近日，英国帝国理工学院Constantinos Charalambous团队研究了火星地幔高度异质性的地震证据。2025年8月28日，《科学》杂志发表了这一成果。
行星的内部如同一个时间胶囊，保存着其早期历史的线索。
研究组报告了在整个火星地幔中发现的千米尺度的异质性，通过深度探测火星地震释放能量的明显波前畸变来识别。这些异质性可能是行星形成时的遗留产物，意味着地幔在缓慢对流的驱动下经历了有限的混合。异质性的尺寸和残存情况约束了火星鲜为人知的地幔流变学，表明其粘度高达1021.3至1021.9帕斯卡-秒，低温依赖性低，有效活化能为70至90千焦/摩尔，表明地幔变形由位错蠕变引起。有限的混合，再加上普遍存在、尺度无关的异质性，反映了火星地幔的高度无序，这是单板行星更原始的内部演化特征，与构造活跃的地球形成鲜明对比。
附：英文原文
Title: Seismic evidence for a highly heterogeneous martian mantle
Author: Constantinos Charalambous, W. Thomas Pike, Doyeon Kim, Henri Samuel, Benjamin Fernando, Carys Bill, Philippe Lognonné, W. Bruce Banerdt
Issue&Volume: 2025-08-28
Abstract: A planet’s interior is a time capsule, preserving clues to its early history. We report the discovery of kilometer-scale heterogeneities throughout Mars’ mantle, detected seismically through pronounced wavefront distortion of energy arriving from deeply probing marsquakes. These heterogeneities, likely remnants of the planet’s formation, imply a mantle that has undergone limited mixing driven by sluggish convection. Their size and survival constrain Mars’ poorly known mantle rheology, indicating a high viscosity of 1021.3 to 1021.9 pascal-seconds and low temperature dependence, with an effective activation energy of 70 to 90 kilojoules per mole, suggesting a mantle deforming by dislocation creep. The limited mixing, coupled with ubiquitous, scale-invariant heterogeneities, reflects a highly disordered mantle, characteristic of the more primitive interior evolution of a single-plate planet, contrasting sharply with the tectonically active Earth.
DOI: adk4292
Source: https://www.science.org/doi/10.1126/science.adk4292