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UC Berkeley scientists have obtained more precise dates for the Deccan Traps volcanic lava flows, linking peak activity more closely to the asteroid or comet impact 66 million years ago and the coincident mass extinction. But if greenhouse gases emitted before the impact created a hothouse climate that set life up for a fall when the impact cooled the planet, those gases did not coincide with the largest lava flows from the Deccan Traps. 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...

More than 65 million years ago, a six-mile wide asteroid smashed into Mexico's Yucatán peninsula, triggering earthquakes, tsunamis and an explosion of debris that blanketed the Earth in layers of dust and sediment. Now analysis of commercial oil drilling data—denied to the academic community until recently—offers the first detailed look at how the Chicxulub impact reshaped the Gulf of Mexico. Figuring out what happened after these types of impacts gives researchers a better idea of how they redistribute geological material around the world. It also gives scientists an idea of what to expect if another such impact were to occur...

The age of the dinosaurs ended 66 million years ago, when an asteroid six miles in diameter crashed into what is now southeastern Mexico. The world went up in flames. Dinosaurs, along with the massive reptiles that ruled the sea and the sky, perished as forest fires raged across the globe, dust blotted out the sun, and Earth experienced intense heat, frigid cooling, and then more heat. Conventional wisdom states that mammalian diversity emerged from the ashes of the mass extinction, ultimately giving rise to our own humble species. But according to a study in the Journal of Evolutionary Biology,...

KT Boundary and Iridium Ever dreamt of hiking over the landscape and finding a mineral vein rich with ores, perhaps even silver or gold glittering in the sunshine, like in the Hand of Faith vein in Australia? How about joining the gold rush fever—without trekking up the Chilkoot Pass as thousands of prospectors did well over 100 years ago? The chances of finding a “mother lode” are slim, even when trying hard. They are similar to winning the jackpot in a big lottery. But don’t give up just yet; there is a new “horizon” for your exploration activity—the new frontiers...

Study of fossil shells solves unanswered question of how deep sea creatures survived asteroid strike during immense upheaval of the world's oceans... Like the dinosaurs themselves, giant marine reptiles, invertebrates and microscopic organisms became extinct after the catastrophic asteroid impact in an immense upheaval of the world's oceans, yet deep sea creatures managed to survive. This has puzzled researchers as it is widely believed that the asteroid impact cut off the food supply in the oceans by destroying free-floating algae and bacteria. However, in a study published in the April issue of the journal Geology, a team led by researchers...

Impact cratering is one of the most fundamental geological processes. On many planets, impact craters are the dominant geological landform. On Earth, erosion, plate tectonics, and volcanic resurfacing continually destroy the impact cratering record, but even here, the geological, biological, and environmental effects of impact cratering are apparent. Impact events are destructive and have been linked to at least one of the 'big five' mass extinctions over the past 540 million years. Intriguingly, impact craters can also have beneficial effects. Many impact craters are associated with economic metalliferous ore deposits and hydrocarbon reservoirs. This Special Paper from The Geological...

Sometimes we make that first dash into the ocean on summer vacation and happily announce, "It's warm as bathwater." But a new study based on ancient sediments collected off South America indicates that the tropical Atlantic Ocean really did hit temperatures as high as 107 degrees Fahrenheit back when dinosaurs ruled. The finding, reported Friday by researchers from the Woods Hole Oceanographic Institution during the annual meeting of the American Association for the Advancement of Science, also estimates that carbon dioxide made up as much as six times more of the atmosphere at that time than it does today.

A recently discovered fossilized footprint shows that dinosaurs once roamed in what is now a national park in Alaska, scientists said on Tuesday. The footprint, estimated to be 70 million years old, was discovered on June 27, the first evidence of dinosaurs ever found in Denali National Park and Preserve, the National Park Service said. The find was made by a University of Alaska Fairbanks student attending a field camp in the park. The three-toed track, six inches wide and nine inches long, appears to be from the left foot of a therapod, a class of two-legged predators, said Anthony...

Maine Crater Related to Dino-Killer Asteroid? By Larry O'Hanlon, Discovery News April 3, 2003 — The evidence is still skimpy, but there is a chance that the dino killer asteroid was not alone when it walloped the Earth 65 million years ago. A possible second crater, at least as big or bigger than the famous Chicxulub crater off Mexico's Yucatan peninsula, may have been created by a second hit moments after Chicxulub and off the coast of Maine. "It probably is a crater, but we really don't have age data," said marine geologist Dallas Abbott Lamont-Doherty Earth Observatory at Columbia...

The dinosaurs were wiped out 65 million years ago by at least two meteorite impacts, rather than a single strike, a new study suggests.Previously, scientists had identified a huge impact crater in the Gulf of Mexico as the event that spelled doom for the dinosaurs. Now evidence for a second impact in the Ukraine has been uncovered. This raises the possibility that the Earth may have been bombarded by a whole shower of meteorites. The new findings are published in the journal Geology by a team lead by Professor David Jolley of Aberdeen University. When first proposed in 1980, the...

EGS-AGU-EUG Joint Assembly, Nice, April 2003 Mass-extinction controversy flares again Core from asteroid crater fuels debate on what wiped out the dinosaurs. 10 April 2003 REX DALTON [photo] The dinosaurs were wiped out 65 million years ago. © alamy.com A claim that the asteroid that struck Mexico 65 million years ago did not cause the mass extinction that wiped out dinosaurs triggered heated debate at a meeting this week. The announcement is based on preliminary analysis of the first core drilled into the 185-kilometre Chicxulub asteroid crater near the Yucatan Peninsula. Gerta Keller of Princeton University in New Jersey says...