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Scientists have been trying to figure out what killed off the dinosaurs for decades. Most agree the asteroid or comet that struck the Yucatan Peninsula some 66 million years ago, the Chicxulub meteorite, played a significant role in snuffing them out, but the significance of the Deccan Traps eruptions has puzzled scientists. Now, new research -- published Monday -- suggests the volcanic activity had a significant impact on Earth's climate, and perhaps, on the dinosaurs, too. "For the first time, we can provide insights into the distinct climatic and environmental impacts of Deccan Traps volcanism by analyzing a single material,"...

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...

...But Keller doesn’t buy any of it. “It’s like a fairy tale: ‘Big rock from sky hits the dinosaurs, and boom they go.’ And it has all the aspects of a really nice story,” she said. “It’s just not true.” ...Keller’s resistance has put her at the core of one of the most rancorous and longest-running controversies in science. “It’s like the Thirty Years’ War,” says Kirk Johnson, the director of the Smithsonian’s National Museum of Natural History. Impacters’ case-closed confidence belies decades of vicious infighting, with the two sides trading accusations of slander, sabotage, threats, discrimination, spurious data, and...

A giant asteroid smashing into Earth is the only plausible explanation for the extinction of the dinosaurs, a global scientific team said on Thursday, hoping to settle a row that has divided experts for decades.

According to new research led by a University of Colorado at Boulder geophysicist, a giant asteroid that hit the coast of Mexico 65 million years ago probably incinerated all the large dinosaurs that were alive at the time in only a few hours, and only those organisms already sheltered in burrows or in water were left alive. The six-mile-in-diameter asteroid is thought to have hit Chicxulub in the Yucatan, striking with the energy of 100 million megatons of TNT, said chief author and Researcher Doug Robertson of the department of geological sciences and the Cooperative Institute for Research in Environmental...

LONDON (Reuters) - A giant asteroid smashing into Earth is the only plausible explanation for the extinction of the dinosaurs, a global scientific team said on Thursday, hoping to settle a row that has divided experts for decades. A panel of 41 scientists from across the world reviewed 20 years' worth of research to try to confirm the cause of the so-called Cretaceous-Tertiary (KT) extinction, which created a "hellish environment" around 65 million years ago and wiped out more than half of all species on the planet. Scientific opinion was split over whether the extinction was caused by an asteroid...

Caption: IU Bloomington geochemist Simon Brassell (right), Penn State sedimentologist Michael Arthur (middle), and Tohoku Univ. sedimentologist Harumasa Kano (left) inspect an ancient shale aboard the JOIDES Resolution research vessel. BLOOMINGTON, Ind. -- Ancient rocks from the bottom of the Pacific Ocean suggest dramatic climate changes during the dinosaur-dominated Mesozoic Era, a time once thought to have been monotonously hot and humid. In this month's Geology, scientists from Indiana University Bloomington and the Royal Netherlands Institute for Sea Research present new evidence that ocean surface temperatures varied as much as 6 degrees Celsius (about 11 degrees Fahrenheit) during the...

It's bad enough when, every few million years, an asteroid rocks our planet. It's worse if the impact triggers regional or global volcanic activity, which is not only hazardous to nearby plants and animals but can choke Earth's atmosphere with deadly gases for months or years. But there's also a possible bright side, like the birth of nice places like Hawaii. For more than three decades, scientists have explored the question of whether an asteroid impact could cause significant volcanic eruptions, hot spots that spring up out of nowhere and create new landforms or rearrange old ones. The process might...

Ancient mega-catastrophe paved way for the dinosaurs, spawned Australian continent. Planetary scientists have found evidence of a meteor impact much larger and earlier than the one that killed the dinosaurs -- an impact that they believe caused the biggest mass extinction in Earth's history.The 300-mile-wide crater lies hidden more than a mile beneath the East Antarctic Ice Sheet. And the gravity measurements that reveal its existence suggest that it could date back about 250 million years -- the time of the Permian-Triassic extinction, when almost all animal life on Earth died out.Its size and location -- in the Wilkes Land...

...disaster is “not imminent,” he adds, “This is the type of mechanism that may generate massive plume eruptions, but on the timescale of 100 million to 200 million years from now. So don’t cancel your cruises.”... Hotspot plume supervolcano eruptions like those during the past 2 million years at Wyoming’s Yellowstone caldera, which covered North America with volcanic ash.Gargantuan flood basalt eruptions that created “large igneous provinces” like the Pacific Northwest’s Columbia River basalts 17 million to 15 million years ago, India’s Deccan Traps some 65 million years ago and the Pacific’s huge Ontong Java Plateau basalts, which buried an...

An apparent crater as big as Ohio has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago. The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs. The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward, the researchers said. "This...

Here, for the first time (to our knowledge), we are able to demonstrate unambiguously that the impact at the Cretaceous–Paleogene boundary (K–Pg, ∼66 Mya) was followed by a so-called “impact winter.” This impact winter was the result of the injection of large amounts of dust and aerosols into the stratosphere and significantly reduced incoming solar radiation for decades. Therefore, this phase will have been a key contributory element in the extinctions of many biological clades, including the dinosaurs. The K–Pg boundary impact presents a unique event in Earth history because it caused global change at an unparalleled rate. This detailed...

Geoscientists now overwhelmingly agree that a single large asteroid or comet impact, such as Chicxulub in the Yucatan peninsula of Mexico, could not have been the sole cause of the end-Cretaceous mass extinction. Instead, new research in both planetary/space science and multiple earth-science specialties reveals that concomitant volcanic activity and the associated climate and environmental changes were significant contributing factors in four of the five major mass extinctions in Earth history.

Earth's volcanism linked to meteorite impacts 14:31 13 December 02 Exclusive from New Scientist Print EditionSpace rocks are blamed for violent eruptions (Image: GETTY) Large meteorite impacts may not just throw up huge dust clouds but also punch right through the Earth's crust, triggering gigantic volcanic eruptions. The idea is controversial, but evidence is mounting that the Earth's geology has largely been driven by such events. This would also explain why our planet has so few impact crater remnants. Counting the number of asteroids we see in the sky suggests that over the past 250 million years, Earth should have...

The asteroid that slammed into the ocean off Mexico 66 million years ago and killed off the dinosaurs probably rang the Earth like a bell, triggering volcanic eruptions around the globe that may have contributed to the devastation, according to a team of University of California, Berkeley, geophysicists. Specifically, the researchers argue that the impact likely triggered most of the immense eruptions of lava in India known as the Deccan Traps, explaining the "uncomfortably close" coincidence between the Deccan Traps eruptions and the impact, which has always cast doubt on the theory that the asteroid was the sole cause of...

A definitive geological timeline shows that a series of massive volcanic explosions 66 million years ago spewed enormous amounts of climate-altering gases into the atmosphere immediately before and during the extinction event that claimed Earth's non-avian dinosaurs, according to new research from Princeton University. A primeval volcanic range in western India known as the Deccan Traps, which were once three times larger than France, began its main phase of eruptions roughly 250,000 years before the Cretaceous-Paleogene, or K-Pg, extinction event, the researchers report in the journal Science. For the next 750,000 years, the volcanoes unleashed more than 1.1 million cubic...

When a scientific principle is common knowledge even in grammar school, you know it has long since crossed the line from theory to established fact. That's the case with dinosaur extinction. Some 65 million years ago — as we've all come to know — an asteroid struck the earth, sending up a cloud that blocked the sun and cooled the planet. That, in turn, wiped out the dinosaurs and made way for the rise of mammals. The suddenness with which so many species vanished after that time always suggested a single cataclysmic event, and the 1978 discovery of a 112-mile,...

Source: Geological Society of America Date: October 24, 2006 Far More Than A Meteor Killed Dinos, Evidence Suggests There's growing evidence that the dinosaurs and most their contemporaries were not wiped out by the famed Chicxulub meteor impact, according to a paleontologist who says multiple meteor impacts, massive volcanism in India, and climate changes culminated in the end of the Cretaceous Period. Cottonmouth Creek waterfall over the event deposit with reworked Chicxulub impact spherules. The original Chicxulub ejecta layer was discovered in a yellow clay layer 45 cm below the base of the event deposit. The yellow clay represents a...

Impact didn't lead to mass extinction 65 million years ago, geologists findThe enduringly popular theory that the Chicxulub crater holds the clue to the demise of the dinosaurs, along with some 65 percent of all species 65 million years ago, is challenged in a paper to be published in the Journal of the Geological Society on April 27, 2009. The crater, discovered in 1978 in northern Yucutan and measuring about 180 kilometers (112 miles) in diameter, records a massive extra-terrestrial impact. When spherules from the impact were found just below the Cretaceous-Tertiary (K-T) boundary, it was quickly identified as the...

"[The theory] is essentially a more eloquent way of saying what I and many other palaeontologists have been saying for many years," says Professor Gerta Keller of Princeton University. "Namely that the impact-kill hypothesis is all wrong. Impacts alone could not have been the killing mechanism for the K-T [Cretaceous-Tertiary event] or any of the other major mass extinctions." ... "I'm very happy they have done the analysis based on the literature and come up with the same conclusions that palaeontologists have been preaching all along," Keller says.