Beryllium - boron systematics of two distinctive CAIs from CV 3 chondrites : the relatively pristine CAI B 4 from NWA 6991 and the FUN CAI CMS - 1 from

Beryllium-boron Systematics of Refractory Inclusions in Cr2 and Cv3 Chondrites: Evidence for Be Heterogeneity

Introduction: Beryllium-10 decays to B with a half-life of 1.4 Ma, and is of interest because it is produced almost exclusively by irradiation reactions, unlike other short-lived radionuclides [1]. Previous studies have shown that the initial Solar System Be/Be ratio was in the range of ~10-10 [2-9], higher than the value expected from the galactic background (~10) [2]. While this live Be in th...

Al - Mg Systematics in a Cai from the Nwa 6991 Cv 3

SYNCHRONIZING THE ABSOLUTE AND RELATIVE CLOCKS: Pb-Pb AND Al-Mg SYSTEMATICS IN CAIs FROM THE ALLENDE AND NWA 2364 CV3 CHONDRITES

Introduction: In recent years, several high-resolution chronometers have been applied towards addressing the important question of the age of the Solar System, which is best estimated from the formation age of the calcium-aluminum-rich inclusions (CAIs), recognized as the earliest-formed solids in the solar nebula. However, there are inconsistencies in the ages of CAIs as determined by differen...

Hf–W mineral isochron for Ca,Al-rich inclusions: Age of the solar system and the timing of core formation in planetesimals

Application of Hf–W chronometry to constrain the duration of early solar system processes requires the precise knowledge of the initial Hf and W isotope compositions of the solar system. To determine these values, we investigated the Hf–W isotopic systematics of bulk samples and mineral separates from several Ca,Al-rich inclusions (CAIs) from the CV3 chondrites Allende and NWA 2364. Most of the...

U - Th - Pb AND Rb - Sr SYSTEMATICS OF ALLENDE FUN CAI CMS -

Introduction: Among the calcium-aluminum-rich inclusions (CAIs) there exists a small subgroup referred to as FUN CAIs (for Fractionation and Unidentified Nuclear effects [1]) that exhibit unusually large mass-dependent fractionations and mass-independent isotopic variations [1-3]. Understanding the origin, conditions of formation, genetic relationship of these inclusions with other CAIs and the...