1/4/2024 0 Comments Olivine meteorite![]() At the boundary between the core and the overlying rocky mantle, the mineral olivine may have accumulated, producing olivine-metal mixtures called pallasites. In other cases melting was very substantial and metallic iron fell to a core. The lodranites, for example, are partial melting residues. The magma migrated away, traveling up to erupt, leaving behind a residue depleted in some minerals. This leads to planetary differentiation-the formation of a crust and underlying rocky mantle.) Some meteorites resemble the rocks left behind inside an asteroid that melted. They partially melt over a range of temperature and the initial melt is quite different in composition from the rock that is melting. (Rocks, like all complex substances, do not melt at a single melting temperature. They formed when the interior of an asteroid partially melted and the magma oozed to the surface in dikes and erupted. Some, such as eucrites, are pieces of lava flows. Several types of meteorites formed by igneous (melting) activity in asteroids. Reference: Floss, Christine, (2002) Queen Alexandra Range 93148: a new type of pyroxene pallasite? Meteoritics and Planetary Science, v. It currently appears that QUE 93148 is related in some way to main group pallasites and may be a chip of the mantle of the asteroid in which pallasites formed. Although it was originally classified as a lodranite, geochemical data soon showed that it did not belong to this group. Such was the case for QUE 93148 found in the Queen Alexandra Range, Antarctica in 1993. This is especially true when that fragment consists of only one or two different coarse-grained minerals. While this approach works fairly well for large meteorites, it is quite a bit more difficult to determine what group a meteorite belongs to when only a small fragment is found. Meteorites recovered from Antarctica and other places on Earth are generally first classified based on their mineralogies and textures. QUE 93148: A Part of the Mantle of Asteroid 4 Vesta? - A tiny meteorite tells a story of melting in the deep mantle of a big asteroid. PSRD: Meteorite QUE 93148: Asteroid Mantle Material?
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