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2019-4-11 the Cretaceous-Paleogene Boundary With Extraterrestrial Helium-3 by Marie Minh-Thu Giron Submitted to the Department of Earth, Atmospheric and Planetary Sciences on August 26, 2013 in Partial Fulfillment of the Requirements for the Degree of Master of Science in Earth, Atmospheric and Planetary Sciences Abstract
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Helium isotope systematics uniquely identify the extraterrestrial component, which is apparently hosted within magnetite and silicate grains. In some sediments 3 He is completely derived from this source, in others the extraterrestrial fraction can be computed from the measured 3 He/ 4 He ratio.
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Cretaceous-Tertiary Boundary Event: Evidence from Extraterrestrial Helium-3 S. Mukhopadhyay,1* K. A. Farley,1 A. Montanari2 Analyses of marine carbonates through the interval 63.9 to 65.4 million years ago indicate a near-constant ßux of extraterrestrial helium-3, a
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2001-3-9 The duration of the K-T boundary is thus uncertain, with estimates ranging from a few thousand to hundreds of thousands of years . Here we use extraterrestrial
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2005-12-1 There are three obvious possibilities: 1) the 3 He is not extraterrestrial and the change in helium composition reflects variations in the abundance of terrestrial nucleogenic 3 He; 2) the 3 He is extraterrestrial and the variation in composition reflects changes in sediment accumulation rate; and 3) the change reflects real variation in IDP delivery rate.
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2000-3-28 Measurements of He in a toluene residue from the continental KT boundary clay (KTB) at Raton Basin, Colorado, revealed a clear extraterrestrial helium signal with 3 He/ 4 He ratios ≈100× the air ratio in the highest temperature steps (1.3 × 10 −7 cm 3 /g of fullerene).
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2003-1-14 The fact that a high ex traterrestrial 3 He ([ 3 He] Et)found in the Cretaceous-Tertiary boundary (KTB)clay implies a short duration of the KTB event.The high 3 He/ 4 He ratios found in the fullerenes from Meishan (China) and Sasayama (Japan)should reveal that the fullerene carriers are formed in an extraterrest rial environment.In the cosmos, the difference of helium content and isotopic composition in various sources and the high helium
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In an important study, Farley et al. (2005) measured helium concentrations and isotopic compositions in a suite of samples across the Permian–Triassic boundary at Opal Creek, Canada, to determine whether high extraterrestrial helium concentrations are associated with a
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2001-9-28 Becker et al. ( 1) presented geochemical evidence that suggests that the largest mass extinction in Earth history, at the Permian-Triassic boundary (PTB)
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2014-7-18 Extraterrestrial Soot Reveals The Demise of The Dinosaurs by Alexander Popoff Numerous scholarly articles have reported high contents of soot in the Cretaceous-Paleogene boundary layer. Asteroid theory says that, close to the impact site, wildfires were ignited by the impact fireball, whereas globally they were ignited by radiation from the reentry of hypervelocity ejecta. One []
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2019-4-11 EXTRATERRESTRIAL HELIUM-3 FLUX ACROSS THE PERMIAN/TRIASSIC BOUNDARY. ... for the first time the preservation of extra-terrestrial 3 Hein deep-sea bedded chertfrom a continuous Permian-Triassic boundary (PTB) section at Waidani in Japan, which was
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2019-2-22 Establishing geochemical constraints on mass accumulation rates across the Cretaceous-Paleogene boundary with extraterrestrial Helium-3 Research and Teaching Output of
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This is conclusive evidence for extraterrestrial helium emission. For 304 A radiation, the intensity decreases from a maximum in the daytime near the magnetic equator toward both poles, dropping sharply near 55 degrees magnetic latitude and reappearing at that latitude. Get Price; Fullerenes: An extraterrestrial carbon carrier phase for ...
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2019-2-13 RESEARCH ARTICLE Open Access Enhanced flux of extraterrestrial 3He across the Permian–Triassic boundary Tetsuji Onoue1*, Naoto Takahata2, Mitsutaka Miura1, Honami Sato3, Akira Ishikawa4, Katsuhito Soda1, Yuji Sano2 and Yukio Isozaki5 Abstract The ca 252Ma Permian–Triassic boundary (PTB) represents the most severe mass extinction event of the Phanerozoic,
Read More2000-3-28 Measurements of He in a toluene residue from the continental KT boundary clay (KTB) at Raton Basin, Colorado, revealed a clear extraterrestrial helium signal with 3 He/ 4 He ratios ≈100× the air ratio in the highest temperature steps (1.3 × 10 −7 cm 3 /g of fullerene).
Read MoreHelium isotopes, multiple Ir anomalies, spherule beds, and craters all indicate a comet shower in the late Eocene. The Cretaceous-Tertiary boundary impact event appears to have been caused by a single carbonaceous chondrite projectile, most likely of asteroid origin. Little is known of the impact record in sediments from the rest of the ...
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These high 3 He/ 4 He ratios may infer the existence of extraterrestrial helium carried in fullerenes or interplanetary dust particles. Moreover, the distribution of 3 He concentrations indicates a significant increase in the influx of extraterrestrial material before the P/T boundary, which is equivalent to the influx at the Cretaceous/Paleogene boundary, because of the long duration.
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2007-10-9 Fullerenes and ET helium. Of four sites analyzed, fullerenes with ET helium, which are associated with meteorites and ET impacts , were present in YDB sediments at three Clovis-age sites (Blackwater, Murray Springs, and Daisy Cave). In Bay M33, they also were found in glass-like carbon with an ET helium ratio that is 84 times that of air.
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2016-7-10 Tertiary boundary event: evidence from extraterrestrial helium-3. Science 291, 1952-1955 (2010). Royer, D. L. C02-forced climate thresholds during the Phanerozoic. Geochim. Cosmochim. Acta 70, 5665-5675 (2006).
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The Permian-Triassic boundary (PTB) event, which occurred about 251.4 million years ago, is marked by the most severe mass extinction in the geologic record. Recent studies of some PTB sites indicate that the extinctions occurred very abruptly, consistent with a catastrophic, possibly extraterrestrial, cause. Fullerenes (C60 to C200) from sediments at the PTB contain trapped helium and argon ...
Read More2019-4-11 EXTRATERRESTRIAL HELIUM-3 FLUX ACROSS THE PERMIAN/TRIASSIC BOUNDARY. ... for the first time the preservation of extra-terrestrial 3 Hein deep-sea bedded chertfrom a continuous Permian-Triassic boundary (PTB) section at Waidani in Japan, which was
Read More2019-2-22 Establishing geochemical constraints on mass accumulation rates across the Cretaceous-Paleogene boundary with extraterrestrial Helium-3 Research and Teaching Output of
Read MoreThis is conclusive evidence for extraterrestrial helium emission. For 304 A radiation, the intensity decreases from a maximum in the daytime near the magnetic equator toward both poles, dropping sharply near 55 degrees magnetic latitude and reappearing at that latitude. Get Price; Fullerenes: An extraterrestrial carbon carrier phase for ...
Read More
Analyses of marine carbonates through the interval 63.9 to 65.4 million years ago indicate a near-constant flux of extraterrestrial helium-3, a tracer of the accretion rate of interplanetary dust to Earth. This observation indicates that the bolide associated with the Cretaceous-Tertiary (K-T) extinction event was not accompanied by enhanced solar system dustiness and so could not have been a ...
Read MoreHelium isotopes, multiple Ir anomalies, spherule beds, and craters all indicate a comet shower in the late Eocene. The Cretaceous-Tertiary boundary impact event appears to have been caused by a single carbonaceous chondrite projectile, most likely of asteroid origin. Little is known of the impact record in sediments from the rest of the ...
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2004-2-5 dence includes fullerenes with extraterrestrial helium and argon [1, 6], Fe-Ni-Si “metamorphosed grains” of probable meteoritic origin [3], Fe-Ni metals with im-pact spherules [4,5] and shocked quartz [7,8]. The im-plication of these findings is that the P/T mass extinc-tion may have been associated with a meteorite impact.
Read Morewhich is equivalent to the influx at the Cretaceous/Paleogene boundary, because of the long duration. This increase may have caused global cooling leading to mass extinction. Key words： P/T boundary, mass extinction, extraterrestrial material, helium isotope
Read More2014-7-18 Extraterrestrial Soot Reveals The Demise of The Dinosaurs by Alexander Popoff Numerous scholarly articles have reported high contents of soot in the Cretaceous-Paleogene boundary layer. Asteroid theory says that, close to the impact site, wildfires were ignited by the impact fireball, whereas globally they were ignited by radiation from the reentry of hypervelocity ejecta. One []
Read MoreThe Permian-Triassic boundary (PTB) event, which occurred about 251.4 million years ago, is marked by the most severe mass extinction in the geologic record. Recent studies of some PTB sites indicate that the extinctions occurred very abruptly, consistent with a catastrophic, possibly extraterrestrial, cause. Fullerenes (C60 to C200) from sediments at the PTB contain trapped helium and argon ...
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