Confirmed impact structures on Earth
The list below includes all scientifically confirmed impact craters on Earth by February 2020: 190 impact structures. Contrary to mainstream list, this one includes Sterlitamak impact crater – it appeared in 1990, was absolutely confirmed and still is there.
Explanations to the table
- Name in fact can be different. Many impact craters can be called impact structures or astroblemes. It is important to separate the names of lakes from the names of craters because the area of the crater never is the same as the area of the lake. Thus Kaalijärv is not the same as the Kaali crater. Kaalijärv (järv is a lake in Estonian) is a lake with a diameter of 30 to 60 m, but Kaali crater has a diameter of 110 m.
- Visible craters are those, which can be deciphered as craters by looking on them in nature or in images, e.g. they are not hidden under the layer of sediments or too eroded.
- Age in most cases is a (more or less) wild guess by the rare specialists who have visited the place or very rough estimate of some scientific research. It happens that one method gives the age of e.g. 7 million years and another: 2 million years. Specialists then might agree that the age is somewhere between 7 and 2 million years (what also is a wild guess) and it finally ends with “this crater is 5.5 million years old” written in a popular science magazine. And soon after it is written in all tourists’ booklets, information signs, guidebooks, etc. Everyone seems to be happy and confident about such figures, except for scientists themselves…
- Diameter is measured between the rims (or ridges if any) of crater. Impact craters smaller than 10 m in diameter (e.g. Kunya-Urgench in Turkmenistan) are not included here. It is hard to measure a diameter of large craters (e.g. it is unclear where ends the smash in Earth’s crust), and, of course, nearly impossible to know the diameter of craters whose upper part has eroded.
- Visible depth is a maximum height difference between the highest place of the rim and deepest place in the bottom of the crater. If there is a lake, its depth is included.
- Whole depth is the same visible depth plus the thickness of sediments in the crater, which accrued after the impact. In large explosions, the bottom of the crater is covered with breccia – pieces of rocks that fell back right after the impact. This layer, in general, is not included.
- Meteorite – what type of meteorite created this crater, is it found?
- Discovery – when discovered by scientists. Sorry, the knowledge of local non-scientist folks here does not count.
- Proved – when the impact origin was proved. Sometimes it takes much time and effort.
Craters have been found on planets and moons throughout the solar system, caused when asteroids or meteors have collided with them. Our Earth has not escaped these impacts, and nearly 200 craters are known on Earth today. Some are easily visited, others are in locations few would ever want to get near. This book details all the known terrestrial impact craters, telling their age, size, and other details, as well as highlighting those easily visited.