The thermal conductivity of the Earth's core and implications for its thermal and compositional evolution

• 作者: Kenji Ohta Kei Hirose
• 来源期刊: 国家科学评论（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: Special Topic:Key Problems of the Deep Earth
• 页码范围: 13-15
• 页数: 3页
• 语种: 英文
• DOI: 10.1093/nsr/nwaa303

摘要

The thermal conductivity of iron alloys is a key to understanding the mechanism of convection in the Earth's liquid core and its thermal history.The Earth's magnetic field is formed by a dynamo action that requires convection in the liquid core.Present-day outer core convection can be driven by the buoyancy of lightelement-enriched liquid that is released upon inner core solidification in addition to thermal buoyancy associated withsecular cooling.In contrast, before the birth of the inner core, the core heat loss must be more than the heat conducted down the isentropic gradient in order to drive convection by thermal buoyancy alone, which can be a tight constraint upon the core thermal evolution.