| Titre | Seismic images of Chicxulub impact melt sheet and comparison with the Sudbury structure
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| Auteur | Barton, P J; Grieve, R A F; Morgan, J V; Surendra, A T; Vermeesch, P M; Christeson, G L; Gulick, S P S; Warner, M R |
| Source | Large meteorite impacts and planetary evolution IV; par Reimold, W U (éd.); Gibson, R L (éd.); Geological Society of America, Special Paper no. 465, 2010 p. 103-113, https://doi.org/10.1130/2010.2465(07) |
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| Année | 2010 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20080730 |
| Éditeur | Geological Society of America |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/2010.2465(07) |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Région | Chicxulub |
| Lat/Long OENS | -89.5333 -89.5000 21.4167 21.3833 |
| Sujets | cratères; cratères météoriques; morphologie; levés de reflexion sismiques; levés sismiques; interpretations sismiques; levés de refraction sismiques; Cratère d'impact de Chicxulub Impact; géologie
extraterrestre |
| Illustrations | cartes de localisation; profils sismiques; graphiques |
| Diffusé | 2010 11 24 |
| Résumé | (disponible en anglais seulement)
Chicxulub is the only known impact structure with a fully preserved peak ring on Earth and forms an important natural laboratory for the study of large craters
and understanding of large-scale cratering on Earth and other planets. Seismic data collected in 1996 and 2005 reveal detailed images of the uppermost crater in the central basin at Chicxulub. Seismic reflection profiles show a reflective layer about
1 km beneath the apparent crater floor, topped by upwardly concave reflectors interpreted as saucer-shaped sills. The upper part of this reflective layer is coincident with a thin high-velocity layer identified by analysing refractions on the 6 km
seismic streamer data. The high-velocity layer is almost horizontal and appears to be contained within the peak ring structure. We argue that this reflective layer is the predicted coherent melt sheet formed during impact, and may be comparable with
the unit known as the Sudbury Igneous Complex at the Sudbury impact structure. The Sudbury Igneous Complex, interpreted as a differentiated impact melt sheet, appears to have a similar scale and geometry, and an uppermost lithological sequence with a
velocity high at the top and a velocity inversion beneath. This comparison suggests that Chicxulub crater also contains a coherent differentiated melt sheet. |
| GEOSCAN ID | 226641 |
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