Volcanic Surprise: Scientists Discover Signs of Recent Activity on the Moon
Recent research using samples from the Chang’e-5 mission discovered volcanic glass beads that suggest lunar volcanism persisted as recently as 123 million years ago.
This finding, supported by radioisotope dating, represents the youngest recorded volcanic activity on the Moon, challenging previous assumptions about its geological activity and offering new insights into the Moon’s thermal history.
Discovery of Youngest Lunar Volcanism
Extensive geologic evidence of ancient volcanic activity can be found on the Moon, but how long this volcanism persisted has been unclear. However, Prof. Qiuli Li’s Lab at the Institute of Geology and Geophysics of the Chinese Academy of Sciences (IGGCAS) has recently identified three volcanic glass beads from lunar soil samples collected by the Chang’e-5 mission. Their research shows that the beads were formed 123±15 million years ago (Ma), thus representing the youngest lunar volcanism confirmed by radioisotope dating so far.
The study was published on September 5 in the journal Science.
Radiometric Dating Reveals Recent Activity
Dating of lunar volcanic basalt samples returned to Earth by the Apollo and Luna missions or delivered to Earth as lunar meteorites has shown that lunar basaltic volcanism continued until at least 2.9–2.8 billion years ago (Ga). However, analysis of lunar samples returned by China’s Chang’e-5 mission has demonstrated that basaltic volcanism persisted until at least 2.0 Ga.
Remote sensing observations have indicated potentially even younger volcanism during the late Copernican era (<0.8 Ga) on the Moon. However, none of these remote observations provide a precise date for the potential volcanism. In addition, the proposed extrusions of late-Copernican mare basalt cover only restricted areas, no samples of which are available.
Glass Beads as Evidence of Volcanic Activity
Eruptions of gas-rich magma can generate magma fountains, which produce submillimeter glass beads. Such beads could potentially be deposited over wide areas and subsequently be transported further across the lunar surface by impact. The volcanic glasses could be a trace component in existing samples.
Under the guidance of Profs. Qiuli Li and Yuyang He, graduate student Biwen Wang and postdoctoral researcher Qian Zhang investigated ~3000 glass beads in lunar soil samples and identified three volcanic glass beads, based on their textures, major- and trace-element compositions, and in situ sulfur isotope analyses.
The δ34S values of the three volcanic glass beads apparently differs from impact glass beads, thus providing criteria for distinguishing volcanic glasses from impact glasses. Uranium-lead dating of the three volcanic glass beads shows that they formed 123±15 million years ago (Ma).
Implications of the Findings for Lunar Thermal History
The radioisotope dating of the three Chang’e-5 volcanic glass beads provides definitive evidence for 120-million-year-old volcanism on the Moon. The presence of such young lunar volcanism implies that small celestial bodies, such as the Moon, could maintain sufficient heat to sustain internal vitality until a very late stage. These results contribute additional constraints for geophysical models on the thermal history of the Moon’s deep interior.
For more on this research, see Tiny Glass Beads Reveal Unexpected Volcanic Activity on the Moon.
Reference: “Returned samples indicate volcanism on the Moon 120 million years ago” by Bi-Wen Wang, Qian W. L. Zhang, Yi Chen, Wenhao Zhao, Yu Liu, Guo-Qiang Tang, Hong-Xia Ma, Bin Su, Hejiu Hui, John W. Delano, Fu-Yuan Wu, Xian-Hua Li, Yuyang He and Qiu-Li Li, 5 September 2024, Science.
DOI: 10.1126/science.adk6635
This study was conducted in collaboration with Nanjing University and the State University of New York at Albany.
The samples used in this study were provided by the China National Space Administration.
This work was supported by the National Natural Science Foundation of China, the Chinese Academy of Sciences, the Institute of Geology and Geophysics of the Chinese Academy of Sciences, and the China National Postdoctoral Foundation.
