The fall, recovery, classification, and initial characterization of the Hamburg, Michigan H4 chondrite
Open Access
- 27 October 2020
- journal article
- research article
- Published by Wiley in Meteoritics & Planetary Science
- Vol. 55 (11), 2341-2359
- https://doi.org/10.1111/maps.13584
Abstract
The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3He, 21Ne, and 38Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10Be concentration point to a small 40–60 cm diameter meteoroid. An 40Ar‐39Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA‐ICPMS give an average Pb‐Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb‐Pb phosphate age of 4535.3 ± 9.5 Ma and U‐Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.Keywords
Funding Information
- National Aeronautics and Space Administration (80NSSC17K0250, 80NSSC18K0854, NNX16AD34G)
- Silicon Valley Community Foundation
- Tawani Foundation
- Natural Sciences and Engineering Research Council of Canada
- Lawrence Livermore National Laboratory (17‐ERD‐001. LLNL‐JRNL‐765108, DE‐AC52‐07NA27344)
- National Science Foundation (DGE‐1144082, DGE‐1746045)
- Canada Research Chairs
This publication has 42 references indexed in Scilit:
- The Hamburg meteorite fall: Fireball trajectory, orbit, and dynamicsMeteoritics & Planetary Science, 2019
- The Renchen L5-6 chondrite breccia – The first confirmed meteorite fall from Baden-Württemberg (Germany)Geochemistry, 2019
- The accretion and impact history of the ordinary chondrite parent bodiesGeochimica et Cosmochimica Acta, 2017
- Pb–Pb dating constraints on the accretion and cooling history of chondritesGeochimica et Cosmochimica Acta, 2007
- Micromagnetic coercivity distributions and interactions in chondrules with implications for paleointensities of the early solar systemJournal of Geophysical Research, 2007
- Oxygen isotope studies of carbonaceous chondritesGeochimica et Cosmochimica Acta, 1999
- Oxygen isotope studies of achondritesGeochimica et Cosmochimica Acta, 1996
- Oxygen isotope studies of ordinary chondritesGeochimica et Cosmochimica Acta, 1991
- Plutonium, uranium and rare earths in the phosphates of ordinary chondrites—the quest for a chronometerEarth and Planetary Science Letters, 1989
- Oxygen isotopic compositions of enstatite chondrites and aubritesJournal of Geophysical Research, 1984