Large dendritic inclusions
exceeding 2 cm in diameter are uncommon in chondrites. The shift from a solid
to a dendritic structure is likely due to impact vaporization followed by
recondensation. Shock waves generated by impacts transfer a portion of their
kinetic energy into heat, resulting in impact-melt textures and, in certain
meteorites, changes to their mineral composition.
The meteorite described here is Chico, an L6
chondrite classified as an impact-melt type. Discovered in 1954 in New Mexico,
it was recovered as a single 104.8 kg stone. Within it lies a dendritic sulfide
inclusion-troilite. This troilite nodule was vaporized by the extreme heat of
the impact event and did not fully integrate into the surrounding material. As
the meteorite cooled, the vapor recondensed within the boundaries of the
original nodule, forming the dendritic texture observed today.
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