This image shows a portion of a 1:2,500,000 scale geologic map by PSI Senior Scientist Aileen Yingst and Research Associate Frank Chuang that encompasses the western portion of the South-Pole Aitken (SPA) Basin on the Moon. SPA is one of the oldest structures on the lunar farside (which cannot be seen directly from Earth) and is approximately 2,500 kilometers in diameter.
The SPA region has diverse volcanic materials and has excavated deep into the lower crust, providing the greatest stratigraphic cross-section on the Moon. The objectives in mapping this region are to 1) provide constraints on models of lunar volcanic generation and evolution by characterizing volcanic units along this portion of SPA Basin, 2) provide constraints on the timing and sequence of impact events by characterizing the spatial relationships and boundaries between impact-related surface materials and features found uniquely clustered in this region, and 3) characterize the extent and distribution of geologic units that are important for future lunar missions, including potential sample sites that may have high science return, as well as mineral resources derived from pyroclastic deposits of volcanic origin.
