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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...

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...

A series of gargantuan volcanic eruptions may have ended at nearly the same time that the dinosaurs went extinct, a new study shows. The find bolsters a controversial theory that massive volcanism contributed to the global catastrophe known as the K-T extinction, which wiped out the dinosaurs and many of Earth's other organisms 65 million years ago. Gerta Keller, a Princeton University paleontologist, presented the new research last week at a meeting of the Geological Society of America in Denver, Colorado. She found that underwater portions of the ancient lava flows, known as the Deccan Traps, contained marine fossils only...

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...

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.

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...

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...

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...

Chelyabinsk, a large city in western Russia, was best known for producing tractors and professional hockey players until the morning of February 15, 2013, when a 19-meter-wide meteor screamed through the sky and exploded with the force of 500 kilotons of TNT. The meteor generated a fireball many times brighter than the sun, so powerful it even caused sunburns. The shock wave blew out windows and knocked residents off of their feet, injuring more than 1,200. The object was the largest to strike Earth in more than a century... Asteroids that come within 28 million miles of our planet are...

Geologist Wins Top Science Award March 6, 2006 10:00 p.m. EST Yvonne Lee - All Headline News Staff Reporter Reno, Nevada (AHN) - Geologist Walter Alvarez will receive the Desert Research Institute's silver medallion and a $20,000 prize. The Associated Press reports the University of California-Berkeley scientist came up with the theory that dinosaurs were killed off when a comet or asteroid crashed into the Earth. President of the institute Stephen G. Wells says, "Until the impact theory was finally proven, Dr. Alvarez and his colleagues were regarded as heretics by the `old guard' in the field of geology." In...

A fossil discovered in Montana has given new momentum to the hypothesis that dinosaurs were thriving right up until a devastating meteor hit Earth 65 million years ago, causing their extinction. Scientists from Yale University have found what is believed to be the youngest dinosaur fossil ever found, thought to be from just before the mass extinction took place. The discovery, described in a study published in the online edition of the journal Biology Letters, contradicts the theory that the dinosaurs slowly went extinct before the cosmic impact. The fossil -- a 45-centimetre horn believed to be from a triceratops...

Pterosaurs, flying reptiles from the time of the dinosaurs, were not driven to extinction by the birds, but in fact they continued to diversify and innovate for millions of years afterwards.A new study by Katy Prentice, done as part of her undergraduate degree (MSci in Palaeontology and Evolution) at the University of Bristol, shows that the pterosaurs evolved in a most unusual way, becoming more and more specialised through their 160 million years on Earth. The work is published today in the Journal of Systematic Palaeontology. ‘Usually, when a new group of animals or plants evolves, they quickly try out...

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...

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...

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...

Bacteria living on opposite sides of a canyon have evolved to cope with different temperatures by altering the make-up of their 'skin', or cell membranes. Scientists have found that bacteria change these complex and important structures to adapt to different temperatures by looking at the appearance of the bacteria as well as their genes. The researchers hope their study, published in the August issue of Microbiology, will start a new trend in research.

A suit of armor first worn by an African fish almost 100 million years ago to withstand ancient carnivores is today providing clues to engineers designing body armor for soldiers of the future. The armor of the fish, Polypterus senegalus, is so effective because it is a composite of several materials lined up in a certain way, the engineers state in a their analysis detailed in the July 27 issue of the journal Nature Materials. "Such fundamental knowledge holds great potential for the development of improved biologically inspired structural materials," said lead MIT researcher Christine Ortiz, "for example soldier, first-responder...

DINOSAURS were running out of evolutionary steam during their last 50 million years on Earth, scientists have learned. The reptiles were left behind in the "Cretaceous Terrestrial Revolution", 100 million years ago, that saw the massive proliferation of vegetation and many animals. While flowering plants, lizards, snakes, birds and mammals all evolved swiftly, dinosaurs plodded behind. A short time later, they were extinct. Researchers made the discovery after using computer programs to produce a "super-tree" of dinosaur lineages. The results showed the most likely pattern of evolution for 440 of the 600 known species of dinosaur. The findings, published in...