Impact crater is a depression in the ground believed to have been caused by a meteorite, asteroid or comet crashes into a planet or a moon. In our solar system all the inner bodies have been heavily bombarded by meteoroids throughout their history. For example, this bombardment is clearly visible on the surfaces of the Moon, Mars and Mercury. However impact craters are continually erased by erosion or transformed by tectonics over time on earth.
Almost 170 terrestrial impact craters have been identified on our planet. The craters range from a few tens of meters up to about 300 km (186 miles) in diameter, and from recent times to more than two billion years in age. Only the young and relatively small impact craters are featured on this list. These craters are easier to spot. The Chicxulub crater is an example of a large and old impact crater with a diameter of 180 kilometers (110 miles). It is thought that about 65 million years ago, the impact that formed this famous crater have been responsible for the extinction of the dinosaurs.
10 Fascinating Impact Craters on Earth:
10. Kaali Crater
Somewhere between the 4th and 8th century BC, the Kaali Crater was formed from the impact of a meteorite that reached the earth. The meteorite broke into pieces at an altitude of about 5-10 km and fell to the Earth in fragments. Among the craters that formed from the impact, the largest one is about 110 meters wide and 22 meters deep. 8 smaller craters lie within a 1 kilometer radius of the main crater that was created during this bombardment.
The impact most likely burned down the entire forest of the Estonian island of Saaremaa. Many Estonian myths and stories evolved around the crater. There is a possibility that Saaremaa was the legendary Thule Island, considering the name “Thule” was connected to the Finnish word tule (“of fire”).
9. Tenoumer Crater
The Tenoumer Crater is nearly a perfect circle which is located in the Western Sahara Desert, Mauritania. The crater is 1.9 kilometers (1.2 miles) wide, and sports a rim 100 meters (330 feet) high. The cause of this crater has been long debated by the modern geologists. Some of them considered a volcano as the cause of the crater. The closer inspection of the structure revealed that the crater’s hardened “lava” was actually rock that had melted from a meteorite impact. Roughly between 10,000 and 30,000 years ago this impact occurred.
8. Lonar Crater Lake
About 50,000 years ago when a meteorite hit the surface, The Lonar Lake in Maharashtra was formed. In the resulting basaltic rock formation, a saltwater lake has evolved with a mean diameter of 1.2 kilometers (3,900 feet) and is about 137 meters (449 feet) below the crater rim. There are numerous temples that surround the lake. Except for a temple of Daityasudan, most of them are in ruins.
The temple of Daityasudan is located at the center of the Lonar town, which was built in honor of Vishnu’s victory over the giant Lonasur. The surrounding vegetation of the crater is a treat for birdwatchers and also the crater itself is a fun trek.
7. Monturaqui Crater
Located south of the Salar de Atacama in Chile, The Monturaqui Crater is approximately 460 meter (1,509 feet) in diameter by 34 meter (100 feet) deep. Even though the impact occurred about a million years ago, but the crater is still clearly visible because of the extreme arid conditions of the area.
There are many similarities between the Bonneville crater on Mars explored by the Spirit rover in 2004 and the Monturaqui crater in size and morphology. Both the Monturaqui and the Bonneville Both are shallow, the sizes of the blocks ejected near the crater rim are similar, and both of them were formed in a volcanic environment.
6. Roter Kamm Crater
The Roter Kamm crater is located in the Namib Desert, Namibia. The crater is about 2.5 km (1.6 miles) in diameter and is 130 meters (400 feet) deep. About 3.7 million years ago, it was created by a meteor with a size of a large vehicle. Even though the crater is clearly visible, but at least 100 meters (300 feet) thick sand deposits covers its floor. The crater gives the impression of a Martian surface rather than that of our own planet due to the combination with the orangey-red color of the Namib Desert.
5. Tswaing Crater
The Tswaing Crater was created about 220,000 years ago by a chondrite or stony meteorite, which is some 30 to 50 meter in diameter that hit the earth. There is a small lake in the center of the crater that is filled by a spring and rainwater. Stone tools from the Stone Age show that in order to hunt and collect salt, the crater was regularly visited by people. The local Tswana tribes call the region Tswaing which means “Place of Salt” while the European settlers named the region Zoutpan (Salt Pan).
4. Pingualuit Crater
About 1.4 million years ago, The Pingualuit Crater was created by a meteorite impact that had the force of 8500 Hiroshima-sized atomic bombs. The crater is 3.44 km (2.14 miles) in diameter, which rises 160 meters (520 feet) above the surrounding tundra and is 400 meter (1,300 feet) deep. A 270 meter (890 feet) deep lake formed at the bottom of the crater which contains some of the purest water in the world.
There are no inlets or apparent outlets of the lake, so the water accumulates from rain and snow and is only lost through evaporation. In 1943, the crater was discovered by a US Air Force plane on a meteorological flight. In the local Inuit language, Pingualuit means “where the land rises”.
3. Amguid Crater
Located in a remote area in southwestern Algeria, the Amguid Crater is a relatively young crater. The crater has formed as the result of a meteor impact about 100,000 years ago. The 30 meter (100 feet) deep meteorite impact crater is perfectly circular and it is 450 meter (1476 feet) in diameter. There are blocks of sandstones that enclose the top of the rim. These sandstones are several meters in diameter. Filled with compacted eolian silts, the center of the crater is flat.
2. Wolfe Creek Crater
300,000 years ago a meteorite with a mass of about 50,000 tons crashed into the earth and left a crater of about 875 meters (2870 feet) in diameter. This crater is named The Wolfe Creek Crater and it is located in Australia. The crater that was left by the meteorite was probably about 120 meters deep.
The wind gradually filled it with sand over the next 300,000 years and today the crater floor is 60 meters (200 feet) below the rim, which rises 25 meters above the surrounding flat desert land. Iron meteorites in small number have been found in the vicinity of the crater. In 1947, the crater was discovered during an aerial survey, even though the Aboriginal people have known about the crater for thousands of years.
1. Barringer Crater
Barringer Crater is also simply known as Meteor Crater or Arizona Crater. This crater is the best known and best preserved impact crater on Earth. Daniel Barringer was the first person to suggest that the crater was produced by a meteorite impact. As a tribute to him the crater was named the Barringer Crater and it is still privately owned by his family. The crater lies near Flagstaff, Arizona. The crater is about 1,200 meters (4,000 feet) in diameter and 170 meters (570 feet) deep, with a rim 45 meter higher on average than the surrounding plain.
About 40,000 years ago, The Barringer Crater was formed due to the impact of an iron meteorite, some 50 meters (54 yards) across and weighing several hundred thousand tons. The meteor struck at a speed of 12.8 kilometers per second (28,600 mph).
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