Petrologic characterization of CO3.0 chondrites: Implications for 60Fe-60Ni analysesOPEN ACCESS 

· by · in , , ,

Myriam Telus, Tyler D. Wickland, Kyle Kim, Steven Simon

MAPS, Version of Record online: 02 January 2025

LINK (OPEN ACCESS)
PDF (OPEN ACCESS)

“Samples in which Fe and Ni isotopes have not been disturbed by secondary processing are essential for constraining the initial solar system abundance of short-lived radionuclide 60Fe, (60Fe/56Fe)SS. However, Fe- and Ni-enriched veins and fractures within chondrules in unequilibrated ordinary chondrites (UOCs) imply late-stage open-system alteration that poses a potential problem for both bulk and in situ 60Fe-60Ni systematics. This study focuses on petrologic characterization of CO3.0s, which show significantly less secondary alteration than UOCs, potentially making them better targets for studying 60Fe-60Ni systematics. We determined the petrologic type of several CO3.0 meteorites with two independent approaches, Raman spectroscopy of matrix material and Cr2O3 content of FeO-rich olivine grains. CO3 chondrites analyzed in this study range from 3.00 to 3.2 in petrologic type with slight variations between results from the two different methods. Upon analyzing two thin sections of DOM 08006, one of the most pristine CO3 chondrites known, we found a chemically anomalous region, indicative of parent body hydrothermal alteration. Using the X-ray fluorescence microscopy beamline at the Australian Synchrotron, we collected high-resolution quantitative element maps to evaluate Fe and Ni mobilization for several CO3.0s. These results indicate that late-stage Fe and Ni mobilization like that observed in UOC samples is minor for most CO3 chondrites, highly localized and mostly limited to chondrule rims. Our results support that CO3.0s are well suited for further investigation of 60Fe-60Ni systematics and that detailed characterization of both the petrologic type and late-stage Fe and Ni mobilization of samples is important for further development of this short-lived radionuclide system.”

Related posts (automatically generated):

  1. In situ 60Fe-60Ni Systematics of Chondrules from Unequilibrated Ordinary Chondrites
  2. Mobility of Iron and Nickel at Low Temperatures: Implications for 60Fe-60Ni Systematics of Chondrules from Unequilibrated Ordinary Chondrites
  3. Fossil records of high level of 60Fe in chondrules from unequilibrated chondrites
  4. Fe-Ni and Al-Mg isotope records in UOC chondrules: Plausible stellar source of 60Fe and other short-lived nuclides in the early Solar System
  5. Low 60Fe abundance in Semarkona and Sahara 99555
  6. Abundance of 60Fe inferred from nanoSIMS study of QUE 97008 (L3.05) chondrules
  7. In Situ Constraints on the 60Fe Abundance in the Early Solar System
  8. Tracking the Distribution of 26Al and 60Fe during the Early Phases of Star and Disk Evolution
  9. Iron and Nickel Isotopes in IID and IVB Iron Meteorites: Evidence for Admixture of an SN II Component and Implications for the Initial Abundance of 60Fe
  10. Lifetime of the Outer Solar System Nebula from Carbonaceous ChondritesOPEN ACCESS 
Tags: , , , , , , , , , , , , , , , , , , , , , , , , , ,