Volume 47 No. 1 – March 2024
Table 1. Newly Classified Antarctic Meteorites
| Sample Number | Weight (g) | Classification | Weathering |
Fracturing |
%Fa |
%Fs |
Magnetic Susceptibility | |
|---|---|---|---|---|---|---|---|---|
| ALH 22001 | EMPA | 726.9 | L6 Chondrite | A/Be | A/B | 25 | 21 | 4.731 |
| DOM 18013 | EMPA | 360.6 | H4 Chondrite | A/B | A | 18 | 16 | 5.280 |
| DOM 18020 | SEM | 124.2 | L6 Chondrite | A/B | A/B | 23 | 4.650 | |
| DOM 18021 | SEM | 190.7 | L6 Chondrite | B/C | B/C | 24 | 20 | 4.630 |
| DOM 18022 | SEM | 185.3 | L6 Chondrite | B | A | 24 | 22 | 4.540 |
| DOM 18023 | EMPA | 177.5 | L6 Chondrite | B/C | B/C | 24 | 21 | 4.500 |
| DOM 18024 | EMPA | 164.3 | H4 Chondrite | B/C | C | 18 | 11-17 | 4.980 |
| DOM 18027 | EMPA | 124.0 | H4 Chondrite | B | B | 18 | 15 | 5.090 |
| DOM 18034 | SEM | 161.2 | L6 Chondrite | A/B | A/B | 20 | 4.730 | |
| DOM 18035 | EMPA | 138.9 | L5 Chondrite | A/Be | A | 24 | 21 | 4.220 |
| DOM 18036 | SEM | 100.9 | L5 Chondrite | A/B | A | 23 | 20 | 4.660 |
| DOM 18037 | EMPA | 87.2 | H5 Chondrite | B | A | 19 | 17 | 5.090 |
| DOM 18038 | SEM | 66.0 | L5 Chondrite | A/B | A | 23 | 21 | 4.630 |
| DOM 18039 | SEM | 105.2 | L5 Chondrite | Be | A/B | 24 | 21 | 4.600 |
| DOM 18050 | SEM | 84.4 | L5 Chondrite | Be | A/B | 23 | 20 | 4.690 |
| DOM 18051 | SEM | 47.2 | L6 Chondrite | Be | A/B | 20 | 4.610 | |
| DOM 18054 | EMPA | 79.6 | L3.5 Chondrite | A/B | A | 1 | 1-18 | 3.810 |
| DOM 18055 | SEM | 83.9 | L6 Chondrite | B/C | A/B | 20 | 4.750 | |
| DOM 18056 | SEM | 65.6 | H6 Chondrite | B/C | A | 17 | 15 | 5.170 |
| DOM 18057 | SEM | 31.4 | L6 Chondrite | B | A | 23 | 20 | 4.520 |
| DOM 18058 | SEM | 71.6 | H6 Chondrite | B/C | A/B | 19 | 5.200 | |
| DOM 18360 | SEM | 4.8 | H6 Chondrite | B | A | 18 | 4.910 | |
| DOM 18362 | SEM | 13.2 | H5 Chondrite | B | A/B | 19 | 5.060 | |
| DOM 18363 | SEM | 9.9 | L6 Chondrite | B | A | 23 | 4.530 | |
| DOM 18364 | SEM | 17.2 | H6 Chondrite | B/C | A/B | 18 | 4.800 | |
| DOM 18365 | SEM | 4.7 | H6 Chondrite | B/C | A/B | 18 | 5.100 | |
| DOM 18366 | SEM | 12.1 | H6 Chondrite | B | A | 18 | 4.860 | |
| DOM 18367 | SEM | 13.9 | H6 Chondrite | B | A | 18 | 4.900 | |
| DOM 18368 | SEM | 8.1 | H5 Chondrite | B | A | 18 | 17 | 4.940 |
| DOM 18369 | SEM | 5.3 | H5 Chondrite | B | A/B | 17 | 5.310 | |
| DOM 18385 | EMPA | 14.5 | L6 Chondrite | B/C | B | 23 | 4.710 | |
| DOM 18388 | SEM | 23.4 | L5 Chondrite | B | A | 25 | 20 | 4.650 |
| DOM 18420 | EMPA | 8.7 | L3.6 Chondrite | B | A/B | 2 | 22 | 4.640 |
| DOM 18421 | SEM | 12.7 | L6 Chondrite | B | A | 23 | 21 | 4.600 |
| DOM 18422 | SEM | 7.5 | L6 Chondrite | B | A | 23 | 20 | 4.690 |
| DOM 18423 | SEM | 4.8 | L6 Chondrite | A/B | A | 23 | 4.670 | |
| DOM 18424 | SEM | 4.6 | H6 Chondrite | B/C | A | 19 | 17 | 4.950 |
| DOM 18425 | SEM | 2.3 | L5 Chondrite | B | A | 24 | 20 | 4.570 |
| DOM 18426 | SEM | 1.4 | H6 Chondrite | A/B | A | 19 | 17 | 5.020 |
| DOM 18427 | SEM | 1.3 | H6 Chondrite | A/B | A | 19 | 17 | 4.940 |
| DOM 18428 | SEM | 1.7 | H6 Chondrite | A/B | A | 18 | 16 | 4.950 |
| DOM 18429 | SEM | 2.8 | L6 Chondrite | B | A | 23 | 20 | 4.610 |
| DOM 18440 | SEM | 1.5 | H6 Chondrite | A/B | A | 19 | 18 | 4.900 |
| DOM 18441 | SEM | 1.1 | L3.6 Chondrite | B/C | A | 14 | 20 | 5.070 |
| DOM 18442 | EMPA | 1.4 | L6 Chondrite | B | A | 24 | 21 | 4.490 |
| DOM 18443 | SEM | 1.8 | L6 Chondrite | B | A | 24 | 21 | 4.590 |
| DOM 18445 | SEM | 1.6 | L6 Chondrite | B | A | 23 | 21 | 4.620 |
| DOM 18446 | SEM | 2.3 | L6 Chondrite | B | A | 24 | 21 | 4.730 |
| DOM 18447 | SEM | 1.0 | L3.5 Chondrite | B | A | 22 | 12-28 | 4.190 |
| DOM 18448 | EMPA | 2.6 | L6 Chondrite | B | A | 24 | 21 | 4.600 |
| DOM 18449 | SEM | 4.4 | L6 Chondrite | B | A | 24 | 20 | 4.570 |
| DOM 18506 | SEM | 9.7 | H5 Chondrite | B | A | 18 | 16 | 4.810 |
| DOM 18510 | EMPA | 20.1 | L6 Chondrite | B | A | 24 | 4.590 | |
| DOM 18511 | SEM | 23.7 | L6 Chondrite | B/C | A | 24 | 19 | 4.550 |
| DOM 18512 | SEM | 30.1 | H5 Chondrite | B | A | 17 | 16 | 4.930 |
| DOM 18513 | SEM | 16.8 | L6 Chondrite | B/C | A | 23 | 20 | 4.540 |
| DOM 18514 | SEM | 31.2 | H6 Chondrite | B/C | A | 18 | 16 | 5.100 |
| DOM 18515 | SEM | 19.4 | L6 Chondrite | A/Be | A | 23 | 20 | 4.540 |
| DOM 18516 | SEM | 16.4 | L6 Chondrite | B/C | A | 23 | 20 | 4.610 |
| DOM 18517 | SEM | 28.4 | L6 Chondrite | B/C | A/B | 23 | 21 | 4.270 |
| DOM 18518 | SEM | 23.4 | L5 Chondrite | B/C | A | 23 | 20 | 4.460 |
| DOM 18519 | SEM | 14.1 | L6 Chondrite | B/C | A | 23 | 21 | 4.390 |
| DOM 18520 | SEM | 5.2 | L6 Chondrite | B | A | 24 | 21 | 4.650 |
| DOM 18529 | EMPA | 1.9 | L6 Chondrite | A | A | 25 | 21 | 4.360 |
| DOM 18580 | EMPA | 17.2 | H6 Chondrite | A/B | A | 19 | 5.050 | |
| DOM 18581 | SEM | 14.9 | L6 Chondrite | B | A | 20 | 4.920 | |
| DOM 18582 | SEM | 19.5 | L6 Chondrite | B | A/B | 24 | 20 | 4.550 |
| DOM 18583 | SEM | 10.1 | L6 Chondrite | B | A | 24 | 20 | 4.520 |
| DOM 18584 | SEM | 7.4 | H6 Chondrite | A/B | A | 20 | 18 | 4.980 |
| DOM 18586 | SEM | 5.1 | H6 Chondrite | A/B | A | 17 | 15 | 5.090 |
| DOM 18587 | SEM | 3.3 | H4 Chondrite | A | A | 18 | 7-17 | 5.310 |
| DOM 18588 | EMPA | 4.3 | L6 Chondrite | A | A | 23 | 4.660 | |
| DOM 18589 | SEM | 1.9 | L6 Chondrite | B | A | 23 | 20 | 4.500 |
| DOM 18610 | SEM | 17.2 | L6 Chondrite | B | A | 23 | 20 | 4.600 |
| DOM 18611 | SEM | 9.4 | L6 Chondrite | B/C | A | 23 | 20 | 4.560 |
| DOM 18612 | SEM | 16.8 | L6 Chondrite | B | A | 23 | 21 | 4.620 |
| DOM 18613 | SEM | 14.0 | L6 Chondrite | B | A | 23 | 21 | 4.590 |
| DOM 18614 | SEM | 27.3 | L6 Chondrite | B/C | A | 23 | 4.620 | |
| DOM 18615 | SEM | 26.7 | L5 Chondrite | B | A | 23 | 20 | 4.700 |
| DOM 18616 | SEM | 10.7 | L5 Chondrite | B | A | 23 | 21 | 4.760 |
| DOM 18617 | SEM | 30.8 | L6 Chondrite | B/C | A | 23 | 20 | 4.540 |
| DOM 18618 | SEM | 21.0 | L6 Chondrite | B/C | A | 23 | 4.470 | |
| DOM 18619 | SEM | 16.7 | L6 Chondrite | B | A | 23 | 20 | 4.590 |
| DOM 18751 | SEM | 1.1 | H6 Chondrite | A/B | A | 20 | 4.790 | |
| DOM 18752 | SEM | 0.8 | L5 Chondrite | A/B | A | 24 | 20 | 4.610 |
| DOM 18753 | EMPA | 4.1 | H5 Chondrite | Be | A/B | 19 | 16 | 5.120 |
| DOM 18754 | EMPA | 9.3 | H6 Chondrite | B/C | A | 19 | 17 | 4.960 |
| DOM 18755 | SEM | 7.2 | H6 Chondrite | A/B | A | 20 | 4.640 | |
| DOM 18756 | SEM | 8.5 | H6 Chondrite | A/B | A | 19 | 5.000 | |
| DOM 18757 | SEM | 11.2 | L6 Chondrite | A/A | A | 24 | 21 | 4.530 |
| DOM 18758 | EMPA | 5.8 | L6 Chondrite | B | A | 24 | 4.720 | |
| DOM 18759 | SEM | 9.2 | L6 Chondrite | B | A | 24 | 21 | 4.690 |
| DOM 18770 | SEM | 5.1 | H5 Chondrite | A/B | A | 20 | 18 | 4.940 |
| DOM 18771 | SEM | 5.7 | H6 Chondrite | A/B | A | 19 | 4.780 | |
| DOM 18772 | SEM | 8.9 | L6 Chondrite | A/B | A | 25 | 21 | 4.580 |
| DOM 18773 | EMPA | 6.3 | L6 Chondrite | A/B | A | 24 | 21 | 4.530 |
| DOM 18774 | SEM | 5.1 | H6 Chondrite | A/B | A | 19 | 5.110 | |
| DOM 18775 | SEM | 9.2 | H5 Chondrite | A/B | A | 20 | 5.000 | |
| DOM 18776 | SEM | 6.8 | L6 Chondrite | Bc | A | 24 | 4.730 | |
| DOM 18777 | SEM | 3.7 | L6 Chondrite | B/C | A | 24 | 21 | 4.690 |
| DOM 18778 | EMPA | 4.7 | H6 Chondrite | B | A | 20 | 4.990 | |
| DOM 18779 | SEM | 14.1 | H6 Chondrite | A/B | A | 20 | 5.020 | |
| DOM 18782 | EMPA | 8.1 | CR2 Chondrite | B | A/B | 1 | 2-5 | 4.730 |
| DOM 18788 | EMPA | 2.7 | LL5 Chondrite | A/B | A | 30 | 25 | 3.740 |
| DOM 18789 | EMPA | 5.2 | Eucrite (Brecciated) | B/C | A | 58-64 | 2.740 | |
| DOM 18790 | SEM | 2.0 | L6 Chondrite | A/B | A | 24 | 4.700 | |
| DOM 18791 | SEM | 4.9 | H6 Chondrite | A/B | A | 19 | 17 | 4.930 |
| DOM 18792 | SEM | 3.1 | H6 Chondrite | A/B | A | 19 | 5.030 | |
| DOM 18793 | EMPA | 0.7 | L6 Chondrite | A/B | A | 25 | 21 | 4.460 |
| DOM 18794 | SEM | 1.6 | LL6 Chondrite | A/B | A | 28 | 25 | 4.020 |
| DOM 18795 | EMPA | 0.4 | L5 Chondrite | A | 24 | 20 | 4.510 | |
| DOM 18796 | EMPA | 0.8 | L6 Chondrite | A | A | 25 | 21 | 4.460 |
| DOM 18797 | SEM | 3.4 | L6 Chondrite | A/B | A | 24 | 21 | 4.380 |
| DOM 18798 | SEM | 2.0 | L6 Chondrite | A/B | A | 24 | 4.580 | |
| DOM 18799 | SEM | 7.0 | H6 Chondrite | B | A | 18 | 5.060 | |
| DOM 18803 | EMPA | 3.7 | L3.5 Chondrite | B | A | 0 | 10-16 | 4.050 |
| DOM 18808 | EMPA | 1.5 | H4 Chondrite | B/C | A/B | 18 | 16 | 5.110 |
| DOM 18850 | SEM | 9.8 | H6 Chondrite | B/C | A | 19 | 5.040 | |
| DOM 18851 | EMPA | 9.9 | H5 Chondrite | B/C | A/B | 18 | 16 | 4.180 |
| DOM 18852 | SEM | 7.4 | H6 Chondrite | B/C | A | 19 | 5.010 | |
| DOM 18853 | SEM | 8.0 | H6 Chondrite | B/C | A/B | 18 | 5.020 | |
| DOM 18854 | SEM | 8.4 | H6 Chondrite | B/C | A | 20 | 18 | 4.990 |
| DOM 18856 | SEM | 8.3 | H6 Chondrite | B/C | A | 19 | 17 | 5.080 |
| DOM 18857 | SEM | 5.5 | H6 Chondrite | B/C | A/B | 19 | 17 | 4.410 |
| DOM 18858 | SEM | 4.6 | H5 Chondrite | B/C | A | 19 | 17 | 4.320 |
| DOM 18859 | SEM | 2.5 | L6 Chondrite | B/C | A | 23 | 20 | 4.120 |
Classification of achondrites, carbonaceous chondrites and other unusual chondrites was done using electron microprobe analysis. Classification of the ordinary chondrites in Table 1 & 2 was done by Energy Dispersive Spectroscopic (EDS) methods using a Scanning Electron Microscope (SEM). This can include the analysis of several olivine and pyroxene grains to determine the approximate Fayalite and Ferrosilite values of the silicates, grouping them into H, L or LL chondrites. Petrologic types are determined by optical microscopy and are assigned based on the distinctiveness of chondrule boundaries on broken surfaces of a 1-3 g chip. While this technique is suitable for general characterization and delineation of equilibrated ordinary chondrites, those undertaking detailed study of any meteorite classified by optical methods alone should use caution. It is recommended that a polished thin section be requested to accompany any chip and appropriate steps for a more detailed characterization should be undertaken by the user. (Cari Corrigan, Smithsonian Institution) |
||||||||