Discovered in 1994, it is not exposed at the surface, but has been mapped by magnetic and gravimetric surveys. The average observed impact crater is ≈20 km in diameter which corresponds to an energy release of ≈5.5 × 10 5 mT (Toon et al. Other important craters in Southern Africa are Roter Kamm, Kalkkop, Morokweng … The entire circular crater is about 53 mi (85 km) in diameter and 0.81 mi (1.3 km) deep, an area twice the size of Rhode Island, and nearly as deep as the Grand Canyon. 3. ... That is the estimated size of the meteorite which formed the Vredefort Crater. The crater is a multiple-ring structure about 100 km (60 mi) across. Specs: This impact crater formed what is now Lake Manicouagan. September, 2017. Rather than the simple bowl shape we often associate with craters, Acraman has a complicated surface with variations in elevation. As well as ice, oceans and ice ages. It’s incredible that so much of the meteorite survived intact, especially when the formation of an impact crater only a fraction of the size of Morokweng can generate temperatures up to 14,000 degrees Celsius (25,000 °F). The kind of crater will depend on the size, composition, degree of fragmentation, and incoming angle of the impactor. Lunar and Planetary Institute, Large Meteorite Impacts and Planetary Evolution IV Conference, Parys 18-22 August 2008, Abstract (to poster) #3048. The beachball-sized fossil meteorite was drilled out of South Africa's 145-million-year-old (± 0.8) Morokweng crater. Download Full PDF Package. A second crater, similar in size to the main crater, appears as a circular trough in the center of the image. [10] The date of Morokweng is also interesting, as it is said to have been created around 145 million years ago. Ewing is a possible oceanic crater. Chicxulub crater on the northern coast of the Yucatán Peninsula in Mexico, in a computer-generated image synthesized from gravity and magnetic-field data. It was formed around 145 million years ago. Most recently, detailed modeling of the gravity and magnetic anomalies over the Morokweng region resulted in further support for a maximum crater diameter of 70–80 km. Recently, however, solid unmolten fragments of asteroidal material, up to 25 cm in size, were recovered from within the large (≥80 km) Morokweng crater, South Africa (Maier et al. This is the Morokweng Crater in the Kalahari Desert. A 220Km crater Manicougan, Quebec at the end of the Triassic (206myr) marked the end of the massive lycopod and glossopterid forests that produced today's coal. You’re welcome. Because we have an atmosphere, weather and erosion and above all a lot of time. Cosmologists have speculated that black holes the size of a proton could have formed during the early days of the Big Bang when the universe began. The Morokweng crater, centered at 26o32' S and 23o32' E, is at the edge of the Kalahari Desert in northern South Africa. READ PAPER. The crater is a multiple-ring structure about 100 kilometers (60 miles) across, with its 70 kilometer (40 mile) diameter inner ring as its most prominent feature; it contains a 70 kilometer (40 mile) diameter annular lake, the Manicouagan Reservoir, surrounding an inner island plateau, René-Levasseur Island. Source: wikimedia.org. geological materials, micrometer-size nuggets of PGE can ac-Fig. Woodleigh is now in the NRC database and Bedout is looking promising. Kara Crater Asteroid impact date: Estimated 70.3 million years ago Location: Nenetsia, Russia By applying our results to the Morokweng crater‐forming impact, we suggest that the high (unmolten) meteoritic content of Morokweng crater can be explained by a low (approximately 11.2 km s −1 ) velocity, low porosity (0–10%), prolate‐shaped impactor, impacting at a high angle (≥45 o ). The buried crater, over 90 miles in diameter, was created when a massive asteroid struck the planet 66 million years ago and brought a calamitous end to the reign of dinosaurs. 6. [2] It is about 1,200 m (4,000 ft) in diameter, some 170 m deep (570 ft), and is surrounded by a rim that rises 45 m (150 ft) above the surrounding plains. Sample of the Morokweng Asteroid, 2006. 40Ar/ 39Ar thermochronology of the fossil LL6-chondrite from the Morokweng crater, South Africa. Fill in the data for the fourth column in the table below Name Location Crater from ASTRONOMY 101 at Front Range Community College as in Figure 2a, using data from the Morokweng impact structure, South Africa), the trend follows a mixing line between the composition of the average target rocks (a few parts per billion at Morokweng) and the impactor (whose composition is considered to be similar to that of a chon-drite clast found in the Morokweng melt rock (Fig. "Previous research estimated the size of the impact crater between 60 km (37 mi) and more than 120 km (75 mi) in diameter," says Morgan Cox, an author of the study. Reports on its diameter vary from 25 to 75 miles (40 to 120 kilometers). Puchezh-Katunki – an 80 km crater over in the Nizhny Novgorod Oblast in Russia 9. The Barringer Crater is one of the best-preserved on the planet, but it is only about 50,000 years old. In spite of the uncertainties, these morphometric parameters rank Morokweng Morokweng is another huge and ancient crater in South Africa, this time on the edge of the Kalahari Desert. Whatever the case may be, impacts the size of Chicxulub occur on Earth about once every 100 million years, making the crater in Mexico a humbling and perhaps unsettling reminder of life’s fragility. Kara crater Kara crater is a 70.3-million-year-old eroded crater exposed in Russia´s Yugorsky Peninsula. 2 – Excavation The crater excavation stage (Melosh, 1980) overlaps somewhat with the compression stage and involves two processes: Asteroid impact date: Estimated 145 million years ago. The Manicouagan crater is one of the oldest known impact craters.It is in the Côte-Nord region of Québec, Canada.. 1997) and is ≈10 000 times more powerful than the largest hydrogen bomb ever exploded. [10] Harry sent the signal to launch and looked at his hardened smartphone to see it start the countdown timer to the preparatory bombardment. Morokweng Crater, North West, South Africa, 145 million years ago – 43 miles. Together, the lake and the roughly 2,000 km2 island are known as the “eye of Québec.”. Crater diameter estimates can ... and discussed that a crater-size cutoff of 30 km would eliminate most secondary craters caused by ejecta from large impacts. Morokweng Crater. Specs: Located near the Kalahari Desert in South Africa, this crater contained the fossilized remains of the meteorite that created it. They also portray the structure of the glacier ice that flows into and fills the crater. Manicouagan Crater. This can affect the order of size: for example, Sudbury's maximum damage diameter is ~260 km (as defined by the outermost ring diameter), while that of Chicxulub is ~240 km. Top 10 largest asteroid impacts by crater size. Fred Jourdan. The crater is 215 million years old, and exhibits an 85 km diameter (image credit: NASA). Meteor Crater lies at an elevation of about 1,740 m (5,709 ft) above sea level. What surprised them the most is that when they drilled to look for rock samples to verify the impact, the remnants of the crater were still present 770 m below the surface, even after 145 million year ago (approximately the Jurassic – Cretaceous era). Sometimes a meteorite is a large one, travelling very fast, and with a large amount of energy. Only rather recently did scientists begin to widely acknowledge … Alphabetical lists for different continents can be found under Craters by continent below. oumou sangaré yere faga oumou sangaré yere faga. These fragment finds suggest that impactor material can survive large‐scale impacts without melting and remain within the crater. 31/mai/2013 - Breaking science news and articles on global warming, extrasolar planets, astronomy, biology, nanotechnology, and all things science. Rock physical properties to guide the modeling were measured on samples from three drill cores in the central part of the structure. Location: Virginia, USA. The Morokweng impact structure is similarly surrounded by rocks of the Kraaipan greenstone formation which are potential source of Ni and PGEs. These values were obtained assuming a shock meta-are consistent with the exceptional volume of the melt sheet [1, 2, 6]. 6. Estimates of its actual diameter range from 106 to a whopping 186 miles (170 to 300 kilometers), which, if … [13]) A bolide: a very bright meteor of an apparent magnitude of −14 or brighter. The Morokweng crater The crater, formed by an asteroid 5-10 km (3-6 miles) in diameter, is at least about 160 km (100 miles)in diameter and the age is estimated to be 145.0 ± 0.8 million years, placing it on the Jurassic-Cretaceous boundary. Morokweng's unusual gravitational and magnetic profile has allowed scientists to map the crater, and mining drills have probed the twisted rock at the base of the crater that was melted by the impact. The Morokweng crater is an impact crater, about 160 km (100 mi) in diameter, that lies buried under the sands of the Kalahari Desert near Morokweng, in the northwest part of South Africa (latitude 26° 28' S, longitude 23° 32' E). If confirmed, its diameter size would be between the two confirmed Indian craters, 14 kilometres (8.7 mi) Dhala and 1.8 kilometres (1.1 mi) Lonar. See PASSC (updated URL) for a full list of craters. Current estimates put it at around 70 km, making it one of the more substantial impact events in the planet’s history. ... How old is the Morokweng crater? Whatever the case may be, impacts the size of Chicxulub occur on Earth about once every 100 million years, making the crater in Mexico a humbling and perhaps unsettling reminder of life’s fragility. Specs: This crater is not exposed at the surface and has led to many discrepancies regarding its actual size. 667. The number of impact crater is 169 and it estimate to 5000 undiscovered craters. Morokweng Impact Structure and Morokweng Fossil Meteorite: The Morokweng impact crater in South Africa is a complex, multiring structure with a ~130 km radius external ring and asymmetric radial sectors [3]. 2a). Zircons recovered from the quartz norite, yield U-Pb ages of 145 ± 0.8 Ma, and biotites provide Ar-Ar ages of 144 ± 4 Ma. Download coordinates as: KML. 16 octobre 2020 Commentaires 0 Commentaire Commentaires 0 Commentaire The crater is not exposed at the surface and therefore its size is uncertain. Lunar and interplanetary spaceflight over the past 50 years has provided us with detailed maps of the old, impact-crater covered surfaces of our Solar System neighbors. BIG ROCK Traveling at speeds of over 26,000 mph, this 150 foot wide meteorite weighed 300,000 tons and formed the 550 foot deep, mile wide impact crater. Amelia Creek crater is an impact structure (or astrobleme), the eroded remnant of a former impact crater, located in the Davenport Range, Northern Territory, Australia. The Morokweng crater in South Africa dates to roughly the same time period, although at 70km in diameter was a much larger impact than that which created Gosses Bluff. About 86% of the meteorites that fall on Earth are chondrites, which are named for the small, round particles they contain. In the Earth Impact Database, we are striving to cite the collapsed transient crater value where possible. 679. Here we review borehole and geophysical data from which we derive a 240-km-crater diameter. Previous size estimates for the Morokweng impact structure ranged between 70 and 340 km, and those Year-round open season. Morokweng impact structure, South Africa: Geologic, petrographic, and isotopic results, and implications for the size of the structure Author(s) Wolf Uwe Reimold Wolf Uwe Reimold Search for other works by this author on: GSW. Only in the 1940’s aerial photographs revealed that it is a perfectly circular white deposit, approximately 640m in diameter, so it was thought to be a crater of volcanic origin. View Product Details. The ( The land collided with a huge meteorite, after which a huge crater of more than 65 km in diameter was formed. 240 km for this crater. Kara Crater, Russia. 7, 8, 9, … Description. Asteroid impact date: Estimated 215 million years ago. Russian asteroid explosion and past impactors paint a potentially grim future for Earth. A large fragment of the impacting meteorite was found beneath the melt sheet at the ≥70 km Morokweng impact structure, South Africa (Schmieder 2010). The sinkhole was formed when underground water dissolved the dolomite rocks above. This vertical, submerged […] Still other sources place Chicxulub at … UNSPECIFIED - MAY 23: Sample of a large fragment of an asteroid that punched a 160km-wide hole in the Earth's surface in the Kalahari Desert, South Africa. The original discovery team stated in 2000 that it may be up to 120 km (75 mi) in diameter, but others argue it may be much smaller, with one 2003 study suggesting a diameter closer to 60 km (37 mi). This produces an impact that is powerful enough to vaporize rock, excavate a huge crater and blast millions of tons of ejecta into the air. Grazing meteoroids could ignite continentalscale fires. The crater is said to have been formed by a 3km (1.8mi) diameter asteroid, and caused a crater … The exact size of the Morokweng Crater is difficult to determine as it is wholly covered by newer rocks and sand. The most recent major impact formed the Chesapeake Bay Crater about 35 million years ago, in Virginia. The Morokweng crater (or Morokweng impact structure) is an impact structure buried beneath the Kalahari Desert near the town of Morokweng in South Africa's North West province, close to the border with Botswana. 6. Come see and feel the surface of this incredible piece of history! Our study confirms that this structure has a minimum diameter of 215 km at present, and represents one of the largest terrestrial impact craters. The Morokweng crater in South Africa dates to roughly the same time period, although at 70km in diameter was a much larger impact than that which created Gosses Bluff. The Morokweng impact crater coincides with the Jurassic-Cretaceous boundary and hosts boulder-size pristine LL chondrite clasts in its >=870 m melt sheet. Crater sizes Name Age Dia. Discovered in the 1990s, the crater is estimated to be around 145 million years old and is about 70 kilometers (45 mi) wide. These fragment finds suggest that impactor material can survive large-scale impacts without melting and remain within the crater. A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science. (for timing, Melosh and Ivanov, 1999; Kenkmann, 2002) The third stage of crater formation, collapse, is a much slower process. Today this Crater is 43 miles in diameter along with its size. - 15593985 https://interestingengineering.com/11-of-earths-largest-impact-craters … Chesapeake Bay Crater, Virginia, United States, 35 million years ago – 53 miles. The large ≥70 km diameter Morokweng crater in South Africa has been dated at 145 ± 0.8 Myr ago, close to the accepted time of the Jurassic/Cretaceous boundary (145 Myr ago; Hart et al., 1997, Reimold et al., 2002 ). Abstract The geophysical characteristics of the 145-Ma-old Morokweng impact structure in South Africa have been studied by modeling combined gravity and magnetic data along a 100-km cross section. 9.Morokweng crater This is a crater that lies beneath the Kalahari Desert, in South Africa, close to Botswana.It is a 70 km large crater which was formed 145 million years ago, on the Jurassic-Cretacic boundary. But this crater was caused by an asteroid and not a meteor, hence it is not a site that attracts tourists or enthusiasts who wish to celebrate Meteor Watch Day. File:Beachy Head and Lighthouse, East Sussex, England - April 2010 crop horizon corrected.jpg geophysics and sedimentology to estimate the original size of the Acraman crater and infer the dynamics and likely environmental effects of the impact event. The Morokweng crater lies beneath a 150-to-200-meter-thick layer of sand in the Kalahari Desert. Download PDF. [2] The crater is said to have been formed by a 3km (1.8mi) diameter asteroid, and caused a crater at least 70km (43.8mi) in diameter. What surprised them the most is that when they drilled to look for rock samples to verify the impact, the remnants of the crater were still present 770 m below the surface, even after 145 million year ago (approximately the Jurassic – Cretaceous era). (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng Crater in South Africa, was reported in May, 2006.) This structure is the result of the large-scale cosmic catastrophe that occurred about 70 million years ago. But this crater was caused by an asteroid and not a meteor, hence it is not a site that attracts tourists or enthusiasts who wish to celebrate Meteor Watch Day. The Morokweng crater in South Africa dates to roughly the same time period, although at 70km in diameter was a much larger impact than that which created Gosses Bluff. The Canon Diablo ('Devil's Canyon') crater in Arizona, USA, has a 1.5 km diameter and is 170 m deep. Figure 1 jFormation of Copernicus crater by a low-speed impact. Morokweng, South Africa: A large impact structure of Jurassic-Cretaceous boundary age Christian Koeberl* Institute of Geochemistry, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria Richard A.Armstrong Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia Wolf Uwe Reimold This paper. The Kara crater is situated in Russia, Nenetsia. What happened was that this … (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng crater in South Africa, was reported in May 2006. However, numerical modeling techniques by Collins et al. Location: Quebec, Canada Based on the size of the crater, the team estimates that the asteroid would have been around 0.75 miles across and would have weighed 11 to 12 billion tons as it … Style: CT1983-105. Researchers think the 40-mile-wide (65 km) crater was once more than 75 miles (120 km) in diameter. Size: 53 miles wide. Harry observed the battle field, Morokweng impact crater, they liked to use these craters for some reason, despite the tactical disadvantage it left them. These data provide strong evidence for the occurrence of a Late Jurassic impact crater (the Morokweng impact structure) ∼ 100 m beneath the surface. Scientists detected the ancient sear a decade ago after noting anomalies in the planet's magnetic and gravitational fields in that region, says Rodger J. Hart, a geochemist at University of the Witwatersrand in Johannesburg. According to McDonald et al., (2001) the only terrestrial (relating to Earth) melt rocks with similar PGE characteristics as the Morokweng impact structure is the Fe-Ni-Cu The Morokweng impact structure in South Africa was formed 145 Ma ago, at the time of the minor mass extinction that marks the Jurassic-Cretaceous boundary. The crater is hundreds of millions of years old and so is greatly eroded. The Morokweng impact crater, South Africa: a complex, multiring structure with a ~130 radius external ring and asymmetric radial sectors. Located in the Kalahari Desert in North West province, the Morokweng C rater was formed around 145-million years ago and is estimated to be 70km in diameter. b, 700s after impact, the impactor material (red) is concentrated in the central peak of the crater. The percent species extinctions show a significant linear relationship with final crater … To keep the lists manageable, only the largest craters within a time period are included. One of the best-known impact craters is the Vredefort crater It was 160–300 km across when it was formed approximately ± 4 million years during the Paleoproterozoic Era. (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng crater in South Africa, was reported in May 2006. On Earth, impacts of certain size even affected the evolution of life. Introduction: The Morokweng impact crater situ-ated in the North West Province of South Africa was formed ~145±2 Ma ago by an impact of LL-6 chon-drite [1-5]. Falling rocks and dust are superpositioned over other layers, particles are sorted, unstable slopes shift and fall, and the centers of complex structures rebound, sometimes hundreds of meters from their compressed position. These results are supported by the fact that the ages of the four known ≥ 100-km diameter craters of the last 260 My (Popigai, Chicxulub, Morokweng, and Manicouagan) are all correlative with times of documented extinction episodes, whereas smaller craters are not. Asteroid impact date: Estimated 145 million years ago It is the Morokweng Crater in the Kalahari Desert. 6) Morokweng crater: This was formed in the Kalahari desert near the town of morokweng in South Africa. The crater contains an annular lake (a circular lake caused by the impact of a meteor) called Manicouagan Reservoir which surrounds René-Levasseur Island. It is believed that the Manicouagan Crater, with an initial diameter of 100 kilometers, was created by the impact of an asteroid 5 kilometers in diameter. GET HANDS ON The Holsinger Meteorite, weighing 1,406 lbs., is the largest ever found at Meteor Crater. (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng crater in South Africa, was reported in May 2006. The Morokweng crater (or Morokweng impact structure) is an impact crater buried beneath the Kalahari Desert near the town of Morokweng in the Northwest Province of South Africa, close to the border with Botswana. (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng crater in South Africa, was reported in May 2006.) A large fragment has been found of an asteroid that punched a 160km-wide hole in the Earth's surface. The Crater Foam midsole is made from a spacey mix of foam materials and 10% Nike Grind rubber, while the speckled Waffle outsole is made from 15% Nike Grind rubber, making each pair unique and durable. Strangways is a large impact structure, the eroded remnant of a former impact crater, situated in the Northern Territory of Australia. Morokweng – South Africa’s other entry is a 70 km crater, which, with Vredfordt, is really just proof that God doesn’t like South Africa. This false-color satellite image of Manicouagan Crater was captured by Sentinel-1A on March 21, 2015. Popigai Crater impact: Large asteroids can hit the Earth at a velocity of 15 to 20 miles per second. 5) Manicouagen crater: This was formed in Quebec, Canada. As well as by mountain orogeny processes. One of the best-known impact craters is the Vredefort crater It was 160–300 km across when it was formed approximately ± 4 million years during the Paleoproterozoic Era. Interpreted geology of the Morokweng impact structure, with location of selected boreholes. Location: North West, South Africa. It was caused by the impact of a 5 km (3 mi) diameter asteroid about 215.5 million years ago, in the Upper Triassic.. The Morokweng crater (or Morokweng impact structure) is an impact crater buried beneath the Kalahari Desert near the town of Morokweng in the Northwest Province of South Africa, close to the border with Botswana. The size of craters invariably changes over time; in the short term, craters shrink as a result of slumping, and over the longer term erosion and other geological processes quickly hide impact craters on the Earth. Morokweng Crater. The remains of the meteorite that created this crater were still in its depth. Finally, the eccentric position of the well-studied Morokweng impact melt sheet [1, 2, 3. The Morokweng crater is an impact crater buried beneath the Kalahari Desert near the town of Morokweng in South Africa's North West province, close to the border with Botswana. Micropholis was one of the first dissorophoids to be named by English paleontologist Thomas Huxley in 1859 based on a partial skull. Morokweng formed 145 million years ago and is 44 miles (70 km) wide. THAT'S A. Beaverhead crater In 1947 a mining company drilled a borehole on Kalkkop that revealed it contains remarkably pure limestone down to a … Many gold mines were found on the site of the crater, which alone accounts for half of the world production of gold. The crater was likely around 190 miles in diameter when it was first formed. Geographical location and satellite image of the 100-km Popigai impact structure. It was buried underneath South Africa’s Kalahari Desert. central uplift with a diameter of ~ 80 km, and a crater final rim of ~190±10 km. The original discovery team believe it may be up to 120 km (75 mi) in diameter, [1] but others argue it may be much smaller, with one study suggesting a diameter closer to 60 km (37 mi). 8. Geological studies have found that, over time, Acraman’s surface eroded several kilometers below the original crater floor. 5. Age: 35 million years. What is the valve that controls the entrance to the stomach and prevents backflow to the esophagus? Micropholis stowii (properly Micropholis stowi), the type species, is named for George William Stow, the South African geologist and ethnologist who discovered the specimen and who proposed that it represented some extinct amphibian. The boulder size ($25 cm) in the impact melt of the Morokweng crater variation of the Cr isotopic composition is a result of the decay of in South Africa. It has a diameter of at least 70 kilometers and … indicate that the post-impact diameter was likely to have been around 25 mi (40 km), rather than the observed 53 mi (85 km). The buried crater, over 90 miles in diameter, was created when a massive asteroid struck the planet 66 million years ago and brought a calamitous end to the reign of dinosaurs. The Morokweng impact structure in South Africa was formed 145 Ma ago, at the time of the minor mass extinction that marks the Jurassic-Cretaceous boundary. Boesmansgat is a natural sinkhole on the farm Mount Carmel, located some 55 km South of Kuruman on the Danielskuil road. Morokweng crater, or Morkweng impact structure, is a large meteor impact crater found buried beneath the Kalahari Desert, near the town of Morokweng in South Africa. In the past scientists believed that any meteorite like this one (more than 4 km accross) would have melted or vaporized upon impact leaving no remains. The 144 Ma Morokweng Impact Structure, South Africa: Evidence for a ~240 km Crater, Lunar and Planetary Science XXXIX, abstract #1236. An impact of this size would be expected to cause regional catastrophic damage. It has been weathered away so … More than a dozen known impactors created 50 km sized craters (and larger) on … We were impacted plenty of times but the scars are removed by erosion and time. (The very first example of a stony meteorite found in association with a large impact crater, the Morokweng crater in South Africa, was reported in May 2006. Morokweng Crater Asteroid impact date: Estimated 145 million years ago Location: North West, South Africa Specs: Located near the Kalahari Desert in South Africa, this crater contained the fossilized remains of the meteorite that created it. The force at the point of impact exceeds the temperature and pressure required to produce diamonds. It was buried underneath South Africa’s Kalahari Desert. Ramgarh crater, 3.5 kilometres (2.2 mi) in diameter, is a potential meteor crater in Kota plateau of Vindhya range located near Ramgarh village, Mangrol tehsil of Baran district in Rajasthan state of India. The crater is not exposed at the surface and therefore its size is uncertain. It is a unique discovery because large objects are widely believed to completely melt or vaporise as they collide with the planet. (km) Chicxulub 64.98 Myr 170 Morokweng 145 70 Vredefort 2023 300 This source estimates Morokweng at 100 km smaller than Chicxulub. This produces an impact that is powerful enough to vaporize rock, excavate a huge crater and blast millions of tons of ejecta into the air. "Eltanin" was an ocean impact and did not leave a crater.Bedout and Woodleigh are speculative - see below. A short summary of this paper. The crater, formed by an asteroid 5 to 10 km (3.1 to 6.2 mi) in diameter, is at least about 70 km (43 mi) in diameter and the age is estimated to be 145.0 ± 0.8 million years, placing it at the Jurassic – Cretaceous boundary.