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Edited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved July 12, 2018 (received for review May 10, 2018)
Article Figures & SI
Figures
- Fig. 1.
δ17,18O values obtained in Orgueil, Murchison, and Cold Bokkeveld IOM residues. The terrestrial fractionation line (TFL), the carbonaceous chondrite anhydrous mineral line (CCAM) (19), and the Young and Russell line (Y&R) (20) are also represented.
- Fig. 2.
NanoSIMS images showing the distribution of 12C14N, 16O, 56Fe16O, and 28Si secondary ion species in Murchison and Orgueil IOM acid maceration residues. White and cyan arrows indicate higher 56Fe16O and 28Si intensities, respectively.
- Fig. 3.
Examples of the ROIs defined on 16O ion images for one analysis each of Murchison and Orgueil acid residues. ROI#3 (Left) corresponds to intermediate O intensity, ROI#4 (Center) corresponds to O hot spots, and ROI#5 (Right) corresponds to pure IOM (see text for details).
- Fig. 4.
Calculated O isotope values for mixed compositions between the estimated IOM δ17,18O values (gray stars) in (A) Murchison and (B) Orgueil acid residues and the most negative δ17,18O values measured in mineral phases in both Murchison (approximately −40‰ for spinel; ref. 21) and Orgueil (approximately −10‰ for olivine; ref. 22) (dark gray hexagons). White dots represent 10% mixing intervals, and 20% mixing intervals are given on the diagrams from 0 to 100% mineral contribution.
- Fig. 5.
O isotope compositions measured by L-SIMS on IOM residues isolated from the Orgueil and Murchison carbonaceous chondrites. The terrestrial fractionation line (TFL), the CCAM line, and the Y&R line are also represented, together with the O isotope compositions of the Sun (17), of CI and CM chondrite components (bulk, matrix, and anhydrous silicates; refs. 21, 22, 26, and 27), of carbonaceous chondrite Ca- and Al-rich inclusions (30–32), chondrules (33–37), and carbonates (38). Estimates for the O isotope composition of CM chondrite primordial water (HW1 and HW2) are from ref. 27 for HW1 and ref. 38 for HW2.
Data supplements
Supporting Information
Insights into the origin of carbonaceous chondrite organics from their triple oxygen isotope composition
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- Physical Sciences
- Earth, Atmospheric, and Planetary Sciences
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