Comparative Mineralogy, Microstructure and Compositional Trends in the Sub-Micron Size Fractions of Mare and Highland Lunar Soils.

摘要

The morphology, mineralogy, chemical composition and optical properties of lunar soils show distinct correlations as a function of grain size and origin (1,2,3). In the 20 m size fraction, there is an increased correlation between lunar surface properties observed through remote sensing techniques and those attributed to space weathering phenomenae (1,2). Despite the establishment of recognizable trends in lunar grains 20 in size (1,2,3), the size fraction 10 m is characterized as a collective population of grains without subdivision. This investigation focuses specifically on grains in the <1 m diameter size fraction for both highland and mare derived soils. The properties of these materials provide the focus for many aspects of lunar research including the nature of space weathering on surface properties, electrostatic grain transport (4,5) and dusty plasmas (5). In this study, we have used analytical transmission and scanning transmission electron microscopy (S/TEM) to characterize the mineralogy type, microstructure and major element compositions of grains in this important size range in lunar soils.