Abstract:
:Chondrules may have played a critical role in the earliest stages of planet formation by mediating the accumulation of dust into planetesimals. However, the origin of chondrules and their significance for planetesimal accretion remain enigmatic. Here, we show that chondrules and matrix in the carbonaceous chondrite Allende have complementary (183)W anomalies resulting from the uneven distribution of presolar, stellar-derived dust. These data refute an origin of chondrules in protoplanetary collisions and, instead, indicate that chondrules and matrix formed together from a common reservoir of solar nebula dust. Because bulk Allende exhibits no (183)W anomaly, chondrules and matrix must have accreted rapidly to their parent body, implying that the majority of chondrules from a given chondrite group formed in a narrow time interval. Based on Hf-W chronometry on Allende chondrules and matrix, this event occurred ∼2 million years after formation of the first solids, about coeval to chondrule formation in ordinary chondrites.
journal_name
Proc Natl Acad Sci U S Aauthors
Budde G,Kleine T,Kruijer TS,Burkhardt C,Metzler Kdoi
10.1073/pnas.1524980113subject
Has Abstractpub_date
2016-03-15 00:00:00pages
2886-91issue
11eissn
0027-8424issn
1091-6490pii
1524980113journal_volume
113pub_type
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