{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"00da2022f75dec96671cf834c0e3e4bc78be9b6589c036154286f11a6a8fa1bc","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"ada8b4f8dd3ff501d9d35d987dd1bbb01ace6766c35dfda8bb8074a138018cba","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"earth.plate-tectonics.why-earth","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"Hot convecting planets naturally grow a stiff outer shell that does not break into plates. Something weakens Earth's shell enough to let plates form, and it is unclear what that is.","posed_since":"","precise":"Convection with strongly temperature-dependent viscosity generically produces a stagnant lid. Identify the lithospheric weakening mechanism (water, grain-size reduction and damage, pore fluids) and the planetary parameters (surface temperature, water content, mass, interior temperature) that place Earth in the mobile-lid regime and Venus outside it. An answer is a regime diagram from a rheology calibrated on experiments that places both planets correctly.","problem_ref":null,"references":"","settled_by":"Three-dimensional spherical convection with lab-calibrated weakening rheology that reproduces plate-like Earth and lid-like Venus with no tuned parameters.","status_note":"","title":"Why does Earth have plate tectonics while Venus keeps a single lid?","topic_ref":"88e7a08ea0c1d2f0e59af928067327a0eae8144a9e50f4874c49df2a02aaf5a6"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"c13ec9a8045f5cb819e9f9ac6104303ba93b9f2b900933249eac27048cc193cd","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"a0bae054a37a1c926ea94985adc5d11b0e9378e4542f2f724a472fb57f31317e","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"xKpoHprVcM59H8c1aY5D7sUhq70MZ-nGSU7zgG8sD17-hhYC3s0tbwKGa7M1ZdIEg-mjYG4bDSB6UYFuoYshAA"},"schema":"pubphys.envelope/1"},"record_hash":"c13ec9a8045f5cb819e9f9ac6104303ba93b9f2b900933249eac27048cc193cd","leaf_index":1361}