{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"82e89e697263e26688bb331b94083d3f78d198e5557361b7cef58d475b2fd63c","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"41bfb2b372da059dee6676e19ca5ad2148da751b70361f8fa3e35ee702f0e3ed","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"earth.mantle-structure.radiogenic-heat","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"Earth loses about $4.6\\mathrm{e}20\\,\\mathrm{erg}$ of heat each second through its surface, partly from decaying uranium, thorium and potassium and partly from heat left over from its formation. The split is measured with geoneutrinos (antineutrinos from radioactive decay inside Earth) and is still uncertain.","posed_since":"","precise":"Surface heat loss is about $4.6e20\\,\\mathrm{erg}/\\mathrm{s}$. Borexino (Physical Review D 2020, arXiv:1909.02257) inferred mantle radiogenic power $2.5e20\\,(+1.1e20, -1.0e20)\\,\\mathrm{erg}/\\mathrm{s}$, total radiogenic power $3.8e20\\,(+1.4e20, -1.3e20)\\,\\mathrm{erg}/\\mathrm{s}$ and a convective Urey ratio (mantle radiogenic heat over mantle heat loss) of $0.78\\,(+0.41, -0.28)$, while bulk-silicate-Earth composition models span roughly $1e20\\ \\text{to}\\ 3e20\\,\\mathrm{erg}/\\mathrm{s}$ of total radiogenic power. Determine mantle radiogenic power with uncertainty below about $3e19\\,\\mathrm{erg}/\\mathrm{s}$ and identify which composition model holds.","problem_ref":null,"references":"","settled_by":"Geoneutrino measurements at several sites including an ocean-bottom detector far from continental crust, combined with refined crustal U and Th models.","status_note":"SNO+ reported the first Western Hemisphere geoneutrino flux, 49 (+13, -12) TNU, in 2026 (arXiv:2604.05746); the mantle term remains poorly constrained.","title":"How much of Earth's heat flow comes from radioactive decay?","topic_ref":"704a212d9f3a93ea0fe758e2d498cdc938219156d755cccd033c2d677e4d8b4a"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"893a41e529174ef922d4033f325858c4e717f0031646b08e2206be8670643091","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"2d62feb944cf95474483e8692831ea595aab0e867da4f6c0e6efa625e5dace3d","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"4YQB5KolIvG2nRMghldkNIaqH-IpCSeXngxTB6dOGAVQuGZQIJf796kvOoQzTkPp-kTQom_NLFOBeK5InqsYBQ"},"schema":"pubphys.envelope/1"},"record_hash":"893a41e529174ef922d4033f325858c4e717f0031646b08e2206be8670643091","leaf_index":1340}