Galileo imaging observations of the Palus Epidemiarum region of the Moon

New visible and near infrared multispectral images of the Moon were studied along with model ages obtained from crater counts and spectral mixing analysis to determine the volcanic histories of mare deposits in the Palus Epidemiarum region of the southern nearside. The Palus Epidemiarum, Capuanus, Lepaute E, Lacus Timoris, and Pitatus maria all have medium-high-titaniuum contents (3-7 wt.% TiO₂) whereas the Vitello R and Lacus Excellentiae mare deposits are medium-titanium basalts (<4 wt.% TiO₂). Crater counts on several of these units indicate the medium-titanium basalts are slightly older than the medium high-titanium basalts. These differences suggest either multiple, distinct sources for the basalts in the Palus Epidemiarum region, or a compositional evolution characterized by a general increase in titanium content of basalts over time. -from Authors