Lunar Mingled Work in Progress ... A rock that is a mechanical mixture of different minerals and/or rock fragments (clasts). A breccia may also be distinguished by the origin of its clasts: (monomict breccia: monogenetic or monolithologic, and polymict breccia: polygenetic or polylithologic). The proportions of these fragments within the unbrecciated material Click on Term to Read More
(fragmental breccia with clasts of very low-Ti Group of silicate minerals, (Mg,Fe)2SiO4, with the compositional endpoints of forsterite (Mg2SiO4) and fayalite (Fe2SiO4). Olivine is commonly found in all chondrites within both the matrix and chondrules, achondrites including most primitive achondrites and some evolved achondrites, in pallasites as large yellow-green crystals (brown when terrestrialized), in the silicate portion Click on Term to Read More Basalt is the most common extrusive igneous rock on the terrestrial planets. For example, more than 90% of all volcanic rock on Earth is basalt. The term basalt is applied to most low viscosity dark silicate lavas, regardless of composition. Basalt is a mafic, extrusive and fine grained igneous rock Click on Term to Read More,
olivine Work in progress Coarse-grained igneous rock of basaltic composition that formed at depth and is 90% plagioclase. clinopyroxene, https://www.sandatlas.org/gabbro/ The most important mineral groups that make up this rock type are plagioclase and pyroxene. Plagioclase usually predominates over pyroxene. Plagioclase is sodium-calcium feldspar. It contains more calcium than sodium in gabbro. If there is Click on Term to Read More Igneous rock composed of crystals that have grown and accumulated (often by gravitational settling) in a cooling magma chamber. Click on Term to Read More, fragmental breccias, and Mixture of unconsolidated rocky fragments, soil, dust and other fine granular particles blanketing the surface of a body lacking an atmosphere. Regolith is the product of "gardening" by repeated meteorite impacts, and thermal processes (such as repeated heating and cooling cycles). Click on Term to Read More breccias)
click on photo for a magnified view
Purchased November 2004
no coordinates reported A stone weighing 26 g was purchased from a dealer in Morocco by N. Oakes. A portion was submitted for classification to Northern Arizona University (T. Bunch and J. Wittke). All together, four stones (11.6, 30.6, 64, and 85 g) having a combined weight of 191.2 g were classified under the NWA 2727 designation. Numerous additional stones (or parts thereof) were classified under different NWA-series designations by different labs (e.g., NWA 3160 and NWA 3333; see following photos). All of these similar stones are considered to be a pairing group, and all are also thought to belong to the previously recognized three-member pairing group composed of NWA 773, NWA 2700, and NWA 2977. Consistent with this finding, cosmogenic A nuclear species characterized by Z protons and N neutrons. Click on Term to Read More studies conducted on NWA 3160 indicate that it is likely paired with NWA 773 (Nishiizumi and Caffee, 2006). Additional paired stones have been recovered and more information and photos of this lunar pairing group can be found on the website of Randy L. Korotev–WUSL.
- Alkaline fluids (pH 7.0–12.0) were delivered by Carbonaceous chondrites represent the most primitive rock samples of our solar system. This rare (less than 5% of all meteorite falls) class of meteorites are a time capsule from the earliest days in the formation of our solar system. They are divided into the following compositional groups that, other than Click on Term to Read More meteorites to the lunar surface <2.67 b.y. ago, where the water was trapped as subsurface ice in permanently shadowed regions (PSR) within a stability depth range of 0.1 mm to >100 m.
- Impacts into existing basaltic and gabbroic lithologies in the Procellarum KREEP Terrane (PKT) and South Pole–Aitken [SPA] basin regions produced a mixed gabbroic–basaltic breccia and incorporated a component of the subsurface meteoritic water ice.
- Moganite-bearing silica micrograins precipitated from the aqueous fluid component within the gabbroic–basaltic breccia matrix at temperatures of 363–399 K and a pH of 9.5–10.5.
- The NWA 2727 lithology (sunlit) and adjacent lithologies (773 clan) were ejected from the PKT region of the Moon ~1–30 m.y. ago, during which time the shock-induced conversion of some moganite to high-pressure silica phases occurred. Based on silica solubility equations, Kayama et al. (2018) calculated that a lunar bulk water content of at least 0.6–12.3 wt % would be required to precipitate the volume of moganite present in NWA 2727.
‘Discovery of moganite in a lunar meteorite as a trace of H2O ice in the Moon’s regolith’
(https://doi.org/10.1126/sciadv.aar4378) It is generally accepted that the Moon was formed from the debris that resulted from a collision between Earth and a smaller body named ‘Theia’, which created an all-encompassing Completely molten surfaces of terrestrial planets or moons that formed soon after accretion. Samples returned by the Apollo missions provide evidence of a lunar magma ocean, crystallization of which produced a stratified Moon with a low-density crust formed by accumulation of the mineral plagioclase overlying a higher density mantle of Click on Term to Read More. It was calculated from isotopic data that the earliest time this event could have occurred is 4.517 b.y. ago (Nemchin et al., 2009), or 30–110 m.y. after the beginning of the The Sun and set of objects orbiting around it including planets and their moons and rings, asteroids, comets, and meteoroids. (Yin et al., 2002; Kleine et al., 2005). Based on Pb–Pb dating of Orthosilicate mineral, Zr(SiO4), observed in all terrestrial rocks type and in ordinary chondrites, eucrites, mesosiderites, and lunar rocks. crystals, which is a late crystallization product derived from the last dregs of the lunar magma ocean, Nemchin et al. (2009) determined that crystallization of the lunar magma ocean was complete by 4.417 (±0.006) b.y. ago, thus establishing the timeframe for the solidification of the lunar magma ocean at 100 m.y. They also reasoned that formation of an A phaneritic, intrusive igneous rock made with a modal composition (i.e. volume%) > 90% plagioclase feldspar of undefined composition (anorthitic to albitic, or combination thereof), and a small mafic component between 0 - 10% such as pyroxene, ilmenite, magnetite, and olivine 1. The name anorthosite is derived from the calcium-rich Click on Term to Read More Outermost layer of a differentiated planet, asteroid or moon, usually consisting of silicate rock and extending no more than 10s of km from the surface. The term is also applied to icy bodies, in which case it is composed of ices, frozen gases, and accumulated meteoritic material. On Earth, the Click on Term to Read More could not begin until 80–85% of the magma ocean had crystallized, which would allow relatively rapid cooling over a time interval of ~50 m.y. The final 25% of crystallization would have taken place under an insulating anorthosite crust over a similar time interval of ~50 m.y. A transmitted light view of a petrographic Thin slice or rock, usually 30 µm thick. Thin sections are used to study rocks with a petrographic microscope. of NWA 2727 can be seen on John Kashuba’s page. The photo of NWA 2727 shown above is a 2.0 g slice sectioned from the original 30.6 g stone. The specimen consists of porphyritic olivine basalt clasts of varying grain size, clasts of ferroan olivine gabbro cumulate, and a regolith breccia component, each sintered into a composite rock by shock-melt veins. The photo below shows the outside appearance of the 30.6 g parent stone.
Photo courtesy of N. Classen
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