| Titre | Chicxulub Crater: a possible Cretaceous / Tertiary boundary impact crater on the Yucatan Peninsula, Mexico |
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| Auteur | Hildebrand, A R; Penfield, G T; Kring, D A; Pilkington, M; Camargo Z, A; Jacobsen, S B; Boynton, W V |
| Source | Geology vol. 19, no. 9, 1991 p. 867-871, https://doi.org/10.1130/0091-7613(1991)019<0867:ccapct>2.3.co;2 |
| Année | 1991 |
| Séries alt. | Commission géologique du Canada, Contributions aux publications extérieures 31891 |
| Éditeur | Geological Society of America |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/0091-7613(1991)019<0867:ccapct>2.3.co;2 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Région | Yucatán Peninsula |
| Lat/Long OENS | -92.0000 -86.0000 22.0000 18.0000 |
| Sujets | cratères; cratères météoriques; anomalies gravimétriques; anomalies magnétiques; levés magnétiques; levés géophysiques; andésites; roches ignées; analyses des éléments majeurs; analyses géochimiques;
géologie extraterrestre; géochimie; géophysique; Tertiaire; Mésozoïque; Crétacé; Cénozoïque |
| Illustrations | diagrammes; échelles stratigraphiques; photographies; tableaux |
| Diffusé | 1991 01 01 |
| Résumé | (disponible en anglais seulement)
We suggest that a buried 180-km-diameter circular structure on the Yucata´n Peninsula, Mexico, is an impact crater. Its size and shape are revealed by magnetic
and gravity-field anomalies, as well as by oil wells drilled inside and near the structure. The stratigraphy of the crater includes a sequence of andesitic igneous rocks and glass interbedded with, and overlain by, breccias that contain evidence of
shock metamorphism. The andesitic rocks have chemical and isotopic compositions similar to those of tektites found in Cretaceous/Tertiary (K/T) ejecta. A 90-m-thick K/T boundary breccia, also containing evidence of shock metamorphism, is present 50
km outside the crater's edge. This breccia probably represents the crater's ejecta blanket. The age of the crater is not precisely known, but a K/T boundary age is indicated. Because the crater is in a thick carbonate sequence, shock-produced CO2
from the impact may have caused a severe greenhouse warming. |
| GEOSCAN ID | 132161 |
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