west africa impact crater

Christeson G. L., Gulick S. P., Morgan J. V., Gebhardt C., Kring D. A., Le Ber E., Lofi J., Nixon C., Poelchau M., Rae A., Extraordinary rocks from the peak ring of the Chicxulub impact crater: P-wave velocity, density, and porosity measurements from IODP/ICDP Expedition 364. Federal government websites often end in .gov or .mil. Vol. Credit: Nicholson et al., 2022. Estimates for the average flux of Nadir-sized impactors range from once every 100 ka (46) to ~700 ka (2). 1719 N Street, N.W., Washington, D.C. 20036, A 407-million-year-old plants leaves skipped the usual Fibonacci spirals, In Australia, mosquitoes and possums may spread a flesh-eating disease, How Asias first nomadic empire broke the rules of imperial expansion, Four things to know about malaria cases in the United States, Dust from a shrinking Great Salt Lake may be accelerating Utahs snowmelt, The snow forest of North America may be about to shrink, Irrigation may be shifting Earths rotational axis, Neutrinos offer a new view of the Milky Way, A newfound gravitational wave hum may be from the universes biggest black holes, 200 years ago, the Milky Ways central black hole briefly awoke, Quantum computers could break the internet. NASA Pays $10/Hr for Mars Simulation Participants; Entire 378-Day Mission to Pay $60,000, Faint Ripples from Gentle Black Hole Motion Unveils Large-Scale Gravitational Wave Symphony. A newly discovered crater off the coast of West Africa was likely caused by an asteroid more than 400 meters wide that hit the Earth around the same time as the space rock that doomed the . The NWAAM-17 survey in Guinea and Guinea Bissau was acquired in 2017 by TGS in Guinea and Guinea Bissau; data were acquired in 2017 in water depths of 15 to 4600 meters. It would have caused a tsunami up to one kilometer high, as well as an earthquake with a magnitude of 6.5 or so. Vredefort crater in South Africa is the largest known impact crater on Earthalmost 200 miles across! Alvarez L. W., Alvarez W., Asaro F., Michel H. V., Extraterrestrial cause for the Cretaceous-Tertiary extinction. This contact/compression stage is followed by the formation of the central uplift and collapsed transient crater rims during the crater modification stage, resulting in the structural configuration observed including the final elevated crater rims and faulted terraces surrounding a central uplift. (C) North-South seismic profile from the salt basin in the north to the Nadir Seamount, south of the Guinea Fracture Zone. Seismic reflection data from the Guinea Plateau, West Africa, reveal a 8.5-km-wide structure buried below ~300 to 400 m of Paleogene sediment with characteristics consistent with a complex. Scientists are aware of only one such eventknown as an impact clusterin Earths history, and it occurred roughly 460 million years ago. and transmitted securely. Minimum initial water depth estimates for the crater was estimated at 500 m from the height of the Maastrichtian clinoforms. Pickersgill A. E., Mark D. F., Lee M. R., Kelley S. P., Jolley D. W., The Boltysh impact structure: An early Danian impact event during recovery from the K-Pg mass extinction. The location and depth of this low reflectivity zone correspond well to the expected position of a breccia moat and the depth of damage expected for an impact crater of this size (25). The north-east limit of this facies closely corresponds with the Maastrichtian shelf-slope break at the landward margin of the Guinea Terrace. Category:Impact craters of South Africa - Wikipedia Olyphant J. R., Johnson R. A., Hughes A. N., Evolution of the Southern Guinea Plateau: Implications on Guinea-Demerara Plateau formation using insights from seismic, subsidence, and gravity data. The impact occurred southwest of what is now Johannesburg, South Africa, and temporarily made a 40-kilometer-deep and 100-kilometer-wide dent in the surface. The Nadir Crater is situated at or very near the K-Pg boundary, based on our seismic stratigraphic framework for the Guinea Plateau and that of previous studies (17). But researchers have now uncovered another crater off the coast of Guinea that might well be Chicxulubs cousin. A second asteroid may have struck during the dinosaurs' demise South Africa; meteorite impact sites; Vredefort Dome; Parys; Tswaing These suevite would likely have low seismic velocities and be relatively well sorted because of settling within the reflooded crater as observed in Chicxulub [e.g., (30, 32)]. Ukraine's Africa troubles continue after recent leaders - Euronews 1A). The underwater crater, spotted serendipitously in commercial observations of seafloor sediments, is believed to have formed at roughly the same time as the famous Cretaceous-Paleogene impact event. About two billion years ago, an asteroid measuring at least 10 kilometers across hurtled toward Earth. Perhaps Chicxulub and the newly discovered featuredubbed Nadir craterformed from the breakup of a parent asteroid or as part of an impact cluster, the team suggested. National Library of Medicine Thats because impact craters at sea gradually become buried under sediment, Bray says, which makes the Nadir structure a valuable scientific find, regardless of its birthdate. In some of these cases, an elevated crater rim cannot be clearly identified, and the outer brim is considered to be part of the crater itself. The distinct high-amplitude seismic facies between the top Albian and KU1 reflector on the Guinea Terrace likely represent black shale deposits with elevated total organic carbon (TOC), equivalent to those found on the conjugate tectonic margin (19). "The Nadir Crater offshore West Africa: A candidate Cretaceous-Paleogene impact structure". It was less a destroyer of worlds and more of a regional ruiner. Thats what happened 66 million years ago when a roughly 12-kilometer-wide asteroid slammed into a shallow reef in the Gulf of Mexico. Using geologic layers adjacent to Nadir, some with ages obtained by past studies, the team estimated the structure to have formed around the end of the Cretaceous period 66 million years ago. 2C); this sits above a pronounced uplift in the substrate below, with the Top Albian and KU1 horizons elevated ~350 m above regional. Funding acquisition: U.N. Project administration: U.N. Its clearly key to more precisely constrain the age of Nadir crater, Nicholson and his collaborators maintain. "The energy released would have been around 1,000 times greater than that from the January 2022 eruption and tsunami in Tonga.". Until then, everything else is just speculation built upon speculation, said Ludovic Ferrire, a meteorite and impacts expert at the Natural History Museum in Vienna who wasnt involved with the work. But thats around the best they can say. Drilling in the crater for minerals that contain radioactive elements could provide a more precise date of formation, Rampino says. Although the Top Cretaceous (Top Maastrichtian) reflection is well constrained, the precise age of the intra-upper Cretaceous reflections KU1KU4 remains uncertain because of the low amplitude, laterally discontinuous seismic character, and poor seismic quality in the eastern plateau near the exploration wells. The plateau was then part of the Central Atlantic passive margin of West Africa during the Late Jurassic to Early Cretaceous. There are other impact craters close in age to the K-Pg boundary, particularly the large (24 km) Boltysh impact crater in present-day Ukraine, which has an age 65.4 Ma, ~650 thousand years (ka) younger than Chicxulub (64). African Crater Adds an Asteroid Strike to the Late Dinosaur Era Bray V. J., Hagerty J. J., Collins G. S., False peak creation in the Flynn Creek marine target impact crater, http://www-odp.tamu.edu/Publications/prosp/207_prs/207PROSP.PDF. Alternatively, if the Nadir Crater is temporally close to (<1 Ma) but not precisely the same age as Chicxulub, it raises the question as to whether there may have been an impact cluster at the end of the Cretaceous period. "Our simulations suggest this crater was caused by the collision of a 400m-wide asteroid in 500-800m of water," explained Dr Veronica Bray from the University of Arizona, US. The Cretaceous stratigraphy of the Guinea Terrace is separated into a pre- and syn-transform Lower Cretaceous (~145 to 100 Ma ago) sequence and a posttransform Upper Cretaceous (~100 to 66 Ma ago) sequence, separated by the regional Top Albian unconformity (Fig. Then the water evicted from the ocean by the impact would cascade back into the still-forming crater, rush into the middle and splash 6,500 feet into the air before collapsing to create another colossal tsunami. Alkaline volcano of Paleocene age on the Southern Guinean margin: Mapping, petrology, Origin of submarine volcanism at the eastern margin of the central atlantic: Investigation of the alkaline volcanic rocks of the carter seamount (Grimaldi Seamounts). Seismic frequency at the top of the crater is around 45 Hz, and interval velocity is ~1800 m/s, giving a tuning thickness (seismic resolution) of around 10 m. The GWG99 survey in Guinea was acquired in 1999 by WesternGeco in water depths of 150 to 4500 m. Acquisition parameters include a 6-km streamer length towed at a depth of 8 m, with 480 hydrophone channels of 12.5-m group length and a 25-m shot point spacing, giving a 120 full-fold data coverage. Perhaps a similar breakup of a common parent asteroid occurred on Earth 66 million years ago, Nicholson and his colleagues proposed. Movies of full simulations are included in the Supplementary Materials. As a result of the initial impact, a >2-km-high ejecta curtain (8) of water and sediment would form adjacent to the crater (Fig. New Theory Suggests Potential Origin of Space Rock That Ended Dino Species. The number of binary impact structures may, in fact, be even smaller than proposed as a number of these candidates have subsequently been disputed or disproven (10). By contrast, seismic velocities around the periphery (annular trough) at Mjlnir are lower because of brecciation and associated porosity-increasing processes, similar to that also observed in sedimentary and basement rocks at the Chicxulub impact crater (28). Retrieved 18 August 2022. The BBC is not responsible for the content of external sites. 3). 2), which suggests a continuation of relatively deep-water conditions throughout the Cenozoic. The main seismic reflections KU1KU4 are characterized as downlap surfaces that separate individual prograding clinoform sequences (Fig. S.P. The newly discovered Nadir crater appears to have formed right around the same time as that cataclysm. We are grateful to TGS Nopec, Schlumberger, and Office National des Ptroles (ONAP) in Guinea for access to 2D seismic and well data for this study. As well as potential undiscovered craters, there are numerous confirmed craters of approximately Late Cretaceous to Paleogene age where absolute age constraints are absent or have large (106 to 107 years) uncertainty (5). 2010-03-10. About 66 million years ago, Earth was smacked in the face by an asteroid. The Boltysh impact structure: An early Danian impact event during recovery from the K-Pg mass extinction. These features were caused by the collision of large meteorites or comets with the Earth. Seismic shaking of this magnitude would also likely result in substantial mass wasting of the margins of the Guinea Terrace, possibly triggering additional high-amplitude landslide tsunamis (47, 48). Gaza and Israel trade fire as Jenin withdrawal begins, Israel's Jenin operation reignites Palestinian anger, 'For the politicians of France, we are nothing', Cuba turns to old ally Russia to tackle fuel crisis, The battalion of black women erased from history. However, these almost always occur in clusters of several tens to thousands of individual features, and we see no other comparable features anywhere on the Guinea Plateau or any seismic evidence of gas or other fluid escape features. Tswaing, meaning "place of salt" in the Setswana language, is an ancient impact crater outside the metropolis of Pretoria in South Africa 's Gauteng province. The seismic stratigraphic framework is based on an extensive 2D seismic reflection dataset and three industry wells drilled on the southeast of the plateau (Fig. And perhaps most important, theres clear evidence of deformed sedimentscaused by faulting and foldingpersisting hundreds of meters below what would be the crater floor. Impact craters of Africa by country (10 C) Pages in category "Impact craters of Africa" This category contains only the following page. Numerical simulations of crater formation indicate a marine target (~800-m water depth) impact of a 400-m asteroid, resulting in a train of large tsunami waves and the potential release of substantial quantities of greenhouse gases from shallow buried black shale deposits. Structural reconstructions of the preimpact stratigraphy and the geometry of the transient crater were carried out by seismic flattening of the Top Maastrichtian and KU1 horizons, respectively. The terraced floor, subtle central peak and underlying zone of highly deformed rock just below the depression are typical of large impact craters. Environmental issues of Lake Bosomtwe impact crater in Ghana (West Africa) and its impact on ecotourism potential Desmond Ofosu Anim1, 2, 3, Yiping Li1, 2 *, Akosua Korantema Agadzi2, 3, Philip Nti Nkrumah2, 3 1 Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education, Nanjing, 210098, China published 18 August 2022 The crater dates to around 66 million years ago, but may or may not have been related to the dino-killing impact. Massive Impact Crater Beneath the North Atlantic Reveals Dinosaur 10 ka or less Less than ten thousand years old, and with a diameter of 100 m (330 ft) or more. Get the most fascinating science news stories of the week in your inbox every Friday. He and his colleagues estimated that the projectile that plunged into the waters off Africas west coast was a stony asteroid 1,300 feet long, moving at 12 miles per second. The seamounts and other Upper Cretaceous-Paleogene volcanic features on the plateau margin (Fig. The following craters are officially considered "unconfirmed" because they are not listed in the Earth Impact Database. Heres how to save it, may have formed at the same time as Chicxulub, The Nadir Crater offshore West Africa: A candidate, The Boltysh impact structure: An early Danian impact event during recovery from the K-Pg mass extinction, Dinosaur-killing asteroid may have made Earths largest ripple marks, The Age of Dinosaurs may have ended in springtime, Killer Collision: Dino demise traces to asteroid-family breakup, The Amazon might not have a tipping point. But its still in trouble. Orm J., Sturkell E., Nlvak J., Melero-Asensio I., Frisk ., Wikstrm T., The geology of the Mlingen structure: A probable doublet to the Lockne marine-target impact crater, central Sweden. Category. Neither is there any local evidence for a salt diapir at the site of the crater. Prof Sean Gulick, who co-led the recent project to drill into the Chicxulub Crater, said Nadir might have fallen to Earth on the same day. Geologist Uisdean Nicholson of Heriot-Watt University in Edinburgh happened upon the structure while analyzing data collected by seismic waves transmitted underground to detect physical structures offshore of Guinea. Model outcomes show total plastic strain (TPS) on the left and deformed lithologies on the rightthe gray unit represents the assumed Cenomanian-Turonian black shale deposits as a marker horizon. These clusters, if present, are likely formed by multiple impacts from genetically related asteroid families, which form as a result of collision and breakup of larger parent bodies within the asteroid belta process that continues to the present day (14). BBC News. TPS is similar for all water depths, with TPS values >1 to a depth of ~2.5 km below the crater. KU1 and KP1 regionals are schematic reconstructions of these seismic horizons before formation of the crater at the end of the Cretaceous and are used to reconstruct a conceptual model of crater formation (Fig. These results were published in Science Advances. But its too simplistic to assume that a pair of gravitationally bound asteroidsa binary asteroidformed Chicxulub and Nadir crater in a one-two punch, the authors suggested. The crater floor sits 200 m below the regional (predeformation seabed; KP1), with the crater rim elevated 20 to 40 m above this surface. a sunlight-starved impact winter that lasted for years, just 650,000 years after the Chicxulub impact, Neural Networks Map the Ebb and Flow of Tiny Ponds, Collaboration Helps Overcome Challenges in Air Quality Monitoring, What We Know and Dont Know About Climate Tipping Elements, Proudly powered by Newspack by Automattic. Of the preliminary simulations completed so far, it is likely that the material weakening of the central target is too high as the amount of uplift is larger than that shown in the seismic line across the crater. Submarine landslide tsunamis: How extreme and how likely? A. Ivanov, V. N. Kostuchenko, Impact crater formation: Dry friction and fluidization influence on the scaling and modification, in. A version of this article appears in print on, African Crater Adds an Asteroid Strike to the Late Dinosaur Era, https://www.nytimes.com/2022/08/17/science/crater-dinosaurs-africa.html. The initial preimpact stratigraphy is assumed to have been near horizontal (Fig. 1B), which evidently formed during discrete marine transgressive-regressive events during the Late Cretaceous. An asteroidtheres good evidence that the Chicxulub impact was due to an asteroid rather than a cometorbiting Earth could have been torn apart by our planets gravity. Boston MA (SPX) March 5, 2006 - Researchers have discovered the remnants of the largest crater of the Great Sahara of North Africa, which may have been formed by a meteorite impact tens of millions of years ago. Copyright 2023 The Science Times. 2). This potential temporal coincidence with the Chicxulub event in Mexico leaves open a number of possibilities, including that (i) the Nadir impactor may have been part of a binary asteroid or have formed by partial breakup of the larger Chicxulub asteroid that led to the major K-Pg extinction event, or (ii) it may have been part of a longer-lived impact cluster, or (iii) may be causally unrelated to Chicxulub. All the inner bodies in our solar system have been heavily bombarded by meteoroids throughout their history. This sequence stratigraphic framework places the Nadir Crater at or close to the Top Maastrichtian, approximately 66 Ma. These are circular to elliptical features in the seabed and may superficially have a similar surface expression to the Nadir Crater. It appears to me there is also an impact crater several miles in diameter, approximately 40-45 miles to the SE of Tete, Mozambique. The 2D data were acquired and processed by TGS and WesternGeco. Any animals on the shoreline nearby would see another sun, said Veronica Bray, a planetary scientist at the University of Arizona and an author of the study. These events have been linked to periods of major environmental perturbation on Earth (13, 15), suggesting that impact clusters on Earth may be an important hazard despite the lack of a preserved terrestrial record. "The Agoudal (High Atlas Mountains, Morocco) shatter cone conundrum: A recent meteorite fall onto the remnant of an impact site". Society for Science & the Public 20002023. A terraced crater interior and central peak is expected for complex craters and is consistent with the predicted morphology for terrestrial impact craters larger than ~2 to 4 km (24). Scientists hope to drill into a newly discovered impact crater off the west coast of Africa to explore how it's linkedif it isto the famous Chicxulub impact 66 million years ago. Peak temperatures of >1300 K and a peak shock pressure exceeding ~0.5 GPa would likely convert organic matter into methane, and the instantaneous release of methane could have substantial, if short term, environmental consequences; exact quantities of volatile release would be required to assess whether this would be a regional or global effect as well as a determination of timing relative to the larger climatically active gas releases at Chicxulub. We hypothesize that this formed as part of a closely timed impact cluster or by breakup of a common parent asteroid. Thats a curious coincidence, and scientists are now wondering whether the two impact structures might be linked. sharing sensitive information, make sure youre on a federal Vredefort Crater. Impact Craters on Earth - Africa Farouk El-Baz and Eman Ghoneim of Boston University's Center for Remote Sensing made the discovery while studying satellite images of the Western Desert of Egypt. These extend to around 1 km below the preimpact seabed, consistent with seismic observations for the Nadir Crater (Fig. A central uplift develops in all models, although the geometry varies significantly with varying water depths between modelsthe greater the water depth, the larger the central uplift height (relative to preimpact elevation), presumably due to the additional rebound of the exposed rocks after removal of the greater overburden pressure of a deeper ocean. 66 million years ago, around the same time the Chicxulub impact crater formed, an asteroid at least 400 meters wide crashed into Earth near the Nadir seamount off the coast of West Africa. Impact Craters.
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