Alien debris in the Chang'e-5 lunar soil can provide restrictive information for understanding the plowing and migration process of lunar surface materials, the diversity of lunar crust rock composition, and the geological evolution of the lunar crust.
The research team of the Institute of Geochemistry of the Chinese Academy of Sciences obtained the composition of foreign igneous rock fragments on the young basalt geological unit of the moon 2 billion years ago by studying the lunar soil samples of Chang'e 5, and discovered the special rock fragments of the moon's crust, indicating that there are still igneous rock fragments on the moon Unrecognized geological unit.
The research work was recently published in the planetary science journal Nature Astronomy.
The Chang'e-5 landing area is a medium-titanium basalt unit formed 2 billion years ago, which is younger than the geological unit (>3 billion years) in the sampling area of the Apollo and Luna missions. The composition of matter provides new time windows.
As the lunar surface has been impacted and reformed by small celestial bodies for a long time, the lunar surface materials have been continuously broken, plowed, migrated, and mixed, so that the lunar soil in the Chang'e-5 sampling area contains a certain amount of sputtering from other areas.
The research team of the Institute of Geochemistry, Chinese Academy of Sciences analyzed more than 3,000 Chang'e-5 lunar soil particles and identified 7 igneous rock fragments different from the Chang'e-5 mesotitanium basalt, including: high-titanium glassy porphyritic rock fragments, low-titanium Basalt clastics, olivine pyroxene clastics, magnesian anorthosite clastics, highly evolved rock clastics, forsterite-rich olivine clastics and volcanic glass clastics.
The study found that the high-titanium glassy porphyritic rock clastics may be lunar olivine basalt clastics, which have different mineral composition and composition characteristics from the reported Apollo olivine basalts; found magnesian anorthosite not observed in Apollo samples Detritus, this type of rock is mainly reported in plagioclase highland breccia meteorites, which shows that the distribution of magnesia anorthosite also exists on the front of the moon; in addition, the studied volcanic glass clasts have a higher The FeO content and lower Mg# values indicate the presence of as yet unknown (more evolved) volcanic activity on the Moon.
For the first time, this research work obtained information on the composition of foreign igneous rock clastics on young basalt units on the moon 2 billion years ago, and discovered special rock clastics in the lunar crust, which provided evidence for revealing the diversity of lunar crust composition and magmatic activity.
The research indicates that there are still unrecognized geological units on the moon, which is expected to provide scientific support for planning future lunar sampling or remote sensing exploration missions.
In addition to foreign igneous rock debris, the research team has recently discovered new lunar minerals, special lunar impact sputtering, and suspected asteroid remnants in the lunar soil of Chang'e-5. Analyzing and studying these materials will help for understanding the geological evolution of the Moon.
(CCTV news client headquarter CCTV reporter Shuai Junquan)