Nanodiamond-rich layer across three continents consistent with major cosmic impact at 12,800 cal BP
Por:
Kinzie C.R., Hee S.S.Q., Stich A., Tague K.A., Mercer C., Razink J.J., Kennett D.J., DeCarli P.S., Bunch T.E., Wittke J.H., Israde-Alcántara I., Bischoff J.L., Goodyear A.C., Tankersley K.B., Kimbel D.R., Culleton B.J., Erlandson J.M., Stafford T.W., Kloosterman J.B., Moore A.M.T., Firestone R.B., Aura Tortosa J.E., Jordá Pardo J.F., West A., Kennett J.P., Wolbach W.S.
Publicada:
1 ene 2014
Categoría:
Geology
Resumen:
A major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ± 150 years before present, forming the YD Boundary (YDB) layer, distributed over 150 million km2 on four continents. In 24 dated stratigraphic sections in 10 countries of the Northern Hemisphere, the YDB layer contains a clearly defined abundance peak in nanodiamonds (NDs), a major cosmic-impact proxy. Observed ND polytypes include cubic diamonds, lonsdaleite-like crystals, and diamond-like carbon nanoparticles, called n-diamond and i-carbon. The ND abundances in bulk YDB sediments ranged up to ≈500 ppb (mean: 200 ppb) and that in carbon spherules up to ≈3700 ppb (mean: ≈750 ppb); 138 of 205 sediment samples (67%) contained no detectable NDs. Isotopic evidence indicates that YDB NDs were produced from terrestrial carbon, as with other impact diamonds, and were not derived from the impactor itself. The YDB layer is also marked by abundance peaks in other impact-related proxies, including cosmic-impact spherules, carbon spherules (some containing NDs), iridium, osmium, platinum, charcoal, aciniform carbon (soot), and high-temperature melt-glass. This contribution reviews the debate about the presence, abundance, and origin of the concentration peak in YDB NDs.We describe an updated protocol for the extraction and concentration of NDs from sediment, carbon spherules, and ice, and we describe the basis for identification and classification of YDB ND polytypes, using nine analytical approaches. The large body of evidence now obtained about YDB NDs is strongly consistent with an origin by cosmic impact at ≈12,800 cal BP and is inconsistent with formation of YDB NDs by natural terrestrial processes, including wildfires, anthropogenesis, and/or influx of cosmic dust. © 2014 by The University of Chicago. All rights reserved.
Filiaciones:
Kinzie C.R.:
Department of Chemistry, DePaul University, Chicago, IL 60614, United States
Hee S.S.Q.:
Department of Environmental Health Sciences, UCLA Center for Occupational and Environmental Health, University of California, Los Angeles, CA 90095, United States
Stich A.:
Department of Chemistry, DePaul University, Chicago, IL 60614, United States
Tague K.A.:
Department of Chemistry, DePaul University, Chicago, IL 60614, United States
Mercer C.:
National Institute for Materials Science, Tsukuba, 305-0047, Japan
Razink J.J.:
Center for Advanced Materials Characterization at Oregon, University of Oregon, Eugene, OR 97403, United States
Kennett D.J.:
Department of Anthropology, Pennsylvania State University, University Park, PA 16802, United States
DeCarli P.S.:
SRI International, Menlo Park, CA 94025, United States
Bunch T.E.:
School of Earth Science and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ 86011, United States
Wittke J.H.:
School of Earth Science and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ 86011, United States
Israde-Alcántara I.:
Departamento de GeologÃa y MineralogÃa Edificio U-4, Instituto de Ciencias de la Tierra, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán C.P. 58060, Mexico
Bischoff J.L.:
US Geological Survey, Menlo Park, CA 94025, United States
Goodyear A.C.:
South Carolina Institute of Archaeology and Anthropology, University of South Carolina, Columbia, SC 29208, United States
Tankersley K.B.:
Departments of Anthropology and Geology, University of Cincinnati, Cincinnati, OH 45221, United States
Kimbel D.R.:
Kimstar Research, Fayetteville, NC 28312, United States
Culleton B.J.:
Department of Anthropology, Pennsylvania State University, University Park, PA 16802, United States
Erlandson J.M.:
Museum of Natural and Cultural History, University of Oregon, Eugene, OR 97403, United States
Stafford T.W.:
AMS 14 C Dating Centre, Department of Physics and Astronomy, University of Aarhus, Ny Munkegade 120Aarhus, Denmark
Centre for GeoGenetics, Natural History Museum of Denmark, Geological Museum, Oester Voldgade 5-7, Copenhagen, DK-1350, Denmark
Kloosterman J.B.:
Exploration Geologist, Amsterdam, 1016NN, Netherlands
Moore A.M.T.:
College of Liberal Arts, Rochester Institute of Technology, Rochester, NY 14623, United States
Firestone R.B.:
Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
Aura Tortosa J.E.:
Departament de Prehistòria i Arqueologia, Universitat de València, Avenida Blasco Ibáñez 28, Valencia, E-46010, Spain
Jordá Pardo J.F.:
Departamento de Prehistoria y ArqueologÃa, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 7, Madrid, E-28040, Spain
West A.:
GeoScience Consulting, Dewey, AZ 86327, United States
Kennett J.P.:
Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, United States
Wolbach W.S.:
Department of Chemistry, DePaul University, Chicago, IL 60614, United States
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