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How is the Chicxulub crater connected to the mass extinction at the end of the Cretaceous Period?
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Meteorite crater
Four impact craters of the same size (30 km [20 miles] in diameter) imaged by spacecraft on different solid bodies of the solar system and reproduced at the same scale. They are (clockwise from upper left) Golubkhina crater on Venus, Kepler crater on the Moon, an unnamed crater on Jupiter's moon Ganymede, and an unnamed crater on Mars. The images are oriented such that the craters appear illuminated from the left; the Venusian crater is imaged in radar wavelengths, the others in visible light.
The Chicxulub crater is widely considered the site of the asteroid impact that triggered the K–T extinction event approximately 66 million years ago, resulting in the loss of about 80 percent of all species, including the dinosaurs.12
The connection between the impact and this mass extinction is supported by several catastrophic environmental consequences:
- Atmospheric Blockage: The impact ejected massive quantities of rock debris and dust into the atmosphere, enshrouding Earth in darkness for years or even decades. This prevented photosynthesis, causing the collapse of the food chain.32
- Climate Change: The release of sulfurous minerals created a global haze of sulfuric acid, potentially leading to acid rain and a significant drop in global temperatures.2
- Immediate Destruction: The collision triggered enormous tsunamis and widespread wildfires, causing immediate devastation across vast regions.32
Evidence for this link includes the presence of iridium—an element rare on Earth but common in meteorites—and tektites found in geological layers dating to the end of the Cretaceous Period.32