R5: Extraterrestrial materials

[R5-15] Heating experiments of maskelynite in Zagami and EETA 79001 Martian meteorites: Implication for their shock metamorphism

*Risa Shikina¹ (1. Tokyo Uni. Sci.)

Keywords:Shergottite, Maskelynite, Recrystallization, Residual heat

Maskelynite easily transforms to crystalline plagioclase by heating. We performed heating experiments of two shergottites (Zagami and EETA 79001) that experienced different shock pressures. The degree of maskelynite recrystallization in EETA 79001 was higher than Zagami despite higher shock degree, which is opposite to the results for experimentally shocked samples. This is probably because effect of residual heat was greater in highly shocked samples to partly cure deformed crystal structure.