Geochemistry of rare elements in different types of lunar rocks (based on μXFA-SR data)

Micro (μ) X-ray fluorescence (XRF) analysis using synchrotron radiation (SR) has been applied for the determination of rare element (Rb, Sr, Y, Zr, Nb, Ba, La, and Ce) distributions in a large collection of different lunar mare and highland rocks returned to the Earth by all successful missions of “Apollo” and “Luna”. Consideration of all analytical data, obtained by μXFA-SR method shows that most of high aluminium (HA) and very high aluminium (VHA) basalts are results of partial melting of various basaltic magmas, which do not originate from the magmatic ocean. Fractionation trends of rare elements in different types of lunar rocks suggest that planetary processes (controlled by volatility of elements) took place at very early stages of the Moon planet formation.