Chicxulub Crater: A possible Cretaceous/Tertiary boundary impact crater on the Yucatán Peninsula, Mexico

Analyses of shocked quartz at the global K-P boundary indicate an origin from a single, high-angle, oblique impact at Chicxulub

“…For impact angles of greater than ~15 degrees near-circular craters are produced and, for oblique impact angles up to ~45 degrees, ejecta is missing in the uprange direction [21]. Chicxulub is roughly circular [9,20], suggesting an impact angle of > 15 degrees.…”

“…The impact size and target chemistry are now reasonably well constrained [e.g. 9,20], but the obliquity of impact is unknown.…”

“…The K-P layer also contains highly shocked terrestrial minerals (quartz, feldspar and zircon) that originated from rocks at the impact site, as well as impact-derived Ni-rich spinel [2][3][4][5][6][7][8]. After the Chicxulub impact crater was discovered [9] numerous studies of this crater and the K-P boundary led to widespread agreement that Chicxulub was the site of a K-P boundary impact, with a few notable exceptions [10][11]. The cause of the K-P mass extinction is still contentious, and the precise role of the Chicxulub impact and Deccan volcanism remains a matter of some debate [e.g.…”

Geochemical evidence for combustion of hydrocarbons during the K-T impact event

“…65 Ma (1) and that the Chicxulub crater on the Yucatan Peninsula in Mexico is the most likely K-T impact structure (2). Initial results from a nonmarine K-T site nearest to the impact crater showed evidence of wildfires in the latest Cretaceous and early Paleocene coals but nothing unusual in the K-T BIRs (3).…”

Special Issue: Abstracts From the 2008 Issol Meeting

“…We take the collisional ejection process of the Chicxulub crater event (Hildebrand et al 1991) as Earth origin. If we assume the appropriate size of the meteorites (<1 cm in diameter), the number of meteorites to reach the Gl 581 system could be much greater than one.…”