Crater, Chicxulub

Figure 1.6 Impact frustration (a) the Chicxulub crater, seen as a three-dimensional gravity map, thought to be responsible for the extinction of the dinosaurs (b) the cratered surface of the Moon. (Reproduced from photos by courtesy of NASA)...

Hildebrand A. R., Penfield G. T., Kring D. A., PiUdngton D., Camargo A., Jacobsen S. B., and Boynton W. V. (1991) Chicxulub crater, a possible Cretaceous-Tertiary boundary... 

W. Alvarez, P. Claeys, and S.W. Kieffer, Emplacement of Cretaceous-Tertiary boundary shocked quartz from Chicxulub crater. Science 269, pp. 930-935 (1995). 

Before considering continental weathering further, we briefly discuss melt rock as a potential source of Sr. Chicxulub melt rock from a depth of 1.4 km below the center of the crater has a Sr concentration of 300 ppm and an isotopic ratio of 0.709 [20], with the result that 3 x 1015 moles Sr would be required to... 

J. Morgan, M. Warner, and the Chicxulub Working Group, Size and morphology of the Chicxulub impact crater, Nature 390, pp. 472-476 (1997). 

The end of the Cretaceous period is marked by a major extinction event. Though not as great as the extinction event at the end of the end of the Triassic period, as many as fifty percent of the Earth s species became extinct. Nevertheless it caused the demise of the dinosaurs and was the end of the age of reptiles. Why this event occurred is contentious but there may have been an asteroid impact which created the Chicxulub crater off the Yucatan peninsula, Mexico. The pterosams, many marine reptiles, some groups of foraminifera and ammonites also became extinct. 

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