Volatile element evolution of chondrules through time.

Chondrites and their main components, chondrules, are our guides into the evolution of the Solar System. Investigating the history of chondrules, including their volatile element history and the prevailing conditions of their formation, has implications not only for the understanding of chondrule formation and evolution but for that of larger bodies such as the terrestrial planets. Here we have determined the bulk chemical composition-rare earth, refractory, main group, and volatile element contents-of a suite of chondrules previously dated using the Pb-Pb system.

Early formation of planetary building blocks inferred from Pb isotopic ages of chondrules.

The most abundant components of primitive meteorites (chondrites) are millimeter-sized glassy spherical chondrules formed by transient melting events in the solar protoplanetary disk. Using Pb-Pb dates of 22 individual chondrules, we show that primary production of chondrules in the early solar system was restricted to the first million years after the formation of the Sun and that these existing chondrules were recycled for the remaining lifetime of the protoplanetary disk. This finding is consistent with a primary chondrule formation episode during the early high-mass accretion phase of the protoplanetary disk that transitions into a longer period of chondrule reworking.

Pb-Pb dating of individual chondrules from the CB chondrite Gujba: Assessment of the impact plume formation model.

The CB chondrites are metal-rich meteorites with characteristics that sharply distinguish them from other chondrite groups. Their unusual chemical and petrologic features and a young formation age of bulk chondrules dated from the CB chondrite Gujba are interpreted to reflect a single-stage impact origin. Here, we report high-precision internal isochrons for four individual chondrules of the Gujba chondrite to probe the formation history of CB chondrites and evaluate the concordancy of relevant short-lived radionuclide chronometers.