Geostratigraphic mapping of the intrusive Valentine Domes on the Moon

Lunar intrusive igneous rocks have not been widely studied in the past; this is related to their rare occurrence in the surface of the Moon, and the difficulty to identify them. Most of the known structures of this type were discovered with telescopic images and were identified as intrusive domes, which are characterized by their oval shape, low slope, and subtle effect in the topography. We analyzed one of these systems with modern datasets and techniques, the Valentine domes, located near the rim of the west Serenitatis basin. We created a geostratigraphic map of the zone, combining geomorphological and spectral classifications. The aspect map turned out to be the most suitable product to search and delimit these structures, it also allowed the identification of a new dome southeast of the principal body, meaning the intrusive system is bigger than previously thought. From the detailed mapping, it was found that the three domes can be classified as laccoliths; and that several secondary structures such as rilles, dykes, and secondary domes record different stages of intrusive activity in the location. A crater counting analysis revealed that the system was active at least until 1.88 Ga ago. Finally, similar intrusive bodies on Earth host ore minerals, which highlights their importance as a target for future exploration.