Chicxulub IODP-ICDP deep drilling: from cratering to mass extinction

About 66 million years ago, a 10 km asteroid or comet fragment collided at high velocity with Earth. The energy generated was equivalent to 5 billion Hiroshima bombs, and a huge crater formed within the crust of what is now Yucatan. The aftermath of this impact likely led to the dinosaur demise and the mass extinction of 60% of the fauna and flora on Earth. The resulting Chicxulub crater is unique because of its size (200 km), preservation, continuous ejecta sequence and possible effect on the biosphere. It forms also a great case-study to understand cratering on other planets, such as Mars or the Moon. In 2016, the International Ocean Discovery Program and International Continental Scientific Drilling Program join forces to drill a 1.5 km well within Chicxulub that now lies buried 1-km deep under the Gulf of Mexico. The recovered core will sample the peak-ring, a poorly known central region of the crater composed of deep crustal rocks that bounced-back after the pressure generated by the shock waves was released. This project investigates the lithology within the crater to 1) unravel the cratering process, study the behavior of the target-rock that led to the formation of the enigmatic central peak-ring, and document the production of globally spread ejecta; 2) determine the energy transfer “crater to environment” and the mechanisms through which the released gases (CO2, SOx..), fine dust, melt-debris etc. transformed the Late Cretaceous environment and its biosphere.