Earth's compositional and mechanical layers
Crust–mantle–core and lithosphere–asthenosphere partition Earth by different properties.
Key knowledge
Crust, mantle and core primarily distinguish composition. Lithosphere and asthenosphere distinguish mechanical behavior: the lithosphere includes crust and a rigid upper-mantle portion, above a weaker, predominantly solid mantle region. A solid mantle can transmit seismic shear waves while deforming over geological time. The liquid outer core and solid inner core are distinct from this mantle layering.
Conditions and scope
- Rheology depends on temperature, pressure, composition and timescale; solid does not mean incapable of slow flow.
- Do not equate crust with lithosphere, mantle with liquid magma, or one global depth with every regional mechanical boundary.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Inspected §3.1 crust/mantle/core and lithosphere/asthenosphere paragraphs. Retains composition-versus-rheology distinction; excludes the source's lower-mantle eclogite characterization and an obligatory partial-melt cause for all weakness.
2026-10-10 · Independent Mathematics and Information editor (/root/core_math_information). Independent AI editorial review of this entry's statements, equations, applicability conditions and source coverage. Source checks apply to these claims within their stated limits.
Entry details
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- foundations-refresh.1
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