The mineralogy of the lunar mantle has been shaped by a sequence of several processes since the formation of the Moon, including lunar magma ocean (LMO) crystallization, cumulate overturn and partial melting during convection. We investigated the mineralogical composition of cumulates crystallized from the lunar magma ocean and their changes during mantle overturn by applying different petrological models in order to identify possibilities to further constrain the properties of the lunar mantle and the conditions of its evolution. Our results suggest that a) our combination of petrological models with constraints by overturn dynamics and seismic observations could help constrain LMO properties and b) metamorphic changes of the lunar mantle mineralogy might have significant effects on the dynamics of mantle overturn due to the associated changes in cumulate density and rheology. The degree of chemical mixing during convection, the amount of trapped liquid and fraction of plagioclase in the cumulate are important quantities that should be considered in future models simulating the evolution of lunar mantle mineralogies.
Yu, S., Tosi, N., Schwinger, S., Maurice, S., Breuer, D., Xiao, L., 2019: Overturn of Ilmenite-Bearing Cumulates in a Rheologically Weak Lunar Interior. Journal of Geophysical Research: Planets, Vol. 124, pp. 418-436. 10.1029/2018JE005739