High-precision Oxygen Three-isotope Sims Analyses of Ordovician Extraterrestrial Chromite Grains from Sweden and China: Debris of the L Chondrite Parent Asteroid Breakup
نویسندگان
چکیده
EXTRATERRESTRIAL CHROMITE GRAINS FROM SWEDEN AND CHINA: DEBRIS OF THE L CHONDRITE PARENT ASTEROID BREAKUP P. R. Heck, T. Ushikubo, B. Schmitz, N. T. Kita, M. J. Spicuzza and J. W. Valley, Wisc-SIMS, Department of Geology and Geophysics, University of Wisconsin, 1215 W. Dayton St., Madison, WI 53706, USA, [email protected], Department of Geology, University of Lund, Sölvegatan 12, SE-22362 Lund, Sweden.
منابع مشابه
A single asteroidal source for extraterrestrial Ordovician chromite grains from Sweden and China: High-precision oxygen three-isotope SIMS analysis
We examined oxygen three-isotope ratios of 48 extraterrestrial chromite (EC) grains extracted from mid-Ordovician sediments from two different locations in Sweden, and one location in south-central China. The ages of the sediments ( 470 Ma) coincide with the breakup event of the L chondrite parent asteroid. Elemental compositions of the chromite grains are generally consistent with their origin...
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