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Arguments and Evidence Against a Younger Dryas Impact Event [chapter]

M. Boslough, K. Nicoll, V. Holliday, T. L. Daulton, D. Meltzer, N. Pinter, A. C. Scott, T. Surovell, P. Claeys, J. Gill, F. Paquay, J. Marlon (+4 others)
2013 Climates, Landscapes, and Civilizations  
In addition, the a priori odds of the impact of a >4 km comet in the prescribed configuration on the Laurentide Ice Sheet during the specified time period are infinitesimal, about one in 10 15 .  ...  We present arguments and evidence against the hypothesis that a large impact or airburst caused a significant abrupt climate change, extinction event, and termination of the Clovis culture at 12.9 ka.  ...  Sandia is a multiprogram laboratory operated  ... 
doi:10.1029/2012gm001209 fatcat:cepewhxmgzfejadier7njf4xei

Workshop on the Analysis of Interplanetary Dust Particles

Don Brownlee
1993 Meteoritics  
Backscattered electron image of a hydrated, chondritic interplanetary dust particle, measuring 17).1m across.  ...  We have no SEM equipped with a fast EDS system (the basic instrument for curatorial work on IDPs).  ...  A component of glassy silicate panicles has recently been iden tified among thechondritic lOPs [28] . The spectrum of a thin section of a glass-rich IDP [28] resembles the comet spectra. 3.  ... 
doi:10.1111/j.1945-5100.1993.tb00272.x fatcat:iejdfyqbnjfrdj5jau6lotdpqe

Natural Iron Silicides: A Systematic Review

Michael A. Rappenglück
2022 Minerals  
The other component may be a main sequence, subgiant, or red giant star [458] .  ...  The heating of the material is extremely fast, i.e., 1000 K/s. The lightning channel must be about 1mm thick.  ... 
doi:10.3390/min12020188 fatcat:u2hh3ez5g5cn5nnpythhys2cxi

Concentration of Platinum Group Elements during the Early Earth Evolution: A Review*

Arkady Pilchin, Lev Eppelbaum
2017 Natural Resources  
It is supposed that meteoritic bombardment of Earth has played a significant role in formation of PGEs deposits.  ...  Since comets are believed to be primitive bodies with a composition like that of carbonaceous chondrites [100] , it should be expected that concentrations of PGEs in comets are high.  ...  ., sulfur and chlorine), 2) mechanism which either transports these source components or removes non-ore components to allow residual concentration of metals, 3) trap (depositional mechanism for formation  ... 
doi:10.4236/nr.2017.83012 fatcat:zomjuxgsdrdbxd5tozm4irs4tq

A Review of Models and Algorithms for Surface-Underground Mining Options and Transitions Optimization: Some Lessons Learnt and the Way Forward

Bright Oppong Afum, Eugene Ben-Awuah
2021 Mining  
This requires the development of a well-integrated strategy of mining options for surface and/or underground mining and their interactions.  ...  In this study, extensive literature review and a gap analysis matrix are used to identify the limitations and opportunities for further research in surface-underground mining options and transitions optimization  ...  The Fast Lagrangian Analysis of Continua (FLAC) software based on numerical modeling and a hybrid support vector regression (v-SVR) analysis based on supervised machine learning algorithm are used to examine  ... 
doi:10.3390/mining1010008 fatcat:2q6gl5kelnd6hdnvkb2owk4pk4

Comprehensive analysis of nanodiamond evidence relating to the Younger Dryas Impact Hypothesis

Tyrone L. Daulton, Sachiko Amari, Andrew C. Scott, Mark Hardiman, Nicholas Pinter, R. Scott Anderson
2016 Journal of Quaternary Science  
for a ≈ 1,300 year interval known as the Younger Dryas stadial.  ...  We find no evidence for lonsdaleite in YDB sediments and find no evidence of a spike in nanodiamond concentration at the YDB layer to support the impact hypothesis.  ...  (d) Fast Fourier transform (FFT) of lonsdaleite ND crystal.  ... 
doi:10.1002/jqs.2892 fatcat:67hpjblsjvhvhklswsr4pvat4u

An Optimized Frame-Driven Routing Algorithm for Reconfigurable SRAM-based FPGAs

Ludovica Bozzoli, Luca Sterpone
2020 IEEE Access  
Run-time reconfiguration improves the reconfigurable computing paradigm allowing to rewrite just a portion of the FPGA configuration memory on-line.  ...  Our method is based on a frame-driven routing algorithm able to drastically reduce the number of configuration memory frames used in the design.  ...  The image has been obtained with COMET on a sample design programmed on the Kintex-7.  ... 
doi:10.1109/access.2020.2978632 fatcat:hr6wnw2lavdm7nclvswwa237d4

21. Commission de la Luminescence du Ciel

J. Dufay
1960 Transactions of the International Astronomical Union  
Determination directe au moyen des fusees La methode la plus directe et, par consequent, la plus sure pour determiner les altitudes d'emission consiste evidemment a placer des photometres a bord d'une  ...  of 6300 A interferometer (Mularchic). (4) On the spectrograms the forbidden 0+ doublet at 3726-3729 A was resolved; the intensity ratio indicates excitation by fast particles (Galperin, Korotin). (5)  ...  The apparent brightness of the zodiacal light is a very complex phenomenon depending on several components.  ... 
doi:10.1017/s0251107x00020885 fatcat:xvj5mbnxavdltpbyezunayp2wa

The Younger Dryas impact hypothesis: A requiem

Nicholas Pinter, Andrew C. Scott, Tyrone L. Daulton, Andrew Podoll, Christian Koeberl, R. Scott Anderson, Scott E. Ishman
2011 Earth-Science Reviews  
small but common component of many terrestrial deposits.  ...  l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / e a rs c i rev physics.  ...  a minute component of known lunar meteorites.  ... 
doi:10.1016/j.earscirev.2011.02.005 fatcat:2dirltpmdzdkfg5msguwjznsoe

Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP

Charles R. Kinzie, Shane S. Que Hee, Adrienne Stich, Kevin A. Tague, Chris Mercer, Joshua J. Razink, Douglas J. Kennett, Paul S. DeCarli, Ted E. Bunch, James H. Wittke, Isabel Israde-Alcántara, James L. Bischoff (+14 others)
2014 The Journal of geology  
JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive.  ...  A B S T R A C T A major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ‫ע‬ 150 years before present, forming the YD Boundary (YDB) layer, distributed  ...  A C K N O W L E D G M E N T S We thank Nick Schryvers, of the University of Antwerp, and several anonymous reviewers for detailed, helpful comments and corrections that led to significant improvements  ... 
doi:10.1086/677046 fatcat:xidc77bbpfhozmiov7gukkeu2i

Large meteorite impacts and planetary evolution

Richard Huggett
1995 Quaternary Science Reviews  
A fast saturation of mineral solution caused the formation of a great number of crystal embryos.  ...  1994 and encounters with Comet Hyakutake in 1996 and Comet Hale-Bopp in 1997.  ...  Prior to the Comet Shoemaker-Levy 9 impact with Jupiter, Zahnle and MacLow [1 ] attempted to predict the fireball luminosity history for a bolide impacting a thick H atmosphere.  ... 
doi:10.1016/0277-3791(95)90013-6 fatcat:aesdqzadlzfajdt5uxqgyssjaq

La reescritura del discurso místico y visionario en la obra de sor Francisca de Santa Teresa (1654-1709)

Carmen Alarcón Román
2014 Journal of Iberian Women Writers  
Sus ocasionales muestras de realismo y humor barrocos otorgan a su obra un rasgo de originalidad.  ...  Agradezco a su directora, Rebeca Sanmartín Bastida, la revisión y coordinación de este breve monográfico. La reescritura del discurso místico M.  ...  Así, en uno de sus coloquios, el Discurso Humano, enemigo del Alma, pretende persuadir a esta de que afronte los innumerables trabajos de la vida religiosa sin cometer excesos.  ... 
doi:10.5944/rei.vol.2.2014.12001 fatcat:vcpul3m3mfg5zpkujk64ghbkkm

Ionizing Radiation and Life

Lewis R. Dartnell
2011 Astrobiology  
This review highlights the common thread that ionizing radiation forms between the disparate component disciplines of astrobiology.  ...  Ionizing radiation is a ubiquitous feature of the Cosmos, from exogenous cosmic rays (CR) to the intrinsic mineral radioactivity of a habitable world, and its influences on the emergence and persistence  ...  The air shower is composed of a central ''hard component'' core of nuclear fragments within a spreading ''soft component'' cone of the electromagnetic cascade (Amsler et al., 2008a) .  ... 
doi:10.1089/ast.2010.0528 pmid:21774684 fatcat:6s7rpfavqnb47boq4nxdcvsy3e

Logan Medallist 4. Large-Scale Impact and Earth History

Richard A.F. Grieve
2017 Geoscience Canada  
Cela tient aux plus grandes sections transversales physiques et gravitationnelles de la Terre sur la trajectoire des astéroïdes et comètes qui pénètrent le système solaire interne.  ...  It is a preservation sample of a much larger production population, with the impact rate on Earth being higher than that of the moon.  ...  Osinski (Western U.) and A. Therriault and B. Robertson (GSC) for their stimulating intellectual interactions over the years. Thanks also go to M.  ... 
doi:10.12789/geocanj.2017.44.113 fatcat:fpdqibwkfnewrgmzwlpu3jb3ai

Chapter III: Twentieth General Assembly

J. Sahade
1988 Transactions of the International Astronomical Union  
Fortunately, technical developments are fast reducing the geographic isolation of astronomers everywhere.  ...  d'emetteurs spatiaux ou aeroportes, qui reduit l'avantage qu'il y a a placer les observatoires dans des sites isoies ; c. le niveau particulierement eieve des parasites nuisibles produits regulierement  ... 
doi:10.1017/s0251107x00016187 fatcat:fxovyyeijjaejah47e2rawqrwy
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