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

Micro (mu) X-ray fluorescence (XRF) analysis using synchrotron radiation (S R) has been applied for the determination of rare element (Rb, Sr, Y, Zr, N b, Ba, La, and Ce) distributions in a large collection of different lunar m are and highland rocks returned to the Earth by all successful missions of "Apollo" and "Luna". Consideration of all analytical data, obtained by mu X FA-SR method shows that most of high aluminium (HA) and very high aluminium (VHA) basalts are results of partial melting of various basaltic magmas, w hich do not originate from the magmatic ocean. Fractionation trends of rare elements in different types of lunar rocks suggest that planetary processe s (controlled by volatility of elements) took place at very early stages of the Moon planet formation. (C) 2001 Elsevier Science B.V. All rights reser ved.