by Geological Society of America, July 14, 2020 in ScienceDaily
The impact event that formed the Chicxulub crater (Yucatán Peninsula, México) caused the extinction of 75% of species on Earth 66 million years ago, including non-avian dinosaurs. One place that did not experience much extinction was the deep, as organisms living in the abyss made it through the mass extinction event with just some changes to community structure.
New evidence from International Ocean Discovery Program (IODP) Expedition 364 of trace fossils of burrowing organisms that lived in the seafloor of the Chicxulub Crater beginning a few years after the impact shows just how quick the recovery of the seafloor ecosystem was, with the establishment of a well-developed tiered community within approximately 700,000 years after the event.
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by Nirmal Narayanan, November 30, 2019 in InternationalBusinessTimes
Several space experts believe that earth will face an extinction event following a dreaded asteroid hits
It was on last July that NASA discovered a giant asteroid named 2019 ND7. This doomsday rock is more than 200 meters wide, and a potential hit on the planet could wipe out a city within a fraction of a second. Experts believe that a potential collision with 2019 ND7 will unleash energy equivalent to more than 1,000 atomic bombs exploded in Hiroshima during World War II, and millions of people will lose life instantly.
However, the chances of asteroid 2019 ND7 hitting the earth are very small. The United States space agency has calculated the risk at 1 in 310,000, which means there is a 99.99968 chance that this dangerous space rock will miss the earth. 2019 WG2 is a small asteroid when compared to 2019 ND7.
The asteroid is 35 meters wide, and NASA has calculated the risk at 1 in 4,000. As per NASA, 2019 ND7 may crash into the earth between 2097-2117 on 20 different occasions. On the other hand, 2019 WG2 may hit between 2098 and 2119 on 56 different occasions.
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by Univ. of California – Berkeley, February 21, 2019 in ScienceDaily
Based on new data published today in the journal Science, it seems increasingly likely that an asteroid or comet impact 66 million years ago reignited massive volcanic eruptions in India, half a world away from the impact site in the Caribbean Sea.
But it leaves unclear to what degree the two catastrophes contributed to the near-simultaneous mass extinction that killed off the dinosaurs and many other forms of life.
The research sheds light on huge lava flows that have erupted periodically over Earth’s history, and how they have affected the atmosphere and altered the course of life on the planet.
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La géologie, une science plus que passionnante … et diverse
