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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 |
---|---|---|---|---|
5.3280 | 2.2720 | -0.5410 | -0.499 | |
4.8550 | 2.0160 | -0.5480 | -0.509 | |
5.1960 | 2.1960 | -0.5480 | -0.506 |
Name | Class | δ18O | δ17O | Δ17O: calc | Δ δ18O | Δ δ17O | Δ Δ17O |
---|---|---|---|---|---|---|---|
Northwest Africa 6448 | Winonaite | 5.1340 | 2.1670 | -0.503 | 0.01 | 0.01 | 0 |
Northwest Africa 6448 | Winonaite | 5.1550 | 2.1660 | -0.515 | 0.03 | 0 | -0.01 |
Northwest Africa 12543 | Winonaite | 5.1180 | 2.1200 | -0.541 | -0.01 | -0.04 | -0.04 |
Northwest Africa 10851 | Winonaite | 5.0780 | 2.1490 | -0.492 | -0.05 | -0.01 | 0.01 |
Northwest Africa 12951 | Winonaite | 5.0350 | 2.1190 | -0.499 | -0.09 | -0.04 | 0.01 |
Northwest Africa 10851 | Winonaite | 5.2420 | 2.2240 | -0.502 | 0.12 | 0.06 | 0 |
Northwest Africa 1457 | Winonaite | 5.1000 | 2.3000 | -0.352 | -0.03 | 0.14 | 0.15 |
Northwest Africa 2251 | Howardite | 5.2000 | 2.3000 | -0.404 | 0.07 | 0.14 | 0.1 |
Old Homestead 003 | Howardite | 5.0200 | 2.3700 | -0.24 | -0.11 | 0.21 | 0.26 |
Northwest Africa 11729 | Eucrite-an | 4.9340 | 2.3010 | -0.265 | -0.19 | 0.14 | 0.24 |
Northwest Africa 6023 | Brachinite-an | 5.1100 | 2.4020 | -0.255 | -0.02 | 0.24 | 0.25 |
Northwest Africa 10637 | Brachinite | 5.0480 | 2.4020 | -0.223 | -0.08 | 0.24 | 0.28 |
Northwest Africa 10602 | Eucrite-melt breccia | 4.9520 | 2.3490 | -0.226 | -0.17 | 0.19 | 0.28 |
Northwest Africa 12951 | Winonaite | 4.8870 | 2.0490 | -0.492 | -0.24 | -0.11 | 0.01 |
Old Homestead 003 | Howardite | 4.8800 | 2.3000 | -0.238 | -0.25 | 0.14 | 0.27 |
El Médano 395 | Brachinite | 4.8970 | 2.3290 | -0.217 | -0.23 | 0.17 | 0.29 |
Northwest Africa 6023 | Brachinite-an | 5.1620 | 2.4450 | -0.239 | 0.04 | 0.28 | 0.27 |
Zag (b) | Winonaite | 4.8400 | 2.0600 | -0.457 | -0.29 | -0.1 | 0.05 |
Northwest Africa 6023 | Brachinite-an | 4.8380 | 2.2690 | -0.247 | -0.29 | 0.11 | 0.26 |
Northwest Africa 1617 | Acapulcoite | 5.0600 | 1.8500 | -0.781 | -0.07 | -0.31 | -0.28 |
Northwest Africa 6369 | Iron, IAB complex | 5.3900 | 2.3500 | -0.453 | 0.26 | 0.19 | 0.05 |
Ooldea 014 | Achondrite-prim-ung | 5.0450 | 1.8280 | -0.795 | -0.08 | -0.33 | -0.29 |
Northwest Africa 6023 | Brachinite-an | 5.2260 | 2.4910 | -0.227 | 0.1 | 0.33 | 0.28 |
Northwest Africa 7904 | Brachinite | 4.7810 | 2.2100 | -0.276 | -0.35 | 0.05 | 0.23 |
Jiddat al Harasis 556 | Howardite | 4.9800 | 2.4800 | -0.11 | -0.15 | 0.32 | 0.39 |
Northwest Africa 10851 | Winonaite | 5.4380 | 2.3450 | -0.483 | 0.31 | 0.18 | 0.02 |
Northwest Africa 7605 | Brachinite | 4.8220 | 2.3700 | -0.137 | -0.3 | 0.21 | 0.37 |
Northwest Africa 3151 | Brachinite | 4.8600 | 2.4200 | -0.107 | -0.27 | 0.26 | 0.4 |
Thiel Mountains 07014 | Eucrite | 5.2700 | 2.5100 | -0.23 | 0.14 | 0.35 | 0.27 |
Silistra | Achondrite-ung | 5.3000 | 2.5000 | -0.256 | 0.17 | 0.34 | 0.25 |
Northwest Africa 4042 | Achondrite-ung | 5.1780 | 2.5390 | -0.154 | 0.05 | 0.38 | 0.35 |
Northwest Africa 4929 | Brachinite | 5.3300 | 2.4900 | -0.282 | 0.2 | 0.33 | 0.22 |
Northwest Africa 2904 | Eucrite-pmict | 4.7400 | 2.1300 | -0.335 | -0.39 | -0.03 | 0.17 |
Northwest Africa 10637 | Brachinite | 5.2730 | 2.5260 | -0.216 | 0.15 | 0.36 | 0.29 |
Northwest Africa 2627 | Acapulcoite | 4.9300 | 1.8200 | -0.744 | -0.2 | -0.34 | -0.24 |
Northwest Africa 11807 | Winonaite | 5.4870 | 2.3600 | -0.493 | 0.36 | 0.2 | 0.01 |
Northwest Africa 10637 | Brachinite | 4.7940 | 2.4050 | -0.088 | -0.33 | 0.24 | 0.42 |
Al Huwaysah 010 | Achondrite-ung | 4.7300 | 2.3100 | -0.15 | -0.4 | 0.15 | 0.35 |
Northwest Africa 8059 | LL3.05 | 4.7020 | 2.2280 | -0.217 | -0.42 | 0.07 | 0.29 |
Northwest Africa 5400 | Achondrite-ung | 4.8800 | 2.5250 | -0.013 | -0.25 | 0.36 | 0.49 |
Dhofar 1983 | Lunar (feldsp. breccia) | 5.1000 | 2.6000 | -0.052 | -0.03 | 0.44 | 0.45 |
Northwest Africa 12951 | Winonaite | 4.7300 | 1.9690 | -0.491 | -0.4 | -0.19 | 0.01 |
Northwest Africa 10423 | Eucrite-cm | 4.6900 | 2.2300 | -0.209 | -0.44 | 0.07 | 0.3 |
Northwest Africa 2627 | Acapulcoite | 4.9600 | 1.7500 | -0.829 | -0.17 | -0.41 | -0.32 |
Northwest Africa 2656 | Acapulcoite | 5.0500 | 1.7100 | -0.916 | -0.08 | -0.45 | -0.41 |
Northwest Africa 8173 | Enst achon | 5.0130 | 2.6050 | -0.002 | -0.11 | 0.44 | 0.5 |
Northwest Africa 10497 | Brachinite | 4.6700 | 2.2200 | -0.208 | -0.46 | 0.06 | 0.3 |
Ooldea 014 | Achondrite-prim-ung | 5.5510 | 1.9820 | -0.905 | 0.42 | -0.18 | -0.4 |
Northwest Africa 2340 | CR2 | 5.3700 | 1.7700 | -1.022 | 0.24 | -0.39 | -0.52 |
Northwest Africa 2656 | Acapulcoite | 5.0400 | 1.6900 | -0.931 | -0.09 | -0.47 | -0.43 |
Northwest Africa 6152 | Brachinite | 4.6500 | 2.2300 | -0.188 | -0.48 | 0.07 | 0.32 |
Northwest Africa 6152 | Brachinite | 4.6500 | 2.2400 | -0.178 | -0.48 | 0.08 | 0.33 |
Northwest Africa 7904 | Brachinite | 4.9990 | 2.6340 | 0.035 | -0.13 | 0.47 | 0.54 |
Northwest Africa 12543 | Winonaite | 5.5830 | 2.3450 | -0.558 | 0.46 | 0.18 | -0.05 |
Northwest Africa 4741 | Achondrite-ung | 4.9900 | 2.6400 | 0.045 | -0.14 | 0.48 | 0.55 |
Northwest Africa 11807 | Winonaite | 5.5670 | 2.3950 | -0.5 | 0.44 | 0.23 | 0 |
Northwest Africa 4537 | Aubrite | 5.0210 | 2.6500 | 0.039 | -0.11 | 0.49 | 0.54 |