at other times it could produce a period of excessive warmth which could terminate an existing ice age or produce a brief interstadial. The geologic record reveals that our planet has been plagued by ice ages for most of the past several million years. ...
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Comets and asteroids are not the only space hazard that threatens the Earth. There is another phenomenon that occurs far more frequently but that has only recently been discovered—the arrival of an intense volley of Galactic cosmic rays, or what is termed a Galactic superwave. (1-4) The most recent time that a major superwave affected the Earth, and the entire solar system, was during the period from about 16,000 to 11,000 years ago. Through its ultimate energizing effect on the Sun, it was responsible for bringing an end to the last ice age.
... In LaViolette (1985) there is evidence that cosmic dust concentrations where two orders of magnitude greater in the last glacial age than they are nowadays. It is stated that this high concentration of cosmic dust during the last ice age, should have changed the light transmitting properties of our solar system. ...
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Solar wind is an infinite oscillation, the result of Earth-Venus orbital resonance. Solar wind variations show in climate data series and accurately predict climate variations. As solar wind drives away cosmic dust, it makes the Sun shine brighter, warming Earth.
... Figuring the interplanetary dust concentration to be on the order of 2 × 10 -22 g/cm 3 , the sheath's dust mass concentration may currently reach 10 -17 g/cm 3 , with 10 13 g being present in the inner portion of the cloud within 10 5 km (15 earth radii) of the Earth's surface. If solar system cosmic dust concentrations were substantially higher at the end of the last ice age (LaViolette 1983(LaViolette , 1985(LaViolette , 2005, this potential cosmic dust source could have amounted to as much as 10 15 g. ...
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The hypothesis is presented that an abrupt rise in atmospheric radiocarbon concentration evident in the Cariaco Basin varve record at 12,837 ± 10 cal yr BP, contemporaneous with the Rancholabrean termination, may have been produced by a super-sized solar proton event (SPE) having a fluence of ~1.3 × 10 11 protons/cm 2 . A SPE of this magnitude would have been large enough to deliver a lethal radiation dose of at least 3–6 Sv to the Earth's surface, and hence could have been a principal cause of the final termination of the Pleistocene megafauna and several genera of smaller mammals and birds. The event time-correlates with a large-magnitude acidity spike found at 1708.65 m in the GISP2 Greenland ice record, which is associated with high NO -3 ion concentrations and a rapid rise in 10 Be deposition rate, all of which are indicators of a sudden cosmicray influx. The depletion of nitrate ions within this acidic ice layer suggests that the snowpack surface at that time was exposed to intense UV for a prolonged period, which is consistent with a temporary destruction of the polar ozone layer by solar cosmic rays. The acidity event also coincides with a large-magnitude, abrupt climatic excursion and is associated with elevated ammonium ion concentrations, an indicator of global fires.
... The results of this research proved to support this hypothesis (LaViolette, 1983). A check of the geologic record indicated that at the end of the last ice age, 16,000 to 11,000 years ago, and on other past occasions, the Earth did have a prolonged increase in its beryllium-10 production rate relative to levels prevailing during the Holocene, suggesting a higher than normal cosmic ray exposure at that time (LaViolette, 1985(LaViolette, , 1987. Also a check of astronomical data indicated a variety of evidence supporting the idea that an energetic cosmic ray/gamma ray volley did radiate isotropically from the Galactic center and pass through the Solar System at about that time, and that this same volley is currently in the vicinity of the Crab Nebula, Tycho, and Cassiopeia A supernova remnants where it is in the process of energizing their emission (LaViolette, 1983(LaViolette, , 1987. ...
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