Chicxulub is identified as the K–Pg impact crater
Hildebrand and colleagues published the case that a buried circular structure beneath the northern Yucatán Peninsula is an impact crater of Cretaceous–Palaeogene age, drawing together the geophysical anomaly mapped by Pemex geophysicists in the late 1970s, drill-core material, shocked quartz and the distribution of boundary deposits around the Gulf of Mexico. The gap between the 1980 hypothesis and the 1991 identification is the most instructive part of the story: for eleven years the impact hypothesis rested on a global chemical signature with no crater, and the crater when found had already been drilled by an oil company that had interpreted it as a volcanic feature.
Historical — it happened, and the record is settled.
Subjects
- Chicxulub impact crater, Yucatán · impact crater · Mexico
- The Cretaceous–Palaeogene iridium anomaly · geological and soil phenomenon · Global · not located
Evidence
Partly verified — Core facts are sourced; some optional detail is deliberately absent.
Chicxulub Crater: A possible Cretaceous/Tertiary boundary impact crater on the Yucatán Peninsula, Mexico
Supports the identification of the buried Yucatán structure as an impact crater of Cretaceous–Palaeogene age. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.
Geology · 1991 · Partly verified
Hildebrand, A. R. et al., Geology, vol. 19 (1991), pp. 867–871
Recorded on Chicxulub impact crater, Yucatán
- The Alvarez impact hypothesis is published
- Chicxulub is identified as the K–Pg impact crater
- The K–Pg boundary is dated to 66.043 ± 0.043 Ma
- IODP–ICDP Expedition 364 drills the Chicxulub peak ring
Related
Related because they share a subject in the Atlas — never because the text looks similar.