Lunar Meteorite: Dominion Range 18262 clan
The Dominion Range 18262 clan consists of paired stones DOM 18242, 18244, 18245, 18262, 18509, 18543, 18666, & 18678
from The Meteoritical Bulletin, No. 108 Dominion Range (DOM) 18262, 18509, 18543, 18666, & 18678Dominion Range, Transantarctic Mountains, Antarctica Classification: lunar basaltic breccia Mineral Composition: Fayalite (mol%): 71-95; Ferrosilite (mol%): 29-79 Macroscopic Description – Cecilia Satterwhite (NASA-JSC). The exterior has black patches of fusion crust on a brown rusty exterior with some white specks visible. The fine grained black matrix has abundant white/tan inclusions with minor oxidation. Thin Section Description (,2) – Cari Corrigan, Tim McCoy (National Museum of Natural History, Smithsonian Institution) These sections are similar enough that one description will suffice. These sections consist of a highly brecciated assemblage of mostly single mineral grains ranging up to 0.5 mm in size. Grains are dominated by pyroxene and plagioclase with rare large olivine fragments. Polymineralic igneous fragments/clasts include coarse grained gabbro and symplectites. Melt veins and pockets were observed in all sections. DOM 18262 contains a fine grained apparently anorthositic fragment (~2 mm in max dimension) and a few melt droplets (approx. 100 microns in diameter) were observed. Olivines are fayalitic (Fa90-99), although two grains of Fa56 and Fa71 were analyzed. Pyroxene is dominantly pigeonite with fine exsolution, with orthopyroxene of Fs27Wo3 and augite Fs50Wo40. Rare high-FeO pigeonite (up to Fs80) is observed associated with the symplectite. Fe/Mn of pyroxenes ranges from ~50-70. Plagioclase is calcic with An90-97>Or0.1-0.7. These meteorites are lunar basaltic breccias, likely regolith breccias. |
| from The Meteoritical Bulletin, No. 109 Dominion Range (DOM) 18242Dominion Range, Transantarctic Mountains, Antarctica Classification: lunar basaltic breccia Mineral Composition: Ferrosilite (mol%): 31-52 Macroscopic Description – Kellye Pando. Exterior is dark grey brown with some fracturing and small (0.5-1mm) white inclusions. There are also some light grey-brown inclusions that are up to 3mm in size. Fresh interior is grey matrix with inclusions that are white, light brown or grey and up to 3mm in size. Thin Section Description (,2) – Cari Corrigan, Tim McCoy (National Museum of Natural History, Smithsonian Institution) These sections are similar enough that one description will suffice. They consist of a highly brecciated assemblage of mostly single mineral grains ranging up to 0.5 mm in size. Grains are dominated by pyroxene and plagioclase (no olivine grains were analyzed in these sections). Polymineralic igneous fragments/clasts include coarse grained gabbro and symplectites. Melt veins and pockets were observed in both sections. Pyroxene is dominantly pigeonite with fine exsolution, with orthopyroxene of Fs30Wo3 and augite Fs20-64Wo20-39. Fe/Mn of pyroxenes ranges from ~50-70. Plagioclase is calcic with An91-99Or0.1-0.3. These meteorites are lunar basaltic breccias, likely regolith breccias and are most certainly paired with DOM 18262 pairing group reported in the Fall 2019 newsletter. |
| from The Meteoritical Bulletin, No. 109 Dominion Range (DOM) 18244Dominion Range, Transantarctic Mountains, Antarctica Classification: lunar basaltic breccia Mineral Composition: Ferrosilite (mol%): 20-64 Macroscopic Description – Curtis Calva. Exterior has a dark brown fusion crust that is rough with light spots less than 1 mm. Approximately 40% fusion crust on the exterior and it is slightly fractured. Exposed interior is dark gray to black with light colored inclusions. The interior is dark gray to black with light brown and white inclusions that are less than 2 mm. Thin Section Description (,2) – Cari Corrigan, Tim McCoy (National Museum of Natural History, Smithsonian Institution) These sections are similar enough that one description will suffice. They consist of a highly brecciated assemblage of mostly single mineral grains ranging up to 0.5 mm in size. Grains are dominated by pyroxene and plagioclase (no olivine grains were analyzed in these sections). Polymineralic igneous fragments/clasts include coarse grained gabbro and symplectites. Melt veins and pockets were observed in both sections. Pyroxene is dominantly pigeonite with fine exsolution, with orthopyroxene of Fs30Wo3 and augite Fs20-64Wo20-39. Fe/Mn of pyroxenes ranges from ~50-70. Plagioclase is calcic with An91-99Or0.1-0.3. These meteorites are lunar basaltic breccias, likely regolith breccias and are most certainly paired with DOM 18262 pairing group reported in the Fall 2019 newsletter. |
| from The Meteoritical Bulletin, No. 109 Dominion Range (DOM) 18545Dominion Range, Transantarctic Mountains, Antarctica Classification: lunar basaltic breccia Mineral Composition: Ferrosilite (mol%): 32-62 Macroscopic Description – Kellye Pando. 90% of the exterior is covered with a very shiny, black fusion crust. Exposed surface is dark grey with numerous light brown and white inclusions visible. Fresh interior matrix is dark grey-black with light grey, light brown and white inclusions that measure up to 2 mm. Thin Section Description – This section consists of a highly brecciated assemblage of mostly single mineral grains ranging up to 0.5 mm in size. Grains are dominated by pyroxene and plagioclase. Polymineralic igneous fragments/clasts are gabbroic. Evidence of melting was observed as small, fine-grained perhaps quenched clasts. Pyroxenes range from Fs32-62Wo16-33. Fe/Mn of pyroxenes ranges from 53-70. Plagioclase is calcic with An87-98Or0.1-0.6. This meteorite is a lunar basaltic breccia. Pairing with the DOM 18242 group should be considered. |
| Randy Says… I have not studied the DOM 18262 clan. Zeigler et al. (2021) suggest that it may be launch paired with the MET 01210 basaltic breccia. |
More InformationMeteoritical Bulletin Database DOM 18242 | 18244 |18262 | 18509 | 18543 } 18545 | 18666 | 18678 Map References Gross J., Eckley S., Zeigler R.A., and Vander Kaaden K. E. (2020) Treasure trove Antarctica: Petrology, geochemistry and pairing of lunar meteorites Dominion Range (DOM) 18509, 18543, and 18678. 51st Lunar and Planetary Science Conference, abstract no. 2555. Hayden T. S., Barrett T. J., Zhao X., Degli-Alessandrini G., Anand M., Franchi I. A. (2021) Chlorine and hydrogen in brecciated lunar meteorites: Implications for lunar volatile history. 52nd Lunar and Planetary Science Conference, abstract no. 1550. Ireland S. M., McLeod C. L., Gawronska A. J., Brum J., and Shaulis B. J. (2021) New insights into the geological evolution of the moon via petrologic investigation of lunar basaltic meteorites Dominion Range 18262 and Dominion Range 18666. 52nd Lunar and Planetary Science Conference, abstract no. 2646. McLeod C. L., Shaulis B., Brum J. T., and Gawronska A. J., 1 (2020) More meteorites, more insights! Five new lunar basaltic meteorites from the Dominion Range. 51st Lunar and Planetary Science Conference, abstract no. 2634. Zeigler R. A., Gross J., Eckley S., and Vander Kaaden K. E. (2021) Petrology, geochemistry, and pairing of lunar meteorites from the Dominion Range. 84th Annual Meeting of the Meteoritical Society, abstract no. 6141. |