Newsletter |
37,1 |
Location |
Dominion Range |
Field Number |
21175 |
Dimensions (cm) |
5.5 x 6.0 x 4.0 |
Weight (g) |
241.80 |
Original Classification |
CO3 Chondrite |
Updated Classification |
CO3.05 Chondrite |
Pairing |
DOM 08004;
DOM 03238;
DOM 08139;
DOM 08351;
DOM 10101;
DOM 10104;
DOM 14019;
DOM 14127;
DOM 14305;
DOM 18019;
DOM 18069;
DOM 19049;
DOM 19068;
DOM 19099;
DOM 19170;
DOM 19179;
|
Fayalite (mol%): 24-56;Ferrosilite (mol%): 1-3 |
Be |
A/B |
The exteriors have black fusion crust, fractured and frothy in areas with some oxidation. Areas without fusion crust are weathered brown with some evaporites visible. The interiors are a black matrix with heavy oxidation and small white inclusions visible. |
The sections consist of abundant small (up to 1 mm) chondrules, chondrule fragments and mineral grains in a dark matrix. Metal and sulfide occur both within and rimming the chondrules. Olivine ranges in composition from Fa14-56, with a continuous range of intermediate compositions and an average at Fa31-35. Pyroxenes range Fs1-9Wo1-3. The matrix appears to consist largely of Fe-rich olivine. These meteorites are CO3 chondrites and are likely paired. |
Based on Type II (FeO-rich) chondrule olivine Cr content, this sample has been reclassified to CO3.05 chondrite. Details are reported in Righter, K. et al. (2024) Pairing relations within CO3 chondrites recovered at the Dominion Range and Miller Range, Transantarctic mountains: Constraints from chondrule olivines, noble gas, and H, C, N bulk and isotopic compositions. Meteoritics and Planetary Science 59; https://doi.org/10.1111/maps.14146. |
Comparison of DOM 03238 to many of these samples reveals that it has the same CRE age, Type II chondrule olivine Cr2O3 contents, and H, C, and N elemental and isotopic compositions. Initially thought to have a high magnetite component, its mode is only slightly higher than that measured in a number of DOM 08004 pairing group CO3s (Rubin and Li, 2019). Given all this new information, we reclassify DOM 03238 as a CO3, and add it to the DOM 08004 pairing group. Data supporting this new pairing update for DOM CO3 chondrites were presented in Righter et al. (2021, 2022, 2023) and Rubin and Li (2019). |