More & more epicycles!!!
Posted on 10/30/2007 1:31:46 PM PDT by crazyshrink
Dinosaur Deaths Outsourced to India? Boulder, CO, USA - A series of monumental volcanic eruptions in India may have killed the dinosaurs 65 million years ago, not a meteor impact in the Gulf of Mexico. The eruptions, which created the gigantic Deccan Traps lava beds of India, are now the prime suspect in the most famous and persistent paleontological murder mystery, say scientists who have conducted a slew of new investigations honing down eruption timing.
"It's the first time we can directly link the main phase of the Deccan Traps to the mass extinction," said Princeton University paleontologist Gerta Keller. The main phase of the Deccan eruptions spewed 80 percent of the lava which spread out for hundreds of miles. It is calculated to have released ten times more climate altering gases into the atmosphere than the nearly concurrent Chicxulub meteor impact, according to volcanologist Vincent Courtillot from the Physique du Globe de Paris.
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. At Rajahmundry there are two lava "traps" containing four layers of lava each. Between the traps are about nine meters of marine sediments. Those sediments just above the lower trap, which was the mammoth main phase, contain the incriminating microfossils.
Keller and her collaborator Thierry Adatte from the University of Neuchatel, Switzerland, are scheduled to present the new findings on Tuesday, 30 October, at the annual meeting of the Geological Society of America in Denver. They will also display a poster on the matter at the meeting on Wednesday, 31 October.
Previous work had first narrowed the Deccan eruption timing to within 800,000 years of the extinction event using paleomagnetic signatures of Earth's changing magnetic field frozen in minerals that crystallized from the cooling lava. Then radiometric dating of argon and potassium isotopes in minerals narrowed the age to within 300,000 years of the 65-million-year-old Cretaceous-Tertiary (a.k.a. Cretaceous-Paleogene) boundary, sometimes called the K-T boundary.
The microfossils are far more specific, however, because they demonstrate directly that the biggest phase of the eruption ended right when the aftermath of the mass extinction event began. That sort of clear-cut timing has been a lot tougher to pin down with Chicxulub-related sediments, which predate the mass extinction.
"Our results are consistent and mutually supportive with a number of new studies, including Chenet, Courtillot and others (in press) and Jay and Widdowson (in press), that reveal a very short time for the main Deccan eruptions at or near the K-T boundary and the massive carbon dioxide and sulfur dioxide output of each major eruption that dwarfs the output of Chicxulub," explained Keller. "Our K-T age control combined with these results strongly points to Deccan volcanism as the likely leading contender in the K-T mass extinction." Keller's study was funded by the National Science Foundation.
The Deccan Traps also provide an answer to a question on which Chicxulub was silent: Why did it take about 300,000 years for marine species to recover from the extinction event? The solution is in the upper, later Deccan Traps eruptions.
"It's been an enigma," Keller said. "The very last one was Early Danian, 280,000 years after the mass extinction, which coincides with the delayed recovery."
Keller and her colleagues are planning to explore the onset of the main phase of Deccan volcanism, that is, the rocks directly beneath the main phase lavas at Rajahmundry. That will require drilling into the Rajahmundry Traps, a project now slated for December-January 2007/2008.
Oops...didn’t see your comment before posting.
Shiva is still quite popular. I was just in a discussion of it over lunch yesterday, along with the other topics I mentioned above.
Thanks:)
Shiva impact was an interesting link. I now have several thoughts. I have seen other reports that oil has been found around impact sites, so the restrictions placed on studying the Shiva area by oil companies may be indicative. The fact that the Reunion Hot Spot may have been active in the Deccan area and then ramped up in 65 mya, could have been an antipodal effect from the Yucatan event. On the other hand the very thick iridium layer in India suggest that somethink happened nearby. The Gubbio layer in Italy was quite thin, and I have not heard of any other Iridium layer anything like as thick as that. As we observed with Shumacker Levy comet, there can be multiple strikes as the article mentioned as possibilities.
The Chesapeake Meteor of 34 mya was 50 miles in diameter, another crater off Toms River, NJ was 9 miles, and one in Russia named Popigai (sp?) was 60 miles in diameter. All roughly the same age. It is a shame that Chatterjee has not published, although if he can’t get at the site, perhaps that is understandable.
Can’t explain how alligators, etc. survived.
One of my theories is that the impact would have caused major oxone depletion and large open air daytime animals would have died from skin cancer, and related phenomena. Alligators and crocs spend a lot of time under water or hidden in embankments, likewise turtles. Birds and bees have feathers or hair, mammals have hair. Dinosaurs likely had exposed skin. There may also have been severe weather which added to the problems. Ice would have protected creatures under it from skin damage.
The Gubbio layer in Italy was quite thin, and I have not heard of any other Iridium layer anything like as thick as that.The significance of the iridium in the Gubbio layer is, it's thousands of miles from the impact site; the iridium is still greatly enriched, and not just there -- spread over a good bit of the Earth, meaning there was a very great big lot of it in the impactor. The quantity and the distribution of it cinched the ET origin. Iridium has also been found from the Eltanin impact circa 2 million years ago.
Because according to Liberal Logic, us rubes are too stupid to realize their brilliance, so they have to come up with really scary scenarios to scare us into letting them have control. They do this with Global Warming (see Al Gore's Why it's OK to Lie on Global Warming) and they tried to do this with the Dinosaurs. "If nuclear winter killed the dinosaurs just think what it will do to your children so you must join us to stop Ronald Reagan!!!"
Another similarity to global warming
Global Warming proponents want us to believe that even though at other times the sun drove climate change and CO2 never did, this time CO2 is driving the climate and the sun has no effect
and
The Asteroid proponents want us to believe that even though at other times massive volcanoes caused mass extinctions and other asteroid impacts (even bigger ones than the alledged Chixilub impact) never did, this time an asteroid caused the mass extinction and the 2nd largest volcanic event in world history had no effect.
More & more epicycles!!!
hehehe...unavailability of geologic information because of the oil companies’ restrictions was another discussion topic!
Epicycles were dreamed up to explain observations. Impact chains have been observed.
a little more.
Earth’s volcanism linked to meteorite impacts
Kate Ravilious
14:31 13 December 02
New Scientist
http://www.newscientist.com/news/news.jsp;jsessionid=MBJHENLAMHGN?id=ns99993171
Nope, not me. Sounds fun though.
Any chance Chicxulub and Shiva are concurrent markers of a whole-earth pass-through (e.g. or i.e., small black hole)?
Nah. There have been different ideas about what nudges loose the asteroids, including a dark companion of the Sun, the periodic trip through the galaxy, passing stars, and supernovae. My view is, there’s just a bunch of debris all the time, and eventually (think of the old Spirograph toy) they cross our path, or during repeated approaches, the Earth gives them the old come-hither.
You beat me to it. Earthquakes ring like a gong to the other side of the earth. It seems as though an asteroid impact could release enough energy that not quite unstable volcanic geology could become completely unstable.
Gosh, it must have been caused by millions of years of volcanic caldera collapses. /smirkAn Antarctic Bone BedW. Zinsmeister was accustomed to scoff at the idea that the Age of Dinosaurs ended violently with the impact of a giant asteroid some 65 million years ago. He always asked: "Where's the layer of burnt and twisted dinosaur bones?" His certainty was shaken, however, when he began mapping fossil deposits on Seymour Island, Antarctica. He didn't find the dinosaur bones but rather a giant bed of fish bones at least 50 square kilometers in area. Some sort of catastrophe must have annihilated untold millions of fish. And guess what? This great bone bed was deposited directly on top of that layer of extraterrestrial iridium that marks the 65-million-year-old Cretaceous Tertiary boundary at many sites around the world.
William R. Corliss
Science Frontiers
No. 104: Mar-Apr 1996
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