Posted on 10/15/2009 10:07:58 AM PDT by decimon
Boulder, CO, USA -- A mysterious basin off the coast of India could be the largest, multi-ringed impact crater the world has ever seen. And if a new study is right, it may have been responsible for killing the dinosaurs off 65 million years ago.
Sankar Chatterjee of Texas Tech University and a team of researchers took a close look at the massive Shiva basin, a submerged depression west of India that is intensely mined for its oil and gas resources. Some complex craters are among the most productive hydrocarbon sites on the planet. Chatterjee will present his research at this month's Annual Meeting of the Geological Society of America in Portland, Oregon.
“If we are right, this is the largest crater known on our planet,” Chatterjee said. “A bolide of this size, perhaps 40 kilometers (25 miles) in diameter creates its own tectonics.”
By contrast, the object that struck the Yucatan Peninsula, and is commonly thought to have killed the dinosaurs was between 8 and 10 kilometers (5 and 6.2 miles) wide.
It's hard to imagine such a cataclysm. But if the team is right, the Shiva impact vaporized Earth's crust at the point of collision, leaving nothing but ultra-hot mantle material to well up in its place. It is likely that the impact enhanced the nearby Deccan Traps volcanic eruptions that covered much of western India. What's more, the impact broke the Seychelles islands off of the Indian tectonic plate, and sent them drifting toward Africa.
The geological evidence is dramatic. Shiva's outer rim forms a rough, faulted ring some 500 kilometers in diameter, encircling the central peak, known as the Bombay High, which would be 3 miles tall from the ocean floor (about the height of Mount McKinley). Most of the crater lies submerged on India's continental shelf, but where it does come ashore it is marked by tall cliffs, active faults and hot springs. The impact appears to have sheared or destroyed much of the 30-mile-thick granite layer in the western coast of India.
The team hopes to go India later this year to examine rocks drill from the center of the putative crater for clues that would prove the strange basin was formed by a gigantic impact.
“Rocks from the bottom of the crater will tell us the telltale sign of the impact event from shattered and melted target rocks. And we want to see if there are breccias, shocked quartz, and an iridium anomaly,” Chatterjee said. Asteroids are rich in iridium, and such anomalies are thought of as the fingerprint of an impact. **WHEN & WHERE**
The significance of the contemporaneous Shiva impact structure and Deccan volcanism at the KT boundary Sunday, 18 October 2009, 3:45-4:00 p.m. Oregon Convention Center, Portland Ballroom 256
View abstract, at http://gsa.confex.com/gsa/2009AM/finalprogram/abstract_160197.htm. **CONTACT INFORMATION**
For on-site assistance during the 2009 Annual Meeting, 18-21 October, contact Christa Stratton in the Newsroom (7:30 a.m.-6:00 p.m. PDT), Oregon Convention Center, Room D133, +1-503-963-5708.
After the meeting contact: Sankar Chatterjee Geosciences, Texas Tech University MS Box 41053 Lubbock, Texas 79409-3191, USA +1-806-794-3287
Three-dimensional reconstruction of the submerged Shiva crater (~500 km diameter) at the Mumbai Offshore Basin, western shelf of India from different cross-sectional and geophysical data. The overlying 4.3-mile-tick Cenozoic strata and water column were removed to show the morphology of the crater.
If they were chips off of the same old block then that should be possible.
Thanks FN!
Jack, because, y’know, that’s the same as prince. ;’)
touche! you win.
Science changes with the FACTS. If new facts come in, they should change things. Are you suggesting they simply ignore new evidence, sweep it under the rug, slap their hands together and walk away?
There's a lot of new evidence that global warming isn't. Yet some politicians and some political scientists are ignoring it. That is far more disastrous to us all than changing with the new data.
At least don't confuse the majority of the true scientists with those in the minority who are prostituting themselves for grants proving political points.
Science no longer deals in theory. They assert that their theories ARE facts. Nowadays scientists theorize along leftist, politically correct lines and then often don’t even bother to do the research! Ask Peter Duesberg if there is any proof that HIV causes AIDS. Ask Lord Monckton what the proof is that humanity is causing Global Warming. These are examples of what I’m saying.
That’s just not true. You’re confusing science with what the journalists in the driveby media tell you is science.
Stop and think: Lord Monckton is also a scientist!
decimon ~ If they were chips off of the same old block then that should be possible.
Indeed. We know for a fact that this is possible from watching the Shoemaker-Levy 7 strikes on Jupiter.
At least those of us who believe in telescopes do...
Ah. I see you know Jack...
Thanks. I was thinking of that but couldn't come up with the name.
Yes, I believe that a large meteor struck off the coast of India, creating a very large crater.
Do you think the earth was created by God with this crater in place?
I think the problem is that scientists speak in certainties even when they know that they are dealing with a thinly tested theory. I’m sure the hedge much more in their papers that are printed in science journals but too often they come across as if they “know” something when they merely have some amount of evidence which leads them to believe something. I think this can be seen in everything from nutrition to global warming.
Yes, there are Freepers who believe that the earth is 6000 years old, that Adam and Eve lived among the dinosaurs (and that dino bones were put on earth by the old man in the sky to “fool us”).
Thought so...
dont know wasnt there
Really? And whats your explanation?
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