Alvarez event
Alvarez event The collision of a giant meteorite with the earth 65 million years ago that caused catastrophic changes to the earth's climate and environment and a mass extinction of species, including the dinosaurs. This hypothesis was advanced in 1980 by the US physicist Luis Walter Alvarez (1911–88) and his geologist son Walter Jr, based on the unusually high concentration of the element iridium in a thin layer of clay deposited at the end of the Cretaceous (see iridium anomaly). This clay marks the boundary between the Cretaceous period and the more recent Tertiary (the so-called K–T boundary). Subsequently, geologists discovered a possible impact crater, roughly 160 km in diameter, along the coast of eastern Mexico, and other evidence has tended to support the hypothesis. Such a collision would have produced a massive tidal wave and fireball and sent a vast cloud of rock and other debris into the atmosphere. The resulting upheaval in the climate is estimated to have caused the extinction of some 75% of all species.
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Extinction , Extinction is the permanent disappearance of an entire species. (A species is a group of closely related, physically similar living organisms that ca… Mass Extinction , Extinction , the death of all members of a species , is a natural process that has been occurring since the beginning of life on Earth . Nearly all s… Paleocene Epoch , In geologic time , the Paleocene Epoch occurs during the Tertiary Period (also sometimes divided or referred to in terms of a Paleogene Period and a… Cretaceous-tertiary Boundary , Cretaceous-Tertiary boundary
K/T boundary event
K/T boundary event The impact of an asteroid, about 10–11 km in diameter, that struck the Earth about… Biogeography , An enormous variety of species live in the thin layer on Earth's surface that makes up the biosphere. None of these species is found everywhere on Ea… Megathermal Climate , Skip to main content
megathermal climate
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Alvarez event