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Oxygen isotope composition of primitive achondrites (SNCs shown for comparison). Data for brachinites, winonaites, acapulcoite-lodranite clan from Greenwood et al. (2012). Data for ureilites from Clayton and Mayeda (1999). Data for Martian meteorites (SNCs) from Franchi et al. (1999) and compiled from laser fluorination analyses in the Meteoritical Bulletin. Δ17O calculated as: Δ17O = δ17O – 0.52δ18O. Individual winonaite and acapulcoite-lodranite clan samples are very highly susceptible to terrestrial weathering resulting in large shifts in δ18O and to a lesser extent Δ17O. Most analysis points for these two groups plotted on this diagram have been cleaned in EATG (ethanolamine thioglycollate) in order to reduce the influence of terrestrial weathering (see Greenwood et al., 2012 for further details). TFL: terrestrial fractionation line, Y&R: slope 1 line (Young and Russell, 1998), CCAM: carbonaceous chondrite anhydrous mineral line (Clayton et al., 1977; Clayton and Mayeda 1999). |
δ18O | δ17O | Δ17O: given | Δ17O: linear | Comment |
---|---|---|---|---|
5.0600 | 1.8500 | -0.8600 | -0.781 | Δ17O off by 0.079 |
Name | Class | δ18O | δ17O | Δ17O: calc | Δ δ18O | Δ δ17O | Δ Δ17O |
---|---|---|---|---|---|---|---|
Northwest Africa 1617 | Acapulcoite | 5.0600 | 1.8500 | -0.781 | 0 | 0 | 0 |
Ooldea 014 | Achondrite-prim-ung | 5.0450 | 1.8280 | -0.795 | -0.01 | -0.02 | -0.01 |
Northwest Africa 2627 | Acapulcoite | 4.9300 | 1.8200 | -0.744 | -0.13 | -0.03 | 0.04 |
Northwest Africa 2656 | Acapulcoite | 5.0500 | 1.7100 | -0.916 | -0.01 | -0.14 | -0.13 |
Northwest Africa 2627 | Acapulcoite | 4.9600 | 1.7500 | -0.829 | -0.1 | -0.1 | -0.05 |
Northwest Africa 2656 | Acapulcoite | 5.0400 | 1.6900 | -0.931 | -0.02 | -0.16 | -0.15 |
Northwest Africa 13917 | Winonaite | 4.9590 | 2.0550 | -0.524 | -0.1 | 0.21 | 0.26 |
Northwest Africa 12951 | Winonaite | 4.8870 | 2.0490 | -0.492 | -0.17 | 0.2 | 0.29 |
Northwest Africa 13432 | Winonaite | 4.8550 | 2.0160 | -0.509 | -0.2 | 0.17 | 0.27 |
Northwest Africa 12951 | Winonaite | 5.0350 | 2.1190 | -0.499 | -0.02 | 0.27 | 0.28 |
Northwest Africa 12543 | Winonaite | 5.1180 | 2.1200 | -0.541 | 0.06 | 0.27 | 0.24 |
Northwest Africa 10851 | Winonaite | 5.0780 | 2.1490 | -0.492 | 0.02 | 0.3 | 0.29 |
Zag (b) | Winonaite | 4.8400 | 2.0600 | -0.457 | -0.22 | 0.21 | 0.32 |
Northwest Africa 4399 | Acapulcoite | 4.8700 | 1.6100 | -0.922 | -0.19 | -0.24 | -0.14 |
Northwest Africa 2340 | CR2 | 5.3700 | 1.7700 | -1.022 | 0.31 | -0.08 | -0.24 |
Northwest Africa 6448 | Winonaite | 5.1340 | 2.1670 | -0.503 | 0.07 | 0.32 | 0.28 |
Grapevine Mesa | CBa | 5.2830 | 2.0910 | -0.656 | 0.22 | 0.24 | 0.13 |
Northwest Africa 6448 | Winonaite | 5.1550 | 2.1660 | -0.515 | 0.1 | 0.32 | 0.27 |
Northwest Africa 13917 | Winonaite | 5.1070 | 2.1790 | -0.477 | 0.05 | 0.33 | 0.3 |
Northwest Africa 13735 | Winonaite | 4.7420 | 1.9740 | -0.492 | -0.32 | 0.12 | 0.29 |
Northwest Africa 12951 | Winonaite | 4.7300 | 1.9690 | -0.491 | -0.33 | 0.12 | 0.29 |
Northwest Africa 13432 | Winonaite | 5.1960 | 2.1960 | -0.506 | 0.14 | 0.35 | 0.28 |
Northwest Africa 12543 | Winonaite | 4.6620 | 1.8800 | -0.544 | -0.4 | 0.03 | 0.24 |
Northwest Africa 10851 | Winonaite | 5.2420 | 2.2240 | -0.502 | 0.18 | 0.37 | 0.28 |
Northwest Africa 13917 | Winonaite | 5.2360 | 2.2320 | -0.491 | 0.18 | 0.38 | 0.29 |
Northwest Africa 2904 | Eucrite-pmict | 4.7400 | 2.1300 | -0.335 | -0.32 | 0.28 | 0.45 |
Northwest Africa 10085 | K4 | 5.0170 | 1.4110 | -1.198 | -0.04 | -0.44 | -0.42 |
Fortuna | Winonaite | 4.6800 | 1.6100 | -0.824 | -0.38 | -0.24 | -0.04 |
Northwest Africa 1457 | Winonaite | 5.1000 | 2.3000 | -0.352 | 0.04 | 0.45 | 0.43 |
Acfer 366 | CH3 | 4.6100 | 1.7810 | -0.616 | -0.45 | -0.07 | 0.16 |
Northwest Africa 7904 | Brachinite | 4.7810 | 2.2100 | -0.276 | -0.28 | 0.36 | 0.51 |
Northwest Africa 11729 | Eucrite-an | 4.9340 | 2.3010 | -0.265 | -0.13 | 0.45 | 0.52 |
Northwest Africa 2251 | Howardite | 5.2000 | 2.3000 | -0.404 | 0.14 | 0.45 | 0.38 |
Northwest Africa 6023 | Brachinite-an | 4.8380 | 2.2690 | -0.247 | -0.22 | 0.42 | 0.53 |
Old Homestead 003 | Howardite | 4.8800 | 2.3000 | -0.238 | -0.18 | 0.45 | 0.54 |
Erg Atouila 001 | Achondrite-ung | 4.7890 | 1.4370 | -1.053 | -0.27 | -0.41 | -0.27 |
Errachidia 004 | Winonaite | 5.2760 | 2.2960 | -0.448 | 0.22 | 0.45 | 0.33 |
Northwest Africa 13432 | Winonaite | 5.3280 | 2.2720 | -0.499 | 0.27 | 0.42 | 0.28 |