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The Alvarez hypothesis posits that the mass extinction of the non-avian dinosaurs and many other living things during the Cretaceous–Paleogene extinction event was caused by the impact of a large asteroid on the Earth. Prior to 2013, it was commonly cited as having happened about 65 million years ago, but Renne and colleagues (2013) gave an ...
Chicxulub crater. Chicxulub crater (Mexico) Free-air gravity anomaly over the Chicxulub structure (coastline and state boundaries shown as black lines) The Chicxulub crater (IPA: [t͡ʃikʃuˈluɓ] ⓘ cheek-shoo-LOOB) is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is offshore, but the crater is named after ...
Walter Alvarez (born October 3, 1940) is a professor in the Earth and Planetary Science department at the University of California, Berkeley. He and his father, Nobel Prize –winning physicist Luis Alvarez , developed the theory that dinosaurs were killed by an asteroid impact.
The Cretaceous–Paleogene (K–Pg) extinction event, [ a ] also known as the K–T extinction, [ b ] was the mass extinction of three-quarters of the plant and animal species on Earth [ 2 ][ 3 ] approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than 25 kilograms ...
Ursula Marvin argued that the asteroid impact explanation for the end-Cretaceous mass extinction was at odds with the idea of uniformitarianism and criticized those who attempt to reconcile the two as engaging in "newspeak". [95] Alvarez and Asaro measured the iridium levels of a 57m span of rock near the K–T boundary at Gubbio once more.
A team led by Luis Alvarez proposed in 1980 an extraterrestrial origin for this iridium, attributing it to an asteroid or comet impact. [77] Their theory, known as the Alvarez hypothesis , is now widely accepted to explain the extinction of the non-avian dinosaurs.
The climate across the Cretaceous–Paleogene boundary (K–Pg or formerly the K–T boundary) is very important to geologic time as it marks a catastrophic global extinction event. Numerous theories have been proposed as to why this extinction event happened including an asteroid known as the Chicxulub asteroid, volcanism, or sea level changes.
Luis Walter Alvarez (June 13, 1911 – September 1, 1988) was an American experimental physicist, inventor, and professor who was awarded the Nobel Prize in Physics in 1968 for his discovery of resonance states in particle physics using the hydrogen bubble chamber. [ 1 ] In 2007 the American Journal of Physics commented, "Luis Alvarez was one ...