The Chicxulub event caused the extinction of 75 percent of all species on land and sea, including the dinosaurs. But if you see something that doesn't look right, click here to contact us! Twice a week we compile our most fascinating features and deliver them straight to you. Live TV. This Day In History. History Vault. Here are five of the biggest and most significant impact craters in North America. Barringer Crater. When an impactor strikes the solid surface of a planet, a shock wave spreads out from the site of the impact.
The shock wave fractures the rock and excavates a large cavity much larger than the impactor. The impact sprays material — ejecta — out in all directions. The impactor is shattered into small pieces and may melt or vaporize. Sometimes the force of the impact is great enough to melt some of the local rock.
If an impactor is large enough, some of the material pushed toward the edges of the crater will slump back toward the center and the rock beneath the crater will rebound, or push back up, creating a central peak in the crater.
The edges of these larger craters also may slump, creating terraces that step down into the crater. What are the different kinds of craters? Simple craters are small bowl-shaped, smooth-walled craters the maximum size limit depends on the planet. This image shows a simple crater on Mars that has no central peak or terraces around its edges. The crater is 2 kilometers about 1 mile wide. An extensive blanket of ejecta covers the area around the rim. Complex craters are large craters with complicated features.
Larger craters can have terraces, central peaks, and multiple rings. Copernicus is a large crater 93 kilometers or 60 miles wide on the Moon. The inner walls of the crater have collapsed to form a series of step-like terraces, and a central peak is visible in the center of the image. A complex crater in the northern region of Mars. This crater is about 20 kilometers 12 miles across and has a large central peak and terraces around its rim.
The ejecta blanket has lobes, which may indicate wet material was ejected, suggesting that subsurface water or melted ice was mixed into the debris. Impact basins are very large impact structures that are more than kilometers miles in diameter. The largest impact basin on the Moon is kilometers miles in diameter and more than 12 kilometers 7 miles deep.
Large impact basins are also found on other planets, including Mars and Mercury. The large circular dark areas in the image are impact basins, created as huge impactors struck the Moon.
Lava later flowed across the low floors of the basins, giving them a darker, smoother appearance than the surrounding, brighter highlands. Chicxulub crater's discovery clinched what was once a wild theory: that a meteor impact wiped out the dinosaurs. A thin layer of exotic iridium metal from a meteor impact had been detected worldwide at Cretaceous mass extinction before Chicxulub was found. Now, the meteorite that carved the Chicxulub crater in Mexico's Yucatan Peninsula is widely thought to have caused or greatly contributed to the mass extinction at the end of the Cretaceous 65 million years ago, including the end of the dinosaurs.
Some scientists think Chicxulub's original crater may have been bigger than Sudbury crater in Ontario. Estimates of its original diameter range up to miles km in diameter, and its current size is 93 miles km. A rare find is buried in Russia's Popigai crater: diamonds. Some 35 million years ago, a meteorite crashed into carbon-rich graphite rock deposits in Siberia, and the impact's immense pressures and temperatures converted the carbon into diamonds.
The crater is 62 miles km wide and holds massive diamond reserves, according to the Russian government. Our first lake-filled crater, Manicouagan in Quebec is one the largest and best-preserved crater on the planet.
An example of a large and old impact crater is the Chicxulub crater with a diameter of kilometers miles. The impact that formed this famous crater is thought to have been responsible for the extinction of the dinosaurs, about 65 million years ago. It was created by a meteor with a size of a large vehicle about 3. The crater is clearly visible, but its floor is covered by sand deposits at least meters feet thick. Combined with the orangey-red color of the Namib Desert the crater gives the impression of a Martian surface rather than that of our own planet.
The Kaali Crater was created by a meteorite that reached the earth somewhere between the 4th and 8th century BC. At an altitude of about km, the meteorite broke into pieces and fell to the Earth in fragments. The largest crater is about meters wide and 22 meters deep.
Within a 1 kilometer radius of the main crater lie 8 smaller craters that were created during this bombardment. The entire forest of the Estonian island of Saaremaa most likely burned down as a result of the impact. The crater is part of many Estonian myths and stories.
Nearly a perfect circle, the Tenoumer Crater is 1. The crater is located in the western Sahara Desert, Mauritania. Modern geologists long debated what caused this crater, some of them favoring a volcano.
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