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Chicxulub impact ejecta from Albion Island, Belize |
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| Authors: | Kevin O Pope Adriana C Ocampo Alfred G Fischer Walter Alvarez Bruce W Fouke Clyde L Webster Francisco J Vega Jan Smit AEugene Fritsche Philippe Claeys |
| Institution: | a Geo Eco Arc Research, 3220 N Street NW, Suite 132, Washington, DC 20007, USA b Jet Propulsion Laboratory, California Institute of Technology, MS 183-601, 4800 Oak Grove Drive, Pasadena, CA 91109, USA c Department of Earth Sciences, University of Southern California, University Park, Los Angeles, CA 90089, USA d Department of Geology and Geophysics, University of California, Berkeley, CA 94720, USA e Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA f Geoscience Research Institute, Loma Linda University, Loma Linda, CA 92350, USA g Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico D.F., Mexico h Institute of Earth Sciences, Vrije Universiteit, de Boelelaan 1085, 1081 HV Amsterdam, Netherlands i Department of Geological Sciences, California State University, Northridge, CA 91330, USA j Museum für Naturkunde, Institut für Mineralogie, D-10115 Berlin, Germany |
| Abstract: | Impact ejecta from the Albion Formation are exposed in northern Belize. The ejecta come from the outer portion of the continuous ejecta blanket of the Chicxulub crater, which is located 360 km to the northwest. The basal unit of the Albion Formation is a  1-m-thick clay and dolomite spheroid bed composed of up to four discrete flows. The clay spheroids are altered impact glass, and the dolomite spheroids are accretionary lapilli. The upper unit is a 15-m-thick coarse diamictite bed containing altered glass, large accretionary blocks, striated, polished, and impacted cobbles, and rare shocked quartz. The abundance of accretionary clasts, evidence for atmospheric drag sorting, and the presence of multiple flows in the Albion Formation indicate that atmospheres play an important role in the formation of the outer portions of continuous ejecta blankets of large craters. |
| Keywords: | ejecta impact features Chicxulub Crater Belize |
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