Volume 45 No. 2 – September 2022
Table 1. Newly Classified Antarctic Meteorites
| Sample Number | Weight (g) | Classification | Weathering |
Fracturing |
%Fa |
%Fs |
Magnetic Susceptibility | |
|---|---|---|---|---|---|---|---|---|
| DOM 18045 | EMPA | 48.5 | H5 CHONDRITE | B/C | A/B | 18 | 5.090 | |
| DOM 18046 | EMPA | 41.8 | H6 CHONDRITE | B/C | A/B | 19 | 5.000 | |
| DOM 18047 | EMPA | 57.0 | L6 CHONDRITE | B | B/C | 23 | 4.690 | |
| DOM 18072 | SEM | 23.9 | L5 CHONDRITE | B/C | A | 24 | 4.570 | |
| DOM 18073 | SEM | 17.3 | L6 CHONDRITE | B/C | A | 24 | 4.670 | |
| DOM 18074 | SEM | 19.9 | L5 CHONDRITE | B | A | 24 | 4.610 | |
| DOM 18075 | SEM | 18.7 | L6 CHONDRITE | B/C | A | 24 | 4.650 | |
| DOM 18076 | SEM | 17.0 | L5 CHONDRITE | B | A | 23 | 4.580 | |
| DOM 18077 | EMPA | 23.2 | H5 CHONDRITE | B | A/B | 18 | 16 | 4.910 |
| DOM 18078 | SEM | 7.9 | L5 CHONDRITE | B | A/B | 24 | 4.510 | |
| DOM 18079 | SEM | 7.9 | L5 CHONDRITE | B | A | 23 | 4.600 | |
| DOM 18080 | SEM | 18.5 | L6 CHONDRITE | B/C | A | 23 | 4.550 | |
| DOM 18081 | EMPA | 9.9 | H5 CHONDRITE | B/C | A | 18 | 16 | 5.010 |
| DOM 18082 | SEM | 14.7 | L5 CHONDRITE | B | A/B | 24 | 4.590 | |
| DOM 18083 | SEM | 22.7 | L5 CHONDRITE | B | A/B | 24 | 4.600 | |
| DOM 18084 | EMPA | 9.5 | H6 CHONDRITE | B/C | B/C | 19 | 17 | 4.840 |
| DOM 18085 | SEM | 29.4 | H6 CHONDRITE | B/C | A | 18 | 5.120 | |
| DOM 18086 | SEM | 24.4 | L6 CHONDRITE | B | A | 23 | 4.570 | |
| DOM 18087 | SEM | 16.2 | L5 CHONDRITE | B | A/B | 24 | 4.630 | |
| DOM 18088 | SEM | 13.1 | L5 CHONDRITE | B | A/B | 23 | 4.560 | |
| DOM 18089 | SEM | 19.5 | L5 CHONDRITE | B | A/B | 24 | 4.670 | |
| DOM 18100 | SEM | 16.0 | L6 CHONDRITE | B/C | B/C | 25 | 4.520 | |
| DOM 18101 | SEM | 10.0 | L5 CHONDRITE | B | A/B | 24 | 4.740 | |
| DOM 18102 | SEM | 12.3 | L5 CHONDRITE | B/C | B | 24 | 4.420 | |
| DOM 18103 | EMPA | 9.8 | L5 CHONDRITE | B/C | A/B | 25 | 21 | 4.590 |
| DOM 18104 | SEM | 9.0 | L6 CHONDRITE | B/C | A/B | 24 | 4.570 | |
| DOM 18105 | SEM | 20.8 | L6 CHONDRITE | B | A/B | 23 | 4.620 | |
| DOM 18106 | SEM | 20.0 | L5 CHONDRITE | B | A/B | 24 | 4.640 | |
| DOM 18107 | SEM | 14.6 | L5 CHONDRITE | B/C | B | 24 | 4.560 | |
| DOM 18108 | SEM | 23.9 | H6 CHONDRITE | C | A/B | 19 | 5.060 | |
| DOM 18109 | SEM | 9.3 | H6 CHONDRITE | C | A/B | 18 | 5.060 | |
| DOM 18120 | EMPA | 8.0 | H4 CHONDRITE | B/C | B | 18 | 16 | 5.070 |
| DOM 18121 | EMPA | 11.4 | L6 CHONDRITE | B/C | A/B | 25 | 21 | 4.600 |
| DOM 18122 | SEM | 4.7 | L5 CHONDRITE | B/C | B | 23 | 4.560 | |
| DOM 18123 | SEM | 7.4 | L6 CHONDRITE | B/C | B | 23 | 4.670 | |
| DOM 18124 | SEM | 7.2 | L5 CHONDRITE | B/C | B | 24 | 4.720 | |
| DOM 18125 | EMPA | 8.2 | L6 CHONDRITE | B/C | B/C | 24 | 21 | 4.500 |
| DOM 18126 | SEM | 13.5 | H6 CHONDRITE | B/C | B/C | 19 | 4.820 | |
| DOM 18127 | SEM | 11.2 | L5 CHONDRITE | B/C | B | 24 | 4.590 | |
| DOM 18128 | SEM | 3.7 | L5 CHONDRITE | B/C | A/B | 24 | 4.430 | |
| DOM 18129 | SEM | 9.0 | L6 CHONDRITE | B/C | B/C | 24 | 4.460 | |
| DOM 18140 | SEM | 47.4 | L5 CHONDRITE | A/B | A/B | 24 | 4.790 | |
| DOM 18141 | EMPA | 30.2 | L6 CHONDRITE | B | B | 25 | 21 | 4.810 |
| DOM 18142 | SEM | 45.7 | L5 CHONDRITE | A/B | A/B | 23 | 4.530 | |
| DOM 18143 | SEM | 63.4 | L6 CHONDRITE | A/B | A/B | 24 | 4.630 | |
| DOM 18144 | SEM | 37.3 | L5 CHONDRITE | A/B | A/B | 24 | 4.650 | |
| DOM 18145 | EMPA | 17.1 | H5 CHONDRITE | B | A | 18 | 16 | 5.020 |
| DOM 18146 | EMPA | 21.9 | L6 CHONDRITE | Be | B/C | 25 | 21 | 4.510 |
| DOM 18147 | SEM | 47.1 | L6 CHONDRITE | A/B | A | 24 | 4.660 | |
| DOM 18148 | SEM | 31.2 | L5 CHONDRITE | A/B | A | 24 | 4.540 | |
| DOM 18149 | SEM | 42.4 | L6 CHONDRITE | B | B | 24 | 4.530 | |
| DOM 18150 | SEM | 23.9 | L6 CHONDRITE | B | A/B | 24 | 4.590 | |
| DOM 18151 | SEM | 10.8 | L6 CHONDRITE | B | A | 24 | 4.760 | |
| DOM 18152 | SEM | 16.7 | L6 CHONDRITE | B/C | B | 24 | 4.640 | |
| DOM 18153 | SEM | 15.8 | L6 CHONDRITE | B | A/B | 24 | 4.670 | |
| DOM 18154 | SEM | 9.9 | H6 CHONDRITE | B | A/B | 19 | 4.900 | |
| DOM 18155 | SEM | 8.0 | L6 CHONDRITE | B | A/B | 23 | 4.770 | |
| DOM 18156 | SEM | 8.8 | L5 CHONDRITE | B | A/B | 24 | 4.760 | |
| DOM 18157 | SEM | 22.0 | L6 CHONDRITE | B | A | 23 | 4.540 | |
| DOM 18158 | SEM | 22.0 | L6 CHONDRITE | A/B | A | 23 | 4.600 | |
| DOM 18159 | SEM | 27.2 | L5 CHONDRITE | B | A/B | 24 | 4.630 | |
| DOM 18180 | SEM | 6.3 | H6 CHONDRITE | B | A/B | 19 | 4.700 | |
| DOM 18181 | SEM | 4.1 | L5 CHONDRITE | B | B | 24 | 4.620 | |
| DOM 18182 | SEM | 7.5 | L6 CHONDRITE | B/C | B | 24 | 4.630 | |
| DOM 18183 | EMPA | 6.8 | L6 CHONDRITE | B | B/C | 24 | 20 | 4.630 |
| DOM 18184 | SEM | 13.1 | L5 CHONDRITE | B | B | 24 | 4.650 | |
| DOM 18185 | SEM | 10.7 | H6 CHONDRITE | B/C | A/B | 19 | 4.710 | |
| DOM 18186 | SEM | 18.5 | L5 CHONDRITE | B | B | 24 | 4.680 | |
| DOM 18187 | SEM | 14.5 | L6 CHONDRITE | B | B | 24 | 4.670 | |
| DOM 18188 | SEM | 18.4 | L6 CHONDRITE | B/C | A/B | 24 | 4.680 | |
| DOM 18189 | SEM | 21.1 | L5 CHONDRITE | B | B | 23 | 4.690 | |
| DOM 18210 | SEM | 9.5 | L6 CHONDRITE | B | B | 25 | 4.600 | |
| DOM 18211 | SEM | 11.6 | L5 CHONDRITE | B | A/B | 24 | 4.560 | |
| DOM 18212 | SEM | 13.6 | L5 CHONDRITE | B | B | 24 | 4.520 | |
| DOM 18213 | SEM | 12.1 | L6 CHONDRITE | B/C | B | 23 | 4.600 | |
| DOM 18214 | SEM | 7.7 | H6 CHONDRITE | B/C | B/C | 18 | 4.870 | |
| DOM 18215 | EMPA | 9.1 | L4 CHONDRITE | A/B | B/C | 25-28 | 20-22 | 4.180 |
| DOM 18216 | SEM | 4.0 | L6 CHONDRITE | B | A/B | 23 | 4.930 | |
| DOM 18217 | EMPA | 8.6 | L6 CHONDRITE | B | B | 25 | 21 | 4.640 |
| DOM 18218 | EMPA | 12.1 | L3.8 CHONDRITE | A/B | B | 23-28 | 20-21 | 4.110 |
| DOM 18219 | SEM | 10.3 | H6 CHONDRITE | B/C | A/B | 20 | 5.080 | |
| DOM 18350 | SEM | 38.1 | L6 CHONDRITE | B/C | A | 24 | 4.580 | |
| DOM 18351 | SEM | 26.7 | L6 CHONDRITE | B/C | A | 24 | 4.460 | |
| DOM 18353 | SEM | 16.0 | L6 CHONDRITE | B/C | A | 23 | 4.530 | |
| DOM 18354 | SEM | 11.7 | L5 CHONDRITE | B/C | A | 24 | 4.690 | |
| DOM 18355 | SEM | 12.5 | L5 CHONDRITE | A/B | A | 24 | 4.450 | |
| DOM 18356 | SEM | 21.8 | L5 CHONDRITE | B/C | A | 24 | 4.550 | |
| DOM 18357 | SEM | 21.3 | H6 CHONDRITE | B/C | A | 19 | 4.830 | |
| DOM 18359 | SEM | 10.0 | H6 CHONDRITE | B/Ce | A | 19 | 5.070 | |
| DOM 18545 | EMPA | 5.5 | LUNAR-BASALTIC BRECCIA | A/B | A/B | 32-62 | 4.010 | |
| DOM 18567 | EMPA | 12.4 | H3.5 CHONDRITE | A/B | A | 5-44 | 2-20 | 4.200 |
| DOM 18568 | EMPA | 17.4 | H6 CHONDRITE | B/C | A | 19 | 17 | 5.150 |
| DOM 18620 | SEM | 22.3 | L5 CHONDRITE | B | B | 24 | 4.510 | |
| DOM 18621 | SEM | 10.8 | L5 CHONDRITE | B | B/C | 24 | 4.660 | |
| DOM 18622 | SEM | 9.2 | L6 CHONDRITE | B/C | A/B | 24 | 4.550 | |
| DOM 18623 | EMPA | 17.9 | L CHONDRITE (IMPACT MELT) | B/C | B | 24 | 4.350 | |
| DOM 18624 | SEM | 23.2 | L5 CHONDRITE | B/C | B | 24 | 4.570 | |
| DOM 18625 | SEM | 20.4 | L6 CHONDRITE | B | B/C | 24 | 4.490 | |
| DOM 18626 | SEM | 8.6 | L5 CHONDRITE | B | B | 24 | 4.550 | |
| DOM 18627 | SEM | 9.2 | L6 CHONDRITE | B | A/B | 23 | 4.520 | |
| DOM 18628 | EMPA | 6.3 | L6 CHONDRITE | B/C | B | 25 | 21 | 4.530 |
| DOM 18631 | SEM | 2.5 | L6 CHONDRITE | B/C | A/B | 24 | 4.570 | |
| DOM 18632 | SEM | 2.8 | L6 CHONDRITE | B | A/B | 23 | 4.670 | |
| DOM 18633 | SEM | 2.0 | L6 CHONDRITE | B/C | A/B | 24 | 4.410 | |
| DOM 18634 | SEM | 2.8 | L6 CHONDRITE | B/Ce | A/B | 24 | 4.620 | |
| DOM 18635 | SEM | 3.7 | L5 CHONDRITE | B | B/C | 24 | 4.630 | |
| DOM 18637 | EMPA | 8.1 | H5 CHONDRITE | B | B | 19 | 17 | 4.930 |
| DOM 18638 | SEM | 8.0 | L6 CHONDRITE | B/C | A/B | 23 | 4.650 | |
| DOM 18639 | SEM | 4.0 | H6 CHONDRITE | B/C | B | 18 | 4.830 | |
| DOM 18655 | SEM | 23.8 | L5 CHONDRITE | B/C | B | 24 | 4.520 | |
| DOM 18656 | SEM | 16.0 | L5 CHONDRITE | B/C | B | 25 | 4.420 | |
| DOM 18657 | SEM | 27.5 | L5 CHONDRITE | Be | B | 24 | 4.530 | |
| DOM 18670 | SEM | 12.6 | L5 CHONDRITE | B/C | A/B | 25 | 4.650 | |
| DOM 18671 | SEM | 13.4 | L5 CHONDRITE | Be | A/B | 23 | 4.520 | |
| DOM 18672 | SEM | 12.3 | L6 CHONDRITE | B/Ce | B/C | 24 | 4.540 | |
| DOM 18679 | SEM | 6.2 | L6 CHONDRITE | B | B | 23 | 4.610 | |
| DOM 18721 | SEM | 13.3 | L6 CHONDRITE | B/Ce | A/B | 24 | 4.620 | |
| DOM 18722 | SEM | 22.7 | H6 CHONDRITE | B/C | A/B | 18 | 5.000 | |
| DOM 18723 | SEM | 13.4 | L5 CHONDRITE | B | A/B | 24 | 4.560 | |
| DOM 18725 | SEM | 7.2 | L6 CHONDRITE | B/C | A | 24 | 4.250 | |
| DOM 18726 | SEM | 14.7 | L5 CHONDRITE | B | A/B | 24 | 4.110 | |
| DOM 18727 | SEM | 18.4 | H6 CHONDRITE | B/C | A/B | 20 | 4.570 | |
| DOM 18728 | SEM | 27.1 | L5 CHONDRITE | Be | A/B | 24 | 4.590 | |
| DOM 18729 | SEM | 21.0 | H6 CHONDRITE | B/C | A/B | 18 | 5.090 | |
| DOM 18760 | EMPA | 28.3 | H6 CHONDRITE | B/C | B/C | 19 | 17 | 4.770 |
| DOM 18761 | SEM | 10.3 | L6 CHON. (BRECCIA) | B | A/B | 24 | 4.620 | |
| DOM 18762 | SEM | 14.9 | H6 CHONDRITE | B/C | A/B | 17 | 5.030 | |
| DOM 18763 | SEM | 12.0 | L6 CHON. (BRECCIA) | B | B | 23 | 4.540 | |
| DOM 18764 | EMPA | 12.5 | H4 CHONDRITE | B | B | 18 | 16 | 5.230 |
| DOM 18765 | EMPA | 16.9 | L6 CHON. (BRECCIA) | B/Ce | B/C | 25 | 21 | 4.550 |
| DOM 18766 | SEM | 17.2 | H6 CHONDRITE | B | A/B | 18 | 4.910 | |
| DOM 18767 | SEM | 13.5 | L5 CHONDRITE | B/C | B | 24 | 4.580 | |
| DOM 18768 | SEM | 19.6 | H6 CHONDRITE | B/C | A/B | 18 | 4.960 | |
| DOM 18769 | SEM | 10.9 | H6 CHONDRITE | B/C | A/B | 17 | 5.160 | |
| DOM 18810 | SEM | 3.1 | L6 CHONDRITE | B/C | A/B | 24 | 4.330 | |
| DOM 18811 | SEM | 7.4 | H6 CHONDRITE | B/C | B | 18 | 5.040 | |
| DOM 18812 | EMPA | 4.4 | L5 CHONDRITE | B/C | A/B | 25 | 21 | 4.280 |
| DOM 18813 | SEM | 7.5 | L6 CHONDRITE | B/C | A/B | 24 | 4.360 | |
| DOM 18814 | SEM | 8.3 | H6 CHONDRITE | B/C | B/C | 18 | 4.860 | |
| DOM 18815 | SEM | 6.3 | H6 CHONDRITE | B | A/B | 17 | 4.780 | |
| DOM 18816 | EMPA | 2.0 | L5 CHONDRITE | B/C | A/B | 25 | 21 | 3.940 |
| DOM 18817 | EMPA | 1.0 | L5 CHONDRITE | B/C | A/B | 25 | 21 | 4.310 |
| DOM 18818 | SEM | 5.4 | H6 CHONDRITE | B/C | B | 18 | 5.000 | |
| DOM 18819 | SEM | 9.4 | H6 CHONDRITE | B/C | A/B | 18 | 5.000 | |
| GRO 17119 | EMPA | 22.7 | ACHON. UNGROUPED | B/C | A/B | 7 | 7 | 5.140 |
| GRO 17138 | EMPA | 7.5 | H4 CHONDRITE (ANOMALOUS) | B | A/B | 12 | 9-11 | 5.390 |
| GRO 17188 | EMPA | 45.9 | EH3 CHONDRITE | B/Ce | A | 0-2 | 5.270 | |
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) |
||||||||