Seismic evidence for a highly heterogeneous martian mantle

• 成果类型: Article
• 署名作者: Charalambous, Constantinos; Pike, W. Thomas; Kim, Doyeon; Samuel, Henri; Fernando, Benjamin; Bill, Carys; Lognonne, Philippe; Banerdt, W. Bruce
• 署名单位: Imperial College London; Imperial College London; Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); Johns Hopkins University; University of Oxford; University of Oxford; California Institute of Technology; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL)
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9717
• DOI: 10.1126/science.adk4292
• 发表日期: 2025-08-28
• 页码: 899-903
• 关键词: thermal-convection; wave-fields; magma ocean; SCATTERING; mars; attenuation; insight; equilibration; viscosity; crust

摘要

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.