Publication Date:
1998-12-04
Description:
Fayalite grains in chondrules in the oxidized, aqueously altered CV3 chondrite Mokoia have large excesses of radiogenic chromium-53. These excesses indicate the in situ decay of short-lived manganese-53 (half-life = 3.7 million years) and define an initial 53Mn/55Mn ratio of 2.32 (+/-0.18) x 10(-6). This ratio is comparable to values for carbonates in CI and CM chondrites and for several classes of differentiated meteorites. Mokoia fayalites formed 7 to 16 million years after Allende calcium-aluminum-rich inclusions, during hydrothermal activity on a geologically active asteroid after chondritic components had ceased forming in the solar nebula.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hutcheon, I D -- Krot, A N -- Keil, K -- Phinney, D L -- Scott, E R -- New York, N.Y. -- Science. 1998 Dec 4;282(5395):1865-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Lawrence Livermore National Laboratory (LLNL), Livermore, CA 94551, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9836631" target="_blank"〉PubMed〈/a〉
Keywords:
Chromium Isotopes/analysis
;
Manganese/analysis
;
*Meteoroids
;
*Minor Planets
;
Oxides/analysis
;
Radioisotopes
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
