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The date of the impact coincides precisely with the Cretaceous–Paleogene boundary (K–Pg boundary), slightly more than 66 million years ago. [7] The crater is estimated to be over 150 km (93 mi) in diameter [10] and 20 km (12 mi) in depth, well into the continental crust of the region of about 10–30 km (6.2–18.6 mi) depth.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out, widely thought to have been caused by the impact of a large asteroid that formed the Chicxulub crater in the Gulf of Mexico.
The Chicxulub impact has been widely considered the most likely cause for the Cretaceous–Paleogene mass extinction, with some scholars linking other impacts like the Popigai impact in Russia and the Chesapeake Bay impact to later extinction events, though the causal relationship has been questioned.
Because the Raton Formation is a well-preserved sequence of rocks spanning the Cretaceous-Paleogene boundary, it has been studied for evidence of a large meteor impact at the end of the Cretaceous that is thought to have caused the Cretaceous–Paleogene extinction event. The boundary is represented by a 1-cm thick tonstein clay layer which has ...
The Cretaceous–Paleogene extinction event (formerly known as the Cretaceous–Tertiary extinction event) [a] occurred at the end of this age. [3] In this mass extinction , many commonly recognized groups such as non-avian dinosaurs , plesiosaurs and mosasaurs , as well as many other lesser-known groups, died out.
Pérez-Díaz concludes that the accelerated movement of the Indian plate is an illusion wrought by large errors in geomagnetic reversal timing around the Cretaceous–Paleogene boundary, and that a recalibration of the time scale shows no such acceleration exists. [18] [19]
Insular India was an isolated landmass which became the Indian subcontinent.Across the latter stages of the Cretaceous and most of the Paleocene, following the breakup of Gondwana, the Indian subcontinent remained an isolated landmass as the Indian Plate drifted across the Tethys Ocean, forming the Indian Ocean.
In 1980, a team of researchers consisting of Nobel Prize-winning physicist Luis Alvarez, his son, geologist Walter Alvarez, and chemists Frank Asaro and Helen Michel discovered that sedimentary layers found all over the world at the Cretaceous–Paleogene boundary contain a concentration of iridium many times greater than normal (30, 160, and ...