水星的探测与研究进展  

Exploration and research progress of planet Mercury

作　　者：李泽明 李元[1,3] LI Zeming;LI Yuan(State Key Laboratory of Isotope Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,Guangdong,China;University of Chinese Academy of Sciences,Beijing 100049,China;CAS Center for Excellence in Deep Earth Science,Guangzhou 510640,Guangdong,China)

机构地区：[1]中国科学院广州地球化学研究所同位素地球化学国家重点实验室,广东广州510640 [2]中国科学院大学,北京100049 [3]中国科学院深地科学卓越创新中心,广东广州510640

出　　处：《地球化学》2022年第2期133-160,共28页Geochimica

基　　金：中组部青年千人项目资助。

摘　　要：水星是太阳系内距离太阳最近的类地行星。水星具有类地行星中最大的未压缩密度,这意味着水星有一个巨大的金属核和异常高的金属/硅酸盐比值,研究其形成过程和机制是一个巨大的挑战。近10年来美国NASA信使号(MESSENGER)对水星的观测和数据采集极大地促进了水星的研究进展。信使号对水星表面的观测揭示了水星和地球一样具有一个全球规模的偶极磁场,这是水星具有液态的金属外核的最有力证据之一;水星表面富含挥发分但却贫铁,暗示水星可能在非常还原的条件下形成;陨石坑和火山作用在水星表面广泛分布,褶皱脊和地堑等构造单元也是盆地中常见的构造单元。这些观测对研究水星的成因、热演化历史、形成过程中元素的分配行为和表面的火山作用等提供了一定的制约。鉴于水星在太阳系类地行星中的特殊性,研究水星的地质、化学、物理特征及形成过程将有助于人们理解早期太阳系物理化学过程及类地行星的形成过程。本次研究系统地综述近年来人们根据信使号数据对水星的研究进展,并简要探讨了关于水星研究仍然可能存在的一些重要科学问题。Mercury is the innermost terrestrial planet in the solar system. It has the largest uncompressed density among the terrestrial planets, implying that Mercury has a large metallic core and a high metal/silicate ratio and poses a considerable challenge to studying the formation process and mechanism of Mercury. The data obtained from NASA’s MESSENGER mission revealed that Mercury has an Earth-like global dipolar magnetosphere, which provides strong evidence for the existence of a liquid outer core in Mercury. The surface of Mercury is volatile-rich but depleted in iron, implying that Mercury is formed under highly reduced conditions. Impact craters and volcanism are broadly spread on Mercury, and both wrinkle ridges and grabens are common tectonic units found in the basins.These observations reveal some constraints on the formation process, thermal evolution history, elements partitioning behavior, and volcanic processes of Mercury. Considering the uniqueness of Mercury among the terrestrial planets,studying its geology, geochemistry, and geophysics can provide profound insights into the physical and chemical processes of the early solar system and the formation processes of the terrestrial planets. Therefore, we systematically reviewed the most significant achievements based on NASA’s MESSENGER mission and briefly pointed out the unresolved issues.

关 键 词：水星形成机制 液态外核 富挥发分 低氧逸度 构造特征 

分 类 号：P691[天文地球—地质学]