THERMAL FATIGUE: A POSSIBLE SOURCE OF STRUCTURAL MODIFICATIONS IN METEORITES

Abstract

Periodic thermal excursions, even in a low‐temperature range, may cause internal stresses and give origin to some of the observed plastic and clastic deformations in stony meteorites.An experimental test confirms our hypothesis: lattice distortions, cleavage and cracking were artificially induced in specimens of two H‐chondrites (Mills and Bur‐Gheluai) by low‐temperature “thermal fatigue.” The observed effects appear to be increasing with increasing number of cycles.