Widespread⁵⁴Cr Heterogeneity in the Inner Solar System

Dating the First Stage of Planet Formation

“…A complete digestion of fluoride complexes and Cr-rich refractory phases, such as spinel, is ensured by a subsequent dissolution in aqua regia (concentrated HCl and HNO 3 mixture in 3 : 1 ratio). The Cr purification technique is adapted from Birck & Allegre (1985), Lugmair & Shukolyukov (1998), Glavin et al (2004), Nyquist et al (2001), Ueda et al (2006), and Trinquier et al (2007), and has already been described in Yin et al (2007). Cr was separated from the major elements by elution through cationic-exchange resin in HCl medium.…”

Osmium isotope systematics of ureilites

“…For example, loss of 30% silicate melt from the precursor would passively increase the carbon content of CV-type material to 0.8 wt%, far below the observed average abundance in ureilites. Chromium isotope data for Kenna and LEW 85440 suggest that the initial Cr isotope ratios of ureilites are distinct from those of carbonaceous chondrites, but similar to the HED parent body (Shukolyukov and Lugmair, 2006;Trinquier et al, 2005). However, the origin of 54 Cr variation in the early solar system is as yet unclear and needs to be substantiated by further measurements.…”

THE ELUSIVE60Fe IN THE SOLAR NEBULA

“…Although a chemical origin has also been proposed (Fujii et al 2006), these mineral-scale anomalies are usually ascribed to incomplete mixing of the products of stellar nucleosynthesis in the early solar system (Birck 2004). Recent improvements in analytical methods and instrumentation have permitted resolution of progressively smaller isotopic anomalies for a number of elements (Ca, Cr, Ti, Ni, Mo, Ru, Ba, Sm, Nd, W) in bulk meteorites Dauphas et al 2004Dauphas et al , 2002Yin et al 2002;Hidaka et al 2003;Podosek et al 1997;Trinquier et al 2007;Chen et al 2003;Papanastassiou et al 2004;Leya et al 2008;Ranen & Jacobsen 2006;Carlson et al 2007;Bizzarro et al 2007;Andreasen & Sharma 2006;Moynier et al 2010).…”