how did the dinosours die?
- mallimalar_2000Lv 71 decade agoFavorite Answer
Current ideas about dinosaur extinction all center about the impact theory. Below is some summary info you may find of interest:
K-T extinction event mystery may be solved.
The North American continent and many of its creatures were barbecued 65 million years ago in an immense, white-hot "corridor of incineration" resulting from an asteroid impact in Mexico, scientists say.
The theory, based partly on laboratory experiments at NASA's Ames Research Center in Mountain View, California, may solve an important mystery.
Over the last decade, many Earth scientists have accepted the theory that an asteroid, comet or bolide impact wiped out the non-avian dinosaurs and many other species 65 million years ago. The impact, which apparently occurred in Mexico's Yucatan Peninsula, may have triggered a global climate change that destroyed plant and animal life around the world.
However, a mystery emerged as more and more data was gathered supporting the theory. The fossil record showed that the impact event caused an unusually high number of extinctions in North America. Why?
A possible solution to the mystery appears in an article in the November 1996 issue of Geology by planetary geoscientist Peter H. Schultz of Brown University in Providence, Rhode Island, and paleocoeanographer Steven D'Hondt of the University of Rhode Island.
In the article they cite geological evidence that the asteroid or other object didn't strike the Yucatan head-on; rather, it approached from the southeast and hit at an angle, perhaps 20 to 30 degrees from the horizontal.
The impact forced the searing debris toward the northwest into a parabola-shaped kill zone over western and central North America. This "corridor of incineration," as Schultz and D'Hondt called it, may have ranged beyond the Pacific shore and the Appalachian Mountains, and possibly all the way to Siberia.
Schultz simulated the asteroid impact in lab experiments at NASA-Ames. He used a hypervelocity gas gun that fires projectiles (such as quarter-inch metallic spheres) at 4 miles per second at low angles toward targets resembling the Yucatan surface, "literally dirt or carbonates." The collisions generated extremely hot plasmas of ionized gas, "as hot as the sun's surface, up to 10,000 degrees Fahrenheit."
Creatures living at the time of the impact 65 million years ago, assuming they weren't actually in the kill zone, might have witnessed the following sequence of events:
A brilliant flash erupted in the southeast as the asteroid rammed into Mexico's Yucatan Peninsula, gouging out a crater about 120 miles wide and vaporizing the upper crust.
A brilliant, hot plume of vapor and incandescent "sun-bright" debris arced across the sky at about 7 to 10 miles per second, then crashed onto North America.
Scalding heat killed countless land-dwelling plants and animals. For example, 90 percent of known types of leaf-bearing trees and plants became extinct, according to the fossil record.
A slower yet still high-velocity cloud of dust, debris and molten material then swept over North America.
Finally, an hour or more after the impact, more dust began to fall from the sky, perhaps for days, as material was dispersed around the globe.
A few fish and other aquatic creatures may have survived in cool rivers, lakes and coastal waters, Schultz says. REFERENCES:
Asteroid mystery may be solved.
The Columbus Dispatch, 10 November, sec. A, 13.
More evidence for asteroid impact found.
Scientists drilling for core samples in the Atlantic Ocean announced Sunday, February 16, that they have found what they believe to be strong evidence of an asteroid impact 65 million years ago.
"We've got the smoking gun," said Richard D. Norris, leader of the international ocean drilling expedition that probed the Atlantic Ocean floor in search of asteroid evidence. "It is proof positive of the impact."
Robert W. Corell, assistant director for Geosciences of the National Science Foundation , said the core samples are the strongest evidence yet that an asteroid impact caused the K-T extinction.
Geologist Walter Alvarez of the University of California, Berkeley
first proposed in 1980 that the non-avian dinosaurs disappeared from the fossil record suddenly because of a massive asteroid hit. At first, the theory had few supporters.
But in 1989, scientists found evidence of a huge impact crater north of Chicxulub, on Mexico's Yucatan Peninsula. Later studies found evidence of debris washed out of the Gulf by waves that went inland as far as what is now Arkansas.
It's now widely believed that an asteroid of six to 12 miles in diameter smashed to Earth at thousands of miles an hour. It instantly gouged a crater 150 to 180 miles wide. That energy release was more powerful than if all of the nuclear weapons ever made were set off at once, said Norris. Billions of tons of soil, sulphur and rock vapor were lifted into the atmosphere, blotting out the sun. Recent studies suggest that the asteroid hit at a shallow angle, causing the debris to travel in a "parabola of death" that incinerated much of North America. Temperatures around the globe plunged.
Up to 70 percent of all species, including the non-avian dinosaurs, perished. Norris said the expedition recovered three core samples that have the unmistakable signature of an asteroid impact approximately 65 million years ago. The cores include a thin brownish layer that the scientists called the "fireball layer" because it is thought to contain remains of the actual asteroid itself.
The scientists, working on the drill ship Joides Resolution, spent five weeks off the east coast of Florida collecting cores from the ocean floor in about 8,500 feet of water. The team penetrated up to 300 feet beneath the sea bed, drilling past sediments laid down at the end of the Creataceous.
Norris said the deepest layers contain fossil remains of many animals and came from a healthy "happy-go-lucky ocean" just before the impact layers. Next youngest is a layer with small, green glass pebbles, thought to be ocean bottom material melted by the massive energy release of the impact. Then comes a rusty brown layer which Norris said is thought to be the "vaporized remains of the asteroid itself.
The heat of the impact would have been so intense, said Norris, that the stony asteroid would have instantly been reduced to vapor and thrown high into the sky, possibly ejecting some of the matter back into space. It then snowed down, like a fine powder, all over the globe. Norris said brown deposits like that in the core sample have been found elsewhere, and they have a high content of iridium, a chemical signature of asteroids.
Following the brown layer, is a two inches of gray clay with strong evidence of a nearly dead world. "It was not a completely dead ocean, but most of the species that are seen before (in earlier layers in the core sample) are gone," said Norris. "There are just some very minute fossils. These were the survivors in the ocean."
This layer represents about 5,000 years, said the scientist, and then the core samples show evidence of renewed life. "It is amazing how quickly the new species appeared," Norris said.
Although the impact occurred in the southern Gulf of Mexico, Norris went to the Atlantic Ocean, near the edge of the continental shelf. He said that the violence of the impact, followed by tsunamis (giant waves), roiled the Gulf of Mexico so much that it is unlikely to find clear core samples there. He said the theorized waves from the impact would have washed completely across Florida, depositing debris in the Atlantic.
- Anonymous4 years ago
There are quite a few theories. One very often happening one comprises a meteor hitting the section in Canada that replaced into an ice shelf on the time, changing the ambience with the dirt, etc. and melting the ice shelf. The ice shelf soften then went into the atlantic ocean and disturbed the air and water currents that save the earth cool. Then the earth have been given too warm and each little thing died off from the climate exchange. of direction, you ought to remember that this replaced into whilst the continents have been closer at the same time, so it replaced right into a various "map" then, yet it relatively is the basics.
- 1 decade ago
Dinosaurs became extinct about 65 million years ago.
A number of explanations have been suggested to explain their disappearance including food shortage or dramatic change in climate.
However, the most accepted hypothesis is that a large asteroid, probably several miles in diameter, struck the Earth hitting so hard that it actually vaporized tons of rock, soil and other things in its path. The dust and debris that was stirred blocked out much of the sunlight for possibly months or years. This, of course, killed off a lot of plants. Without plants, plant eating dinosaurs began to die off. Without plant- eating dinosaurs, meat eating dinosaurs didn't have much to eat, so they died off.
This hypothesis is supported by the fact that fossil records show that many plants died off at the same time the dinosaurs did.
Another piece of evidence in support of the hypothesis is that the element iridium, which is very rare on Earth but more common in asteroids, has been found in higher than normal amounts in rock sediments that were formed during the same period the dinosaurs became extinct.
- Anonymous1 decade ago
Nobody knows for sure, but the consensus view that it was related to a large meteorite or asteroid that struck the earth north of the Yucatan peninsula about 65 million years ago. The resulting fireball would probably not have done it, but the enormous dust cloud would have seriously affected the climate for some years, which would not have helped their food supply.
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- Anonymous1 decade ago
The latest theory has been involved with the crashing of a very large meteorite and/or asteroid into the earth's surface however there are other theories such as multiple collisions of inter-stellar materials as well as simple climate change in the eath's atmosphere. See http://en.wikipedia.org/wiki/Dinosaurs#Extinction_... for some more information regarding these theories.
- 1 decade ago
Noah couldn't fit a pair on the ark.
"Dinosaurs are used more than almost anything else to indoctrinate children and adults in the idea of millions of years of earth history. However, the Bible gives us a framework for explaining dinosaurs in terms of thousands of years of history, and solving the mystery of when they lived and what happened to them. Some key texts are Genesis 1:24–25 and Job 40:15–24.
Are dinosaurs a mystery?
Many think that the existence of dinosaurs and their demise is shrouded in such mystery that we may never know the truth about where they came from, when they lived, and what happened to them. However, dinosaurs are only a mystery if you accept the evolutionary story of their history."Source(s): http://www.answersingenesis.org/home/Area/AnswersB... (read the whole article to see why these other ridiculous theories are that of evolution, not good science) Holy Bible and Science
- 1 decade ago
a recent study makes scientists believe that a huge metorite hit the eartgh expelling dust and dirt into the air the innitial balst killed many dinosaurs the rest were killed by the ice age that followed because the sun was blocked by all of the dirt in the atmosphere
- 1 decade ago
A lot of them were eated by other dinosaurs.
Not sure how the last few died though, but I'm guessing a stegasaurus'd give anyone indigestion.
- 1 decade ago
exactly no one knows the correct answer for their death.there are many myths in relation to this.some say due to ice age,a big volcanic eruption,no food i.e, due to starvation,due to some comet/asteroid colliding with earth,due to radioactivity of elements present inside the earth.
- kateLv 41 decade ago
Who knows there are many theories, if only we could time travelSource(s): A life time of experience
- 1 decade ago
soak themselves in the muddy lake to bleach natural colors