CANTON — The Yucatan area of Central America, one of the hubs of Mayan civilization, is home to a large number of sinkholes, called cenotes in the Mayan language, which served as drinking holes and bathing pools for the Maya before recorded history.
Arranged in a semi-circular belt, these holes radiate from the land to under the waters of the Caribbean. Scientists believe these sinkholes were the inner rim of a large crater caused by an asteroid hitting the earth. The impact of the crash, according to most scientists today, was the cause for the extinction of the dinosaurs. The area where the crater is located goes by the name of Chicxulub (Chic-shoe-lube), which means sign of the horns or tail of the devil in Mayan. The Maya, of course, were the ones doomsday advocates say predicted the end of the world in December of this year. And while the coincidence is interesting, any idea that the asteroid impact and the supposed Mayan doomsday prediction are related is hard to credit.
The reason? The Chicxulub impact reportedly occurred about 65 million years ago, thousands of centuries before our earliest ancestors were around, according to the evolutionary theory.
For years scientist believed the extinction of the dinosaurs was a gradual change, based on the law of natural selection and a response to slowly changing climatic conditions and/or competition from other species. A few scientists, however, believed the extinction was the result of a catastrophic event, such as a massive asteroid impact or volcanic eruption.
Evidence, however, began to swing toward the catastrophic theory. Geologists and archeologists noted a worldwide layer in the earth's crust with unusual mineralogical characteristics which could be accounted for by a collision with an asteroid. They also noted dinosaur fossils were found under but not over this layer.
But the acceptance of the impact theory led to another controversy--where was the impact site? Since most of the earth's surface is ocean, it was quite possible for the crater caused by the impact to be at the bottom of the sea, making it difficult to find. Another problem was natural erosion, which could, over millions of years, have eradicated the site. And because there are so many craters around the globe, it was difficult to pinpoint which one was the culprit or culprits, since the extinction could have been the effect of a number of impacts.
Scientists finally narrowed the site to the Chicxulub crater because of its size, the time frame in which it occurred, and other geological factors.
According to Charles Frankel in his book "The End of the Dinosaurs," the projectile which created the Chicxulub crater was roughly one thousand billion tons, hitting the earth with a force "10,000 times the explosive energy of the world's entire nuclear arsenal, American and Russian bombs combined."
Only 1 percent of the impact was transmitted to the ocean and atmosphere, which was enough to produce hurricane-force winds and a giant tsunami in the gulf. And the vacuum created by the blast caused the air to flow back into the area, creating a "two-way" hurricane effect.
While the hurricane winds caused by the impact were probably limited to the Gulf Coast and Central America, tidal waves could have been felt as far away as the Atlantic coasts of Europe and Africa. Water also raced far into the North American continent, drowning everything in its path.
The land effect was even more pronounced. The impact itself created ground waves measuring 10 on the Richter scale, 1,000 times more energy than the strongest recorded earthquakes. The impact also caused earthquakes on the other side of the world in the southwestern Pacific.
Thousands of billions of tons of rock--vaporized, molten and solid--were thrown up into the air, with a plume of thermal energy spreading in all directions, fueled by the near vacuum caused by the asteroid's plunge through the atmosphere. The upper layers of the atmosphere became a blazing inferno, and the amount of heat reaching the earth would have caused soil temperatures to rise to the heat level of an oven set on broil. Fires would have been ignited all over the world, burning animals and plants to a crisp. As Frankel put it, "one might even wonder why there were any survivors at all."
Scientists have projected this was followed by a dust cloud covering the earth for an estimated two years, with total darkness for months and a disruption of the process of photosynthesis, causing problems for the plants which are the basis of the food chain. Temperatures plummeted and then a warming trend caused by the greenhouse effect of the released gasses enveloped the earth for thousands, perhaps tens of thousands of years.
Since ocean plankton and terrestrial plants were seriously affected, the animals who used them for food were also impacted. And the chain of extinction continued as the reduction of herbivores lead to starvation for many carnivores.
Species which survived did so, in part, because of smaller size. Since it takes less food to sustain smaller animals than larger ones, less available food would have a more direct impact on larger animals such as dinosaurs. Another factor was what Frankel termed the "bunker effect," with amphibians and sea-bottom species protected by diving to the bottom of the oceans and lakes, and mammals burrowing into the earth for protection. Most important, however, could have been the fact that surviving species were more diversified in their sources of food, while those which went extinct were more specialized.
And while the effects of the Chicxulub impact caused what scientists refer to as quick extinction, the end of the dinosaurs did not happen overnight. The dinosaur extinction took place over thousands of years, a long time for us but a mere blip in geological time.
But the death of the dinosaurs was not the first extinction in earth's history, or even the most lethal. Next, we turn our attention to those earlier mass extinctions. The Yucatan area of Central America, one of the hubs of Mayan civilization, is home to a large number of sinkholes, called cenotes in the Mayan language, which served as drinking holes and bathing pools for the Maya before recorded history.
Arranged in a semi-circular belt, these holes radiate from the land to under the waters of the Caribbean. Scientists believe these sinkholes were the inner rim of a large crater caused by an asteroid hitting the earth. The impact of the crash, according to most scientists today, was the cause for the extinction of the dinosaurs. The area where the crater is located goes by the name of Chicxulub (Chic-shoe-lube), which means sign of the horns or tail of the devil in Mayan. The Maya, of course, were the ones doomsday advocates say predicted the end of the world in December of this year. And while the coincidence is interesting, any idea that the asteroid impact and the supposed Mayan doomsday prediction are related is hard to credit. The reason? The Chicxulub impact reportedly occurred about 65 million years ago, thousands
of centuries before our earliest ancestors were around, according to the evolutionary theory. For years scientist believed the extinction of the dinosaurs was a gradual change, based on the law of natural selection and a response to slowly changing climatic conditions and/or competition from other species. A few scientists, however, believed the extinction was the result of a catastrophic event, such as a massive asteroid impact or volcanic eruption.
Evidence, however, began to swing toward the catastrophic theory. Geologists and archeologists noted a worldwide layer in the earth's crust with unusual mineralogical characteristics which could be accounted for by a collision with an asteroid. They also noted dinosaur fossils were found under but not over this layer.
But the acceptance of the impact theory led to another controversy--where was the impact site? Since most of the earth's surface is ocean, it was quite possible for the crater caused by the impact to be at the bottom of the sea, making it difficult to find. Another problem was natural erosion, which could, over millions of years, have eradicated the site. And because there are so many craters around the globe, it was difficult to pinpoint which one was the culprit or culprits, since the extinction could have been the effect of a number of impacts. Scientists finally narrowed the site to the Chicxulub crater because of its size, the time frame in which it occurred, and other geological factors.
According to Charles Frankel in his book "The End of the Dinosaurs," the projectile which created the Chicxulub crater was roughly one thousand billion tons, hitting the earth with a force "10,000 times the explosive energy of the world's entire nuclear arsenal, American and Russian bombs combined."
Only 1 percent of the impact was transmitted to the ocean and atmosphere, which was enough to produce hurricane-force winds and a giant tsunami in the gulf. And the vacuum created by the blast caused the air to flow back into the area, creating a "two-way" hurricane effect.
While the hurricane winds caused by the impact were probably limited to the Gulf Coast and Central America, tidal waves could have been felt as far away as the Atlantic coasts of Europe and Africa. Water also raced far into the North American continent, drowning everything in its path.
The land effect was even more pronounced. The impact itself created ground waves measuring 10 on the Richter scale, 1,000 times more energy than the strongest recorded earthquakes. The impact also caused earthquakes on the other side of the world in the southwestern Pacific.
Thousands of billions of tons of rock--vaporized, molten and solid--were thrown up into the air, with a plume of thermal energy spreading in all directions, fueled by the near vacuum caused by the asteroid's plunge through the atmosphere. The upper layers of the atmosphere became a blazing inferno, and the amount of heat reaching the earth would have caused soil temperatures to rise to the heat level of an oven set on broil. Fires would have been ignited all over the world, burning animals and plants to a crisp. As Frankel put it, "one might even wonder why there were any survivors at all."
Scientists have projected this was followed by a dust cloud covering the earth for an estimated two years, with total darkness for months and a disruption of the process of photosynthesis, causing problems for the plants which are the basis of the food chain. Temperatures plummeted and then a warming trend caused by the greenhouse effect of the released gasses enveloped the earth for thousands, perhaps tens of thousands of years.
Since ocean plankton and terrestrial plants were seriously affected, the animals who used them for food were also impacted. And the chain of extinction continued as the reduction of herbivores lead to starvation for many carnivores.
Species which survived did so, in part, because of smaller size. Since it takes less food to sustain smaller animals than larger ones, less available food would have a more direct impact on larger animals such as dinosaurs. Another factor was what Frankel termed the "bunker effect," with amphibians and sea-bottom species protected by diving to the bottom of the oceans and lakes, and mammals burrowing into the earth for protection. Most important, however, could have been the fact that surviving species were more diversified in their sources of food, while those which went extinct were more specialized.
And while the effects of the Chicxulub impact caused what scientists refer to as quick extinction, the end of the dinosaurs did not happen overnight. The dinosaur extinction took place over thousands of years, a long time for us but a mere blip in geological time.
But the death of the dinosaurs was not the first extinction in earth's history, or even the most lethal. Next, we turn our attention to those earlier mass extinctions.
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