U-Pb ages of chondrules and implications for the evolution of the protoplanetary disk
6 April 2017 | Seminar
A summary will be presented of our methods, results and implications of U-Pb chronometry of chondrules. We find that chondrules began forming contemporaneously with calcium-aluminum-rich inclusions and formed for ca. 3.6 Myr, a result that contradicts 26Al-26Mg results. The initial Pb isotopic compositions of individual chondrules define an initial period of primary chondrule formation in the first million years that is followed by recycling of primary chondrules for the remainder of the lifetime of the protoplanetary disk. Early chondrule formation is consistent with early and efficient planetesimal growth via chondrule accretion, as indicated/predicted by observation, theory and U-Pb dating of differentiated meteorites.
|Date||6 April 2017|
|Speaker||Prof. James Connelly, Centre for Star and Planet Formation, University of Copenhagen, Denmark|
|Area of expertise||Earth Sciences|
|Host||Institute of Geochemistry and Petrology|