Publication Date:
2019-06-28
Description:
The thermal histories of ordinary chondrites and the canonical internal heating or onion shell models, which predict an inverse relation between the petrologic type of chondrites and the metallographic cooling rate, are reviewed. The thermal and accretional requirements of the 'metamorphosed planetesimal' model proposed by Scott and Rajan (1981) are analyzed, and an alternative model consistent with the metallographic cooling rate constraints is suggested in which ordinary chondrite parent bodies are collisionally fragmented and then rapidly reassembled before metamorphic heat has been dissipated.
Keywords:
LUNAR AND PLANETARY EXPLORATION
Type:
Journal of Geophysical Research (ISSN 0148-0227); 90; 2022-202
Format:
text