Shock Heating and Subsequent Cooling of Basaltic Shergottites: The Cases for QUE94201 and Dhofar 378Shock metamorphism is one of the most fundamental processes in the history of Martian meteorites. Especially, shergottites experienced strong shock effects (>30 GPa) most likely when they were ejected from Mars. "Maskelynitization" of plagioclase and formation of shock melts are major effects due to this severe shock. QUE94201 (QUE) and Dhofar 378 (DHO) are basaltic shergottites that are mainly composed of pyroxene and plagioclase glass. These two shergottites suffered severe shock, which generated abundant impact melt and vesiculated flow textures. In spite of similar degrees of shock between two meteorites, they are distinct in several mineralogical aspects. In this abstract, we discuss their differences to understand differences in their shock heating and subsequent cooling histories.
Mikouchi, T. (Tokyo Univ. Japan)
McKay, G. (NASA Johnson Space Center Houston, TX, United States)