Geological mapping of Chandrayaan-3 landing area: New insights into provenance of materials, crater chronology and origin of rocks

Abstract

This study presents the first geological map of the Chandrayaan-3 mission landing area using high resolution remote sensing datasets. The geological map reveals the spatial distribution of three distinct terrain types within the landing area that includes high-relief rugged terrain and smooth plains, and low-relief smooth plains. The Chandrayaan-3 landing site is situated within the low-relief smooth plains. The crater size-frequency distribution (CSFD) based best-fit ages of these distinct geological units are estimated to be ∼3.7 Ga (Imbrian aged). Impact crater analysis indicates that the landing area has undergone significant modification by secondary crater chains and clusters from nearby large craters. The orientation of secondary crater chains and the presence of crater ejecta rays around the landing site suggest that Schomberger crater materials possibly mantled the landing area. This interpretation is supported by the comparable ages of the mapped geological units within the landing area and the Schomberger crater floor (∼3.7 Ga). Analysis of rock distribution within the landing area indicates that a 540 m diameter fresh crater located 14 km south of the landing site is a major source of meter-sized rocks, with 81.5 % of rocks ≥5 m in size originating from this fresh crater. Moreover, the local area navigated by the rover hosts centimeter-sized rock fragments, particularly toward the west of the landing site, which is linked to excavation by a 10 m diameter crater (western crater). These results provide valuable context for the interpretation of Chandrayaan-3 mission data and contribute to understanding of the geological history of the Moon's southern high-latitude region.