https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk/Head https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk http://www.nanopub.org/nschema#hasAssertion https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk/assertion https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk http://www.nanopub.org/nschema#hasProvenance https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk/provenance https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk http://www.nanopub.org/nschema#hasPublicationInfo https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk/pubinfo https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk http://www.w3.org/1999/02/22-rdf-syntax-ns#type http://www.nanopub.org/nschema#Nanopublication https://w3id.org/np/RAx3PMHxDPH81iAq2Sfo5c5C7s-CccW6n-ZFb6XYRP8Wk/assertion https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://purl.org/dc/terms/description analysis.py downloads the international periods, ages and eras tables from Macrostrat, the ICS-derived international time scale from the Paleobiology Database, and the Chalk Group record from the BGS Lexicon, and reads the top age of the Cretaceous, the Mesozoic and the Maastrichtian from each server and the youngest-age value of the Chalk Group from BGS. The largest of these seven readings (the most generous to Darwin) is taken as the time elapsed since the latter part of the Chalk, and compared with the pre-registered thresholds of 300 Ma (pass) and 150 Ma (outright refutation). https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://www.w3.org/1999/02/22-rdf-syntax-ns#type https://w3id.org/delphi/ontology/Assessment https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://www.w3.org/2000/01/rdf-schema#comment Measured: 66 Ma (age of the top of the Cretaceous / Mesozoic = end of Chalk deposition) (n = 7, all 7 readings agree to within 0 Myr; ICS quotes no error bar on the K/Pg boundary age). Interpretation: Darwin's 'latter part of the Secondary period' and 'latter part of the Chalk formation' are mapped to the top of the Cretaceous System (= top of the Mesozoic Erathem), whose numerical age is fixed by radiometric calibration in the International Chronostratigraphic Chart. The Chalk Group of south-east England is the youngest formation that was removed over the Weald, so the time since its deposition ended is an upper bound on the duration of the denudation. Darwin's own erosion-rate premise (one inch per century on a 500-foot cliff) is not tested; only his numerical conclusion is. No modern reinterpretation of the claim is needed: Darwin states a number of years, and radiometric dating measures the same quantity. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://www.w3.org/2000/01/rdf-schema#label Claim test of darwin1859-ch09-03: refutes, confidence 0.98 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://www.w3.org/2000/01/rdf-schema#seeAlso https://github.com/fractastical/delphisci/blob/bf2af6ee0a84e23ffa6414ad7a0a50a8c276506e/test-data/claim-tests/darwin-origin/darwin1859-ch09-03/result.json https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test http://www.w3.org/ns/prov#wasAttributedTo https://w3id.org/delphi/resource/agent/delphisci-claim-tester-claude-fable-5-1 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/admissibleDatasets Planned datasets: macrostrat-international-intervals, pbdb-international-timescale, bgs-lexicon-chalk-group https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/assessmentType claim-test/0.1.0 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/dataKind physical https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/disconfirmingObservation The age of the Cretaceous-Paleogene boundary is < 300 Ma. The claim is refuted outright (not merely imprecise) if it is < 150 Ma, i.e. less than half of Darwin's figure, since the denudation of the Weald cannot have taken longer than the time elapsed since the youngest Chalk was deposited. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/evidenceAgainst API responses can change when the servers adopt a newer ICS chart, so the SHA-256 values record the responses at retrieval time rather than a versioned archive file; the boundary age of 66.0 Ma has been stable across ICS chart versions since 2012. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/evidenceAgainst Darwin hedged his own number ('some crude notion'), and in the 3rd edition (1861) he withdrew the passage; the claim as stated in the 1st edition is nevertheless a definite figure and is what is tested. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/evidenceAgainst The test accepts the ICS radiometric calibration of the geological time scale as correct; the result rests on that body of dating, not on an independent measurement made here. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/evidenceAgainst Which bed counts as 'the latter part of the Secondary period' moves the target by at most a few tens of Myr (Cenomanian base 100.5 Ma to Maastrichtian top 66 Ma); no reading comes within a factor of 2.9 of 300 Ma. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/expectedObservation The age of the Cretaceous-Paleogene (Mesozoic-Cenozoic) boundary in the current International Chronostratigraphic Chart, as served by Macrostrat and cross-checked against the Paleobiology Database timescale, is >= 300 Ma; equivalently the maximum possible duration of post-Chalk denudation (time since the youngest Chalk) is >= 300 Myr. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/failCriterion The age of the Cretaceous-Paleogene boundary is < 300 Ma. The claim is refuted outright (not merely imprecise) if it is < 150 Ma, i.e. less than half of Darwin's figure, since the denudation of the Weald cannot have taken longer than the time elapsed since the youngest Chalk was deposited. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hasConfidence 0.98 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hasEvidence https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hasEvidence https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-2 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hasEvidence https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-3 https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hasVerdict refutes https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/hypothesis If Darwin is right, more than 300 million years have elapsed since the latter part of the Chalk formation (the close of the Secondary, i.e. Mesozoic, era), so the radiometric age of the top of the Cretaceous / Mesozoic must exceed 300 Ma, and the denudation of the Weald (removal of the Chalk and underlying beds over the Wealden dome) could have occupied about 300 million years. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/inferenceMethod analysis.py downloads the international periods, ages and eras tables from Macrostrat, the ICS-derived international time scale from the Paleobiology Database, and the Chalk Group record from the BGS Lexicon, and reads the top age of the Cretaceous, the Mesozoic and the Maastrichtian from each server and the youngest-age value of the Chalk Group from BGS. The largest of these seven readings (the most generous to Darwin) is taken as the time elapsed since the latter part of the Chalk, and compared with the pre-registered thresholds of 300 Ma (pass) and 150 Ma (outright refutation). https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/passCriterion The age of the Cretaceous-Paleogene (Mesozoic-Cenozoic) boundary in the current International Chronostratigraphic Chart, as served by Macrostrat and cross-checked against the Paleobiology Database timescale, is >= 300 Ma; equivalently the maximum possible duration of post-Chalk denudation (time since the youngest Chalk) is >= 300 Myr. https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/ontology/preregistered false https://w3id.org/delphi/resource/claim/darwin1859-ch09-03 https://w3id.org/delphi/ontology/hasAssessment https://w3id.org/delphi/resource/assessment/darwin1859-ch09-03--claim-test https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://purl.org/dc/terms/description top and base ages of the Cretaceous, Maastrichtian, Cenomanian and Mesozoic https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://purl.org/dc/terms/license CC BY 4.0 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/1999/02/22-rdf-syntax-ns#type https://w3id.org/delphi/ontology/EvidenceItem https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/2000/01/rdf-schema#label Dataset: Macrostrat API v2: international periods, ages and eras (ICS chart ages) https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/ns/prov#atLocation https://macrostrat.org/api/v2/defs/intervals?timescale_id=1 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/ns/prov#atLocation https://macrostrat.org/api/v2/defs/intervals?timescale_id=13 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/ns/prov#atLocation https://macrostrat.org/api/v2/defs/intervals?timescale_id=3 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 http://www.w3.org/ns/prov#wasDerivedFrom https://macrostrat.org/api/v2/defs/intervals https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 https://w3id.org/delphi/ontology/hasChecksum sha256:4900709f37f77efcf5ed5abf14b910db91204a1328bbd1625c5dce4a742d6e73 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 https://w3id.org/delphi/ontology/hasChecksum sha256:a19c091ade4263dd126341d1d8df893b5d9613cde7e03f6d00ed0a43c33ab9c8 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-1 https://w3id.org/delphi/ontology/hasChecksum sha256:d02c7f3b9c85c0d7ee487ba873a563640ec76acc12b3cf3375127fa63dd4f228 https://w3id.org/delphi/resource/evidence/darwin1859-ch09-03--claim-test--dataset-2 http://purl.org/dc/terms/description independent server for the same ICS boundary ages; 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