近日,中国科学院地质与地球物理研究的李秋立&何雨旸及其研究团队取得一项新进展。经过不懈努力,他们发现返回的样本显示1.2亿年前月球上有火山活动
该研究团队对嫦娥五号任务采集的月球土壤样本中的约3000颗玻璃珠进行了研究,并根据其纹理、化学成分及硫同位素特征,确定了其中三颗源自火山活动。
通过铀-铅测年法,这三颗火山玻璃珠的形成时间被确定为12.3亿±1.5亿年前。研究人员还测得这些火山玻璃珠中稀土元素和钍的含量较高,这可能表明,如此近期的火山活动与地幔岩浆源中放热元素的局部富集有关。
据悉,月球上存在大量古代火山活动的地质证据,但火山作用持续的时间尚不明确。岩浆喷泉会产生火山玻璃,而此类玻璃已在月球表面样本中被发现。
附:英文原文
Title: Returned samples indicate volcanism on the Moon 120 million years ago
Author: 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, Qiu-Li Li
Issue&Volume: 2024-09-06
Abstract: There is extensive geologic evidence of ancient volcanic activity on the Moon, but it is unclear how long that volcanism persisted. Magma fountains produce volcanic glasses, which have previously been found in samples of the Moon’s surface. We investigated ~3000 glass beads in lunar soil samples collected by the Chang’e-5 mission and identified three as having a volcanic origin on the basis of their textures, chemical compositions, and sulfur isotopes. Uranium-lead dating of the three volcanic glass beads shows that they formed 123 ± 15 million years ago. We measured high abundances of rare earth elements and thorium in these volcanic glass beads, which could indicate that such recent volcanism was related to local enrichment of heat-generating elements in the mantle sources of the magma.
Source: https://www.science.org/doi/10.1126/science.adk6635