LUNAR FE AND TI ABUNDANCES - COMPARISON OF LUNAR PROSPECTOR AND CLEMENTINE DATA

The Lunar Prospector neutron spectrometer data correlate well with iro n and titanium abundances obtained through analysis of Clementine spec tral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amount s of gadolinium and samarium, incompatible rare earth elements that ar e enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper Sout h Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region.