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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...

An ancient dinosaur nursery - the oldest nesting site ever found - has been unearthed in an excavation at a site in South Africa. The 190-million-year-old nesting site of the prosauropod dinosaur Massospondylus reveals significant clues about the evolution of complex reproductive behaviour in early dinosaurs. It discover clutches of eggs, many with embryos, as well as tiny dinosaur footprints, providing the oldest known evidence that the hatchlings remained at the nesting site long enough to at least double in size. “This research project, which has been ongoing since 2005 continues to produce groundbreaking results and excavations continue. First it...

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...

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.

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...

"[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.

The popular theory that dinosaurs were wiped out by an asteroid 65million years ago has been challenged. It was believed the Chicxulub crater in Mexico was the 'smoking gun' of the mass extinction event. Molten droplets from the ancient asteroid impact were found just below the Cretaceous-Tertiary boundary - a geological layer of sediment linked with the extinction. But soil samples from the 112-mile wide crater show the impact predates the disappearance of the dinosaurs by about 300,000 years. The latest research has been published in the Journal of the Geological Society. Study author Professor Gerta Keller from Princeton University...

The world's biggest bang wiped out the dinosaurs in a cataclysm that swathed our planet in choking dust - or at least that is what many palaeontologists claim. Others say dinosaurs died out gradually as Earth's climate and geology changed. It sounds a typical academic dispute - but last week it erupted into open warfare. Allegations have been made of deceit and unethical behaviour. One scientist is even alleged to have held back inconvenient evidence. 'This affair has become an object lesson on how partisan and unethical the whole dinosaur controversy has become,' said Dr Norman MacLeod, keeper of palaeontology...

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...

Just as scientists thought they had nailed down the answer, the debate has been reopened. A team of scientists claims the widely accepted theory that the extinction was triggered by a huge asteroid thumping into Mexico 65m years ago, cannot be true. Evidence that a giant asteroid impact was the cause of the dinosaurs' demise first emerged in the 1980s. Scientists analysing ancient soils in Italy found that layers of clay from the end of the Cretaceous period, the time the dinosaurs vanished, were unusually rich in a heavy metal called iridium. Later evidence of the layer was found in...

September 15, 2003 Could an enormous volcanic eruption have killed the dinosaurs? Cardiff University -- The extinction of the dinosaurs -– thought to be caused by an asteroid impact some 65 million years ago –- was more likely to have been caused by a 'mantle plume' -– a huge volcanic eruption from deep within the earth's mantle, the region between the crust and the core of the earth. This theory, already supported by a significant body of geologists and palaeontologists, is strengthened by new evidence to be presented at an international conference at Cardiff University on 11-12 September. Research by...

Volcanic Eruptions, Not Meteor, May Have Killed The DinosaursRajahmundry Quarry. Keller's crucial link between the eruption and the mass extinction comes in the form of microscopic marine fossils that are known to have evolved immediately after the mysterious mass extinction event. The same telltale fossilized planktonic foraminifera were found at Rajahmundry near the Bay of Bengal, about 1000 kilometers from the center of the Deccan Traps near Mumbai. (Credit: Photo courtesy Gerta Keller) ScienceDaily (Oct. 30, 2007) — A series of monumental volcanic eruptions in India may have killed the dinosaurs 65 million years ago, not a meteor impact in...

A 65 million year old tsunami is still wreaking havoc in the scientific community, a New Mexico State University professor says. The 300-foot-tall tsunami - an aftereffect of the giant meteor impact that some scientists think killed off the dinosaurs - scrambled fossils and rock and has made the event very hard to date, said Timothy Lawton, head of NMSU's geology department.

Scientists may have destroyed the well-established theory that a single, massive asteroid strike killed off the dinosaurs 65 million years ago. New data suggests the Chicxulub crater in Mexico, supposedly created by the collision, predates the extinction of the dinosaurs by about 300,000 years. The controversy over what killed the dinosaurs may run and run The authors say this impact did not wipe out the creatures, rather two or more collisions could have been responsible. The report is published in Proceedings of the National Academy of Sciences. An international group of scientists led by Professor Gerta Keller, of Princeton University,...

Scientists probing a vast crater off Mexico's Yucatan peninsula questioned a popular theory about dinosaurs on Monday, saying the collision that formed the crater happened too far back in time to have caused their extinction by itself. Much evidence points to the idea that an asteroid or comet gouged the Earth around 65 million years ago, triggering volcanic and climate changes that eventually wiped out the dinosaurs. When the huge, mostly underwater crater was found off Yucatan, it seemed the perfect candidate. "Since the early 1990s the Chicxulub crater on Yucatan, Mexico, has been hailed as the smoking gun that...

Dinosaur discoveries wow Boston Sensational fossil discoveries were unveiled on Monday, including the most primitive wishbone yet found in a dinosaur. Also presented was an exquisite skull from a tiny crocodile that could help provide vital new evidence on when the landmasses of Africa and South America split to take up their current positions on the planet's surface. The finds were described by Paul Sereno, one of the world's leading dino hunters, at the annual meeting of the American Association for the Advancement of Science in Boston. Dr Sereno, from the University of Chicago, told the meeting that science was ...

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...

Volcanoes that erupted in India about 65 million years ago were instrumental in the extinction of dinosaurs, according to new research. For the last thirty years scientists have believed a giant meteorite that struck Mexico’s Yucatan Peninsula was responsible for the mass extinction of dinosaurs, the Daily Telegraph reported on Wednesday. But now Gerta Keller, a geologist at Princeton University, New Jersey, says fossilised traces of plants and animals dug out of low lying hills at El Penon in northeast Mexico show this event happened 300,000 years after the dinosaurs disappeared. Keller suggests that the massive volcanic eruptions at the...

Scientists have discovered a macabre death scene that took place 67 million years ago. The setting was a nest, in which a baby dinosaur had just hatched from an egg, only to face an 11-foot-long snake waiting to devour it. The moment was frozen forever when, apparently, the nest was buried in a sudden avalanche of mud or sand and everything was fossilized. Scientists have discovered a macabre death scene that took place 67 million years ago. The setting was a nest, in which a baby dinosaur had just hatched from an egg, only to face an 11-foot-long snake waiting...

Dinosaur Shocker By Helen Fields Neatly dressed in blue Capri pants and a sleeveless top, long hair flowing over her bare shoulders, Mary Schweitzer sits at a microscope in a dim lab, her face lit only by a glowing computer screen showing a network of thin, branching vessels. That’s right, blood vessels. From a dinosaur. “Ho-ho-ho, I am excite-e-e-e-d,” she chuckles. “I am, like, really excited.” After 68 million years in the ground, a Tyrannosaurus rex found in Montana was dug up, its leg bone was broken in pieces, and fragments were dissolved in acid in Schweitzer’s laboratory at North...