The Petrologic Type
Channel: Dominik Hezel
Date: 2019-10-21

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The petrologic type refers to possible secondary alterations on the parent body, and is numeric number between 1 and 7 (e.g., CM2, CR3, H5, EL4). Petrologic types 1 and 2 indiciate hydrothermal alteratio at lower temperatures. The most primitive, i.e., unaltered meteorites are of type 3. Petrologic type above 3 and up to 6 indicate metamorphic overprint, and type 7 shows indications of incipient melting