{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"ea8414598530d65c2077756367d2bfcb3f35db96e106b3ea4a67bb212efdd9e8","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"c1909661066c0a82cec86e3781deb519f676819ffd31821314ed41d4d882acc0","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"earth.inner-core.anisotropy-origin","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"Seismic waves cross the inner core a few percent faster along Earth's axis than along the equator, and its eastern and western halves look different. The crystal alignment and process behind this are not known.","posed_since":"1986","precise":"Compressional waves travel about 3 percent faster on polar than equatorial paths; velocity, attenuation and anisotropy differ between quasi-eastern and quasi-western hemispheres; an innermost inner core may have a distinct anisotropy axis. Identify the iron phase (hcp or bcc) and the texturing mechanism (solidification texture, Maxwell-stress deformation, translational convection, order-disorder in Fe-Si) that reproduces all three observations. An answer is a dynamical model whose predicted texture matches global travel-time and normal-mode data.","problem_ref":null,"references":"","settled_by":"A deformation or solidification model with mineral-physics elastic constants that fits global body-wave and normal-mode anisotropy, including the hemispherical pattern.","status_note":"","title":"What produces the inner core's seismic anisotropy and hemispherical asymmetry?","topic_ref":"7cfe9fc58e1f6e93abcae219320fa93156a5400d6286e67a83bb0bb8981c5f56"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"c9202734c48ca1a727ba3b58971f0c22390675dd8f3b0db875d781e5a06a52ef","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"26f6cc9a799fdf9b650f4b98d9016c47583833e1f446737fd03ae19b4c274680","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"8Y6zXHRboBFueRziIQdI41yeVHe88_NbmxfJKPX1SD1K-i5szFUCorhd-MwLbL3E3pdG1_bkmqYrN2t3varQAQ"},"schema":"pubphys.envelope/1"},"record_hash":"c9202734c48ca1a727ba3b58971f0c22390675dd8f3b0db875d781e5a06a52ef","leaf_index":1329}