Cenozoic Mesozoic Paleozoic Precambrian This list of impact structures in Africa includes all 20 confirmed impact craters as listed in the Earth Impact Database. These features were caused by the collision of large meteorites or comets with the Earth. For eroded or buried craters, the stated diameter typically refers to an estimate of original rim diameter, and may not correspond to present surface features.
The following craters are officially considered "unconfirmed" because they are not listed in the Earth Impact Database. Due to stringent requirements regarding evidence and peer-reviewed publication, newly discovered craters or those with difficulty collecting evidence generally are known for some time before becoming listed. However, entries on the unconfirmed list could still have an impact origin disproven.
| Name | Location | Diameter | Age | Coordinates |
|---|---|---|---|---|
| Kebira | Gilf Kebir region, Egypt | 31 km | 100 million | 24°40′N24°58′E / 24.667°N 24.967°E |
| Temimichat [2] | Mauritania | 0.75 km | unknown | 24°15′N9°39′W / 24.250°N 9.650°W |
| Wembo-Nyama ring structure [3] [4] | DR Congo | 36–46 km (est.) | 60 million | 3°37′52″S24°31′07″E / 3.63111°S 24.51861°E |
| Mahas 1 [5] | Northern, Sudan | 2.85 km | Unknown | 20°01′53″N30°13′48″E / 20.03139°N 30.23000°E |
| Circular feature with clear ca. rim 300 m above ground level centred around the hamlet of Baw | Blue Nile State | 5 km | Unknown | 11°20′00″N30°03′00″E / 11.33333°N 30.05000°E |
| Circular Feature [6] | North-Central Niger | 10 km | Unknown | 21°21′14.56″N 9° 8′32.24″E |
| Vélingara circular structure [7] | Kolda Region, Senegal | 48 km | Unknown | 13°00′00″N14°08′00″W / 13.00000°N 14.13333°W |
1 Mahas was anonymously added Jan 2015, but the coordinates do show a convincing impact-like structure.
It appears to me there is also an impact crater several miles in diameter, approximately 40-45 miles to the SE of Tete, Mozambique. But this only based from an aerial inspection from Google Earth and not from any ground inspection or geological verification.
An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Lunar impact craters range from microscopic craters on lunar rocks returned by the Apollo program and small, simple, bowl-shaped depressions in the lunar regolith to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth.
An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effect. When large objects impact terrestrial planets such as the Earth, there can be significant physical and biospheric consequences, as the impacting body is usually traveling at several kilometres a second, though atmospheres mitigate many surface impacts through atmospheric entry. Impact craters and structures are dominant landforms on many of the Solar System's solid objects and present the strongest empirical evidence for their frequency and scale.
Aorounga is an eroded meteorite impact crater in Chad, Africa. The exposed remnant of the crater is 12.6 km (7.8 mi) in diameter and its age is estimated to be less than 345 million years.
Riachão Ring is a meteorite impact crater in Brazil. It lies within the Parnaíba Basin. It is 4.5 kilometres (2.8 mi) in diameter and the age is estimated to be less than 200 million years. The crater is exposed at the surface.
Rochechouart impact structure or Rochechouart astrobleme is an impact structure in France. Erosion has over the millions of years mostly destroyed its impact crater, the initial surface expression of the asteroid impact leaving highly deformed bedrock and fragments of the crater's floor as evidence of it.
The Vredefort impact structure is one of the largest verified impact structures on Earth. The crater, which has since been eroded away, has been estimated at 170–300 kilometres (110–190 mi) across when it was formed. The remaining structure, comprising the deformed underlying bedrock, is located in present-day Free State province of South Africa. It is named after the town of Vredefort, which is near its centre. The structure's central uplift is known as the Vredefort Dome. The impact structure was formed during the Paleoproterozoic Era, 2,023 million years ago. It is the second-oldest known impact structure on Earth, after Yarrabubba.
Kebira Crater is the name given to a circular topographic feature that was identified in 2007 by Farouk El-Baz and Eman Ghoneim using satellite imagery, Radarsat-1, and Shuttle Radar Topography Mission (SRTM) data in the Sahara desert. This feature straddles the border between Egypt and Libya. The name of this feature is derived from the Arabic word for "large", and also from its location near the Gilf Kebir region in southwest Egypt. Based solely on their interpretations of the remote sensing data, they argue that this feature is an exceptionally large, double-ringed, extraterrestrial impact crater. They suggest that the crater's original appearance has been obscured by wind and water erosion over time. Finally, they speculated that this feature might be the source of the yellow-green silica glass fragments, known as "Libyan desert glass", that can be found across part of Egypt's Libyan Desert. They neither conducted any fieldwork at this feature nor studied any samples collected from it. However, the Kebira Crater is currently not listed in the Earth Impact Database. Field trips to investigate the feature have found no supporting evidence. The "central uplift" clearly retains the horizontal bedding of the surrounding sandstone tableland, providing clear evidence against a possible impact origin.
An impact structure is a generally circular or craterlike geologic structure of deformed bedrock or sediment produced by impact on a planetary surface, whatever the stage of erosion of the structure. In contrast, an impact crater is the surface expression of an impact structure. In many cases, on Earth, the impact crater has been destroyed by erosion, leaving only the deformed rock or sediment of the impact structure behind. This is the fate of almost all old impact craters on Earth, unlike the ancient pristine craters preserved on the Moon and other geologically inactive rocky bodies with old surfaces in the Solar System. Impact structure is synonymous with the less commonly used term astrobleme meaning "star wound".
Ramgarh crater, also known as Ramgarh structure, Ramgarh Dome and Ramgarh astrobleme, is a meteor impact crater of 3.5 kilometres (2.2 mi) diameter in Kota plateau of Vindhya range located adjacent to Ramgarh village in Mangrol tehsil of Baran district in Rajasthan state of India. When formally accepted as the third crater in India, its diameter size would be between the two already confirmed craters in India - Dhala in Madhya Pradesh with 14 km diameter and Lonar in Buldhana district of Maharashtra with 1.8 km diameter.
Complex craters are a type of large impact crater morphology.
Traces of Catastrophe: A Handbook of Shock-Metamorphic Effects in Terrestrial Meteorite Impact Structures is a book written by Bevan M. French of the Smithsonian Institution. It is a comprehensive technical reference on the science of impact craters. It was published in 1998 by the Lunar and Planetary Institute (LPI), which is part of the Universities Space Research Association (USRA). It was originally available in hard copy from LPI, but is now only available as a portable document format (PDF) e-book free download.
As of June 2018, 12 confirmed impact craters have been found in Finland. They are listed below, sorted by original diameter.
