The Lithologic Map of the Moon at a 1∶2,500,000-Scale

Scientific knowledge of lunar lithologies was first acquired in the 1960s–1970s. The space race between the United States (U. S.) and Soviet Union has promoted numerous manned and robotic lunar exploration missions. Utilizing datasets from these missions, the first series of lunar geologic maps was prepared and published by the U. S. Geological Survey (USGS). The definition of lunar geological features in these maps was mostly based on morphological characteristics but lacked lithological constraints owing to the incompleteness of the compositional datasets available. After two decades of silence, a new era of lunar exploration began in the 1990s when the Galileo spacecraft flew by the Moon during its gravity-assisted maneuvers. The very successful orbital missions, the Clementine and Lunar Prospector (LP), provided the first global geochemical and mineralogical (multispectral, gamma ray, neutron, etc.) datasets of the lunar surface. The 21st century is an exciting era for lunar exploration. Various missions were carried out by space agencies in Europe, Japan, India, and the U.S. China started its lunar exploration program in 2004 and has already launched two orbital missions [i.e., Chang’e-1 (CE-1) and CE-2]. These orbiting, landing, and roving missions collect diverse datasets that enable integrated research on lunar surface materials, improve our understanding of lunar magmatic evolution, and provide primary sources for this lithological mapping effort. A systematic classification scheme for endogenic lunar lithologies was reconstructed to map the compositional distribution and magmatic evolution of the lunar surface. The remote sensing datasets were compiled and integrated using Geographic Information System software to build a unified database of lunar lithologic distribution, on which subsequent lunar geologic mapping and review of lunar geologic history were based. The lessons learned from this effort are expected to be applied to other planets and small bodies in the future. The map in this repository is a pre-print version of the map which will be officially published in both Chinese and English copies by Chinese Geological Publishing House after being proofed. This pre-print map is free to use for non-commercial forms including scientific investigation and public outreach under proper citation. Please kindly cite the associated research paper (Chen et al., 2022 and references therein) published on the Science Bulletin.