Some scientists have interpreted these platinum anomalies to be of volcanic origin (Sun et al, 2020). The material appears to be consistent the climatic conditions of the Late Pliocene to Early Pleistocene. An artist's rendition of the hypothesized spread of freshwater into the north Atlantic, resulting from the impact of a meteor on the Greenland Ice Sheet and subsequent melting of great quantities of ice. Dr. Fudge isnt responsible for GIGOism by his co-authors. Laboratory examination revealed that these sediment samples contained shocked quartz and elevated platinum-group-element concentrations, both signs that the sediment records evidence of the impact of an iron asteroid more than one kilometer wide. It most likely happened during times when the climate was warm and sea level was high, possibly 400,000 years ago. (Image credit: University of Copenhagen) Local impact. As per scaling laws (Johnson et al., 2016b), to form a 31 km in diameter impact structure, an iron asteroid impacting at 17 km s1 at an incidence angle of 45 would have to be nearly 2 km wide (Collins et al., 2004). Nature493,489494 (2013). In fact, a new study published in the journal Science Advances today reports its age to be 58 million years old. Ourpeer-reviewed studywas published on March 15 inProceedings of the National Academy of Sciences. The YDIH was hatched (or revived) in 2007, when the route of meltwater outrush that caused the YD wasnt know. The odds of a once in two million year event occurring in the past 12,000 years are 167 to one against. Deglaciation of North America. A version of this article appears in the April 9, 2022 issue of Science News. Subsequently, a team of scientist at Germany's Alfred Wegener Institute flew an airborne survey over the region in the spring 2016, using a new ultrawideband radar sounder developed by the Center for Remote Sensing of Ice Sheets at The University of Kansas. According to a news release by the University of Copenhagen, an analyses performed on grains of sand and rocks washed by meltwater from the crater site to the edge of the glacier, the Hiawatha impact crater is far older. A.,Fahnestock, M. A.,Catania, G. A.,Paden, J. D.,Prasad Gogineni, S.,Young, S. K.,Rybarski, S. C.,Mabrey, A. N.,Wagman, B. M.andMorlighem, M.(2015),Radiostratigraphy and age structure of the Greenland Ice Sheet. J. Geophys. would be approriate were he a GIGO computer gamer or tamperature adjuster rather than an ice core analyst. 3 Ma Beaufort Formation at Meighen Island, Canada (Fyles et al., 1991). The YD has been called Heinrich Event 0, although the 8.2 Ka Event might merit that designation, or -1. Greenland has been at a high latitude for a long time. A red cylinder shows the best-fit rim of the impact crater and a measuring stick shows that the diameter of the crater is more than 31 kilometers across. Theres an Objectively Measured Earth Surface Temperature, U.S. Could the asteroid have slammed into Earth as recently as 13,000 years ago, when humans had long populated the planet? The name is funny, particularly for a scientist . Effect of ice sheet thickness on formation of the Hiawatha impact crater.Earth and Planetary Science Letters,566:116972 [10.1016/j.epsl.2021.116972]. This site will not work correctly with javascript disabled. The crater formed when an iron meteorite more than half a mile wide smashed into northwest Greenland but the timing of when the event happened remains a key question and one the researchers want to answer next. While not directly related to the Hiawatha Crater, I ran across another very interesting new bit of research on the Camp Century ice core. The sand was analyzed at the Natural History Museum of Denmark by heating the grains with a laser until they released argon gas, whereas the rock samples were analyzed at the Swedish Museum of Natural History using uranium-lead dating of the mineral zircon. ClimateTV: Live at 1PM ET UN Plans Climate Power Grab Over U.S. WEF: We Need Moonshots to Solve the Climate Crisis, If Were Going to Act Like Insects, Lets At Least Be Smart About It, SMH: [AU] $300 trillion is needed to stop global warming, and thats a bargain, Wind Turbine Power and Land Cover Effects on Bat Deaths, UAH Global Temperature Update for June, 2023: +0.38 deg. Image credit: Pierre Beck. Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site. Radiostratigraphy and age structure of the Greenland Ice Sheet. The Hiawatha impact crater is potentially one of the youngest large impact craters on Earth.Visualizers: Cindy Starr (lead), Greg Shirah, Lori Perkins, Ernie WrightFor more information or to download this public domain video, go to https://svs.gsfc.nasa.gov/4572#82032 The material was too old to be reliably 14C dated. These layers visible in the radar curtain record the history of the ice sheet from the oldest ice near the bed to the recent year's layers found near the surface. Ice-penetrating radar sends radio waves downward into the ice sheet and measures the energy reflected back from within the ice sheet and the ground beneath. That mission has never been more important than it is today. Bond & Lotti 1995 Origin and Age of the Organic MatterOur observations and analyses of the organic carbon in front of the Hiawatha Glacier show that it stems from organic-rich beds formed at a time when tree growth at this high northern latitude was possible. Digital Elevation Model showing the Hiawatha impact crater beneath the ice of Greenland. The animation ends with a view of the Arctic, Greenland and Europe.This video is also available on our YouTube channel. As the plane flies inland over Hiawatha Glacier, the ice sheet is cut away, leaving the radargram on the interior cutting plane. A publication noted in 1952 that Hiawatha Glacier had . The only clear evidence for a recent (past 29 ka) impact found in Greenland (so far) is the platinum anomaly in the GISP2 ice core (Petaev et al., 2013); although this does not necessarily mean the impact occurred in Greenland. The Eemian apparently melted only about 25% more of the GIS Southern Dome than has the Holocene so far, while barely affecting its Northern Dome. So the evidence remains equivocal. The reflected data depicts the historical layers in the ice that were generated by the annual seasonal cycles of growth and melt. While a more recent impact cannot be absolutely ruled out; there should have been evidence for it in the Camp Century ice core. As such, I'm convinced that we've determined the crater's actual age, which is much older than many people once thought," says Michael Storey, co-author of the study. This video shows how that discovery came together. 1) ( Kjr et al., 2018 ). Why the recently discovered Hiawatha Crater in Greenland is not the Younger Dryas impact. Sci Rep7,44031 (2017). This image shows another view of some radar data from the airborne survey of the Hiawatha crater displayed on opaque curtains. Just less icebergs as is logical since the deglaciation was quite advanced. I just had to take proving or disproving the YDIH out of the equation. Younger Dryas also sticks out because it was preceded by the very warm Blling/Allerd interstadial. The new crater is about 22 miles (36 km) across, which makes it the 22nd-largest impact crater ever discovered on Earth and a wee bit bigger than the Hiawatha crater, which measures 19. Oh, you mean like his co-author Eric Steig. Earth Surf.,120:212241. doi:10.1002/2014JF003215. A large impact crater beneath Hiawatha Glacier in northwest Greenland. hiawatha_shp - zip, 4.26 kB: Archive of shapefiles (WGS84 latitude/longitude) containing crater rim picks, central uplift picks, and best-fit rim and center. Ever since 2015, when researchers at the University of Copenhagen's GLOBE Institute discovered the Hiawatha crater combining RADAR data with gravity and magnetic surveys, uncertainty about the crater's age has been the subject of considerable speculation. Pleistocene platinum anomalies have also been identified in North America (Moore et al., 2017) and South Africa. . That should drive the eco-looney crazier. 3. I make my contribution by avoiding fizzy champagne and fizzy beer at all costs. Christ, A.J., Bierman, P.R., Schaefer, J.M., Dahl-Jensen, D., Steffensen, J.P., Corbett, L.B., Peteet, D.M., Thomas, E.K., Steig, E.J., Rittenour, T.M., Tison, J-L., Blard, P-H., Perdrial, N., Dethier, D., Lini, A., Hidy, A.J., Caffee, M., Southon, J., in press, A multi-million-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century,The Proceedings of the National Academies of Sciences of the United States of America. 2020. Part of this edge (top of photo) and a tongue of ice that breaches the crater's rim are shown in this photo taken during a NASA Operation IceBridge flight on April 17. Credit: NASA/John Sonntag Hiawatha Glacier attracted attention in 2018 because of the discovery of a crater beneath the surface of the ice sheet in the area. A still image of the crater beneath the Hiawatha Glacier, outlined with a semi-transparent red cylinder. The frozen soil was examined, set aside and then forgotten. Two of the authors discussed it in in this article: Ancient leaves preserved under a mile of Greenlands ice and lost in a freezer for years hold lessons about climate changeAndrew Christ & Paul Bierman, March 15, 2021. The bed topography under the ice clearly shows the Hiawatha crater. The size of the crater suggests that its formation likely caused significant regional and perhaps even global environmental perturbations (Toon et al., 1997; Erickson et al., 2020). For now, the researchers say, what impact this space punch may have had on Earths global climate remains a mystery. Sun, N., Brandon, A.D., Forman, S.L., Waters, M.R., Befus, K.S., 2020. Since we dont know if the Pleistocene organic material came from trees and other biomass incinerated by the impact 2.4 Ma or were the remains of plants buried under the ice sheet and incinerated more recently by an impact event, we cant fix the minimum age from these data. Its like when people say that Yellowstone is overdue for a super-eruption Each occurrence is statistically independent. This would not be the case if impact had significantly melted and/or disrupted the Late Pleistocene ice sheet at Camp Century. The crater is big enough to contain the entire city of Washington D.C. During the impact high-pressure and high-temperature minerals, like zircon, formed in the rocks surrounding the impact site. If course stats dont rule having a couple of such events a 100yrs apart. Credit: Natural History Museum of Denmark, Cryospheric Sciences Lab, NASA Goddard Space Flight Center The crater was left when an iron asteroid 1.5 kilometers across slammed into Earth, possibly within the past 100,000 years. I see that later the date of the Silber paper is shown as 2021. 12,900 cal B.P. Based on a range of plausible ice-flow parameters, three scenarios were developed for each site: low, moderate, and high, where the names reflect the relative magnitude of accumulation in the glacial and early Holocene. The Hiawatha impact crater could swallow up Washington DC and is larger than about 90% of the roughly 200 previously known impact craters on Earth. Scientists spotted the crater in 2015 during a scan by NASAs Operation IceBridge, which used airborne radar to measure the ice sheets thickness. The recent discovery of a large, probably young, impact crater beneath the edge of the Greenland Ice Sheet (Kjr et al, 2018) was quite remarkable. If the impact occurred during the the latter part of the last glacial stage of the Pleistocene, it had no effect on the ice sheet just a few 10s of kilometers away. However, the ice sheet would have muted the effects of the impact. A red cylinder shows the best-fit rim of the impact crater and a measuring stick shows the diameter as more than 31 kilometers across. Lithic grains and detrital carbonate deposits in the mid-Atlantic indicate there were iceberg armadas during the YD. Science at VILLUM (@VILLUMscience) March 10, 2022 According to a statement from the University of Copenhagen, the team of researchers independently sampled the rocks from the crater and dated. Here the radar data is displayed on curtains in the location where it was observed showing the layers in the ice that record the history of the ice sheet similar to the way that rings on a felled tree show the growing seasons in a tree trunk. Strange . This is the SVS Demo Reel presented at SIGGRAPH 2019 in Los Angeles, CA. "It is fantastic to now know its age. Pebbles near the Hiawatha impact crater in northwestern Greenland contain grains of zircon (one at left) that contain many tiny crystals, some altered by the impact (right). The early Pleistocene, 2.4 Ma, Kap Kbenhavn Formation in North Greenland is the youngest known occurrence of forest at these high latitudes (see Funder et al. Here the topogr. [2001] regarding the 2.4 Ma age determination), and the absence of Pinus does not preclude contemporaneous growth in Inglefield Land some 200 km to the south. The deep ice cores are marked with magenta triangles. A.,Fahnestock, M. A.,Catania, G. A.,Paden, J. D.,Prasad Gogineni, S.,Young, S. K.,Rybarski, S. C.,Mabrey, A. N.,Wagman, B. M.andMorlighem, M.(2015),Radiostratigraphy and age structure of the Greenland Ice Sheet. The 22-mile wide feature would be the second crater found under an ice sheet, and if confirmed, would be the 22nd-largest crater on Earth. Dyke et al., 2003 and Dyke 2004 present an excellent set of ice front maps over North America during the deglaciation period. The Greenland ice sheet survived through all of human history during the Holocene, the present interglacial period of the last 12,000 years, and most of the interglacials in the last million years. First, we usedclean room chemistryand aparticle acceleratorto count atoms that form in rocks and sediment when exposed to natural radiation that bombards Earth. Thackeray, J. Francis; Scott, Louis; Pieterse, P. The Younger Dryas interval at Wonderkrater (South Africa) in the context of a platinum anomaly. The flight lines from the survey of the area are shown in green. A green grid fades in over the surface of ice sheet showing the location of the flights that collected the radar data in spring 2016 by AWI. They were constructed from ice penetrating radar profiles (MacGregor et al., 2015). Invest in quality science journalism by donating today. I contribute to beneficial global greening by not immediately consuming the CO2 in beer and champagne. I will go jump in my SUV and drive around the neighborhood a few laps, trying to stave off the real tipping point. An outline of North American deglaciation with emphasis on central and northern Canada. Reconstructions of mean-annual Greenland temperature and precipitation for the past 20,000 years and the ice-core records used to create the reconstructions 2020. This circular structure is relatively shallow and exhibits a small central uplift, whereas a peak-ring morphology is expected. 10.1126/sciadv.aar8173. John posted: The odds of a once in two million year event occurring in the past 12,000 years are 167 to one against.. Hiawatha Crater: Bracketing the Age 2 years ago David Middleton Guest "Don't mention the YDIH (wink, wink, nudge, nudge) " by David Middleton The recent discovery of a large, probably young, impact crater beneath the edge of the Greenland Ice Sheet (Kjr et al, 2018) was quite remarkable. Since then, we have been on several field trips to the area to collect samples associated with the Hiawatha impact," says Professor Larsen. The asteroid smashed into Earth, leaving a thirty-one-kilometer-wide and one-kilometer-deep crater. A still image showing a comparison of the size between the Hiawatha crater and Paris, France. Geology2020;; 48 (9): 867871. They were constructed from ice penetrating radar profiles (MacGregor et al., 2015). Could the impact have occurred between the Camp Century ice-free periods (~1.4 to 0.9 Ma)? The Hiawatha impact crater in Greenland, as depicted by NASA's Scientific Visualization Studio. The manner in which these scientists tie the ice cores into the radar profiles and interpret the ice sheets internal structure and stratigraphy is very analogous to the way we tie well logs into seismic profiles and interpret the structure and stratigraphy of Earths subsurface. Introduction Recently, a putative impact crater with the diameter of 31.1 0.3 km was discovered beneath the Hiawatha Glacier in northwestern Greenland ( Fig. Science Advances. Large Pt anomaly at the onset of the Younger Dryas. Labels indicate layers in the ice sheet. A still image showing a comparison of the size of the Hiawatha crater to Washington, DC. The Hiawatha impact crater is shown in northwest Greenland (left); the crater is clearly visible (right) beneath the surface of the ice. if, say, 50 million years have passed without occurrence of a once-in-two-million year event, most people would say we are overdue for such occurring, with inference that such event has a probability of happening in the next 12,000 years significantly higher than one-in-167. While they couldnt categorically rule out a Late Pleistocene impact on the ice sheet, they concluded that rocky ejecta fragments should have been found in the Camp Century ice core; and so far, no ejecta material has been found. At the very end, they pulled up something else 12 feet of frozen soil. This is still not the crater you are looking for. Computer [+] generated image based on data by NASA. The powerful impact that created a mysterious crater at the northwestern edge of Greenlands ice sheet happened about 58 million years ago, researchers report March 9 in Science Advances. Kinda like the way Californians talk about the next big one when discussing earthquakes. The dating ends speculation that the. Getting back to the Hiawatha Crater, Garde et al., 2020 (many of the same authors of Kjr et al., 2018) identified organic material, including charcoal and lignite, in the outwash from the crater. The radar data ("radargrams") is then displayed on curtains in the location where it was observed showing the layers in the ice. This video is also available on our YouTube channel. A still iamge showing the distance across the Hiawatha crater. The radar data is shown on the facing removed surface. (2018) further asserted that the putative impact crater may have been formed by a fairly rare iron asteroid. Dyke, A.S., Moore, A. and L. Robertson. However, the ice sheet would have muted the effects of the impact. The radar data detects layers in the ice generated by climate events in the past. Hiawatha Glacier is a glacier in northwest Greenland, with its terminus in Inglefield Land. Volcanic origin for Younger Dryas geochemical anomalies ca. Eemian interglacial reconstructed from a Greenland folded ice core, Large Pt anomaly at the onset of the Younger Dryas, Effect of ice sheet thickness on formation of the Hiawatha impact crater.. In 1963, inside a covert U.S. military base in northern Greenland, a team of scientistsbegan drillingdown through the Greenland ice sheet. Since we dont know if the Pleistocene organic material came from trees and other biomass incinerated by the impact 2.4 Ma or were the remains of plants buried under the ice sheet and incinerated more recently by an impact event, we cant fix the minimum age from these data. 12 March 2022 Catastrophism Danish and Swedish researchers have now dated the giant Hiawatha crater, 31 km wide, discovered in Greenland, back in 2015. Its ending was very abrupt because it was terminated by a Dansgaard-Oeschger event. Thackeray, J. Francis; Scott, Louis; Pieterse, P. The Younger Dryas interval at Wonderkrater (South Africa) in the context of a platinum anomaly. Download [6] The bedrock within the region of this structure consists of 1.985 to 1.740 billion year old Paleoproterozoic felsic igneous rocks and paragneiss. Besides which, slight warming is a good thing, in addition to the beneficial greening of the planet. Hiawatha Glacier is a glacier in northwest Greenland, with its terminus in Inglefield Land. Two of the authors discussed it in in this article: Ancient leaves preserved under a mile of Greenlands ice and lost in a freezer for years hold lessons about climate changeAndrew Christ & Paul Bierman, March 15, 2021. But our research shows that at least one of these interglacial periods was warm enough for a long enough period of time to melt large portions of the Greenland ice sheet, allowing a tundra ecosystem to emerge in northwestern Greenland. Getting back to the Hiawatha Crater, Garde et al., 2020 (many of the same authors of Kjr et al., 2018) identified organic material, including charcoal and lignite, in the outwash from the crater. Could its impact have catalyzed a nearly 1,000-year period of global cooling known as the Younger Dryas? Their modeling indicated if the impact occurred on a relatively thick ice sheet (>1.5 km), the ejection of rocky material would be inhibited, possibly explaining why no fragments have been identified in any of the deep ice cores. In the maps below, on the two leftmost panels, Hiawatha Crater is marked by the yellow dot, with a red outline. An impact at the onset of the Younger Dryas cant be categorically ruled out. 2. The temperature values are anomalies with respect to the reference period, 1850-2000 CE, while the precipitation values are fractional precipitation rates with respect to the same reference period. 3 Ma Beaufort Formation at Meighen Island, Canada (Fyles et al., 1991). Thanks! Late Pleistocene platinum anomalies have also been identified in North America (Moore et al., 2017) and South Africa (Thackeray et al., 2019). Half a century later, scientists rediscovered that soil in a Danish freezer., With their dependence on offshore wind power and ~$0.40/kWh electricity rates, I was impressed to see that it was still plugged in and running . Silber et al., 2012 (manuscript) modeled impacts on an ice-free surface and varying ice sheet thicknesses and found the crater to be consistent with an impact between 2.6 million and 11,700 years ago. Pebbles at the edge of Greenlands ice sheet, shown here in 2019, contain zircon crystals that were altered by an impact about 58 million years ago. Photo from fieldwork at the edge of the Greenland Ice Sheet in 2019. [3] Hiawatha Glacier attracted attention in 2018 because of the discovery of a crater beneath the surface of the ice sheet in the area. . Any ejecta found in sea floor sediments might give another angle on date and may confirm or refute the idea that the ice thickness suppressed any ejecta. Curtains of radar data closest to the camera are sequentially removed as we fly through the crater basin in order to give a close-up view of the interior layers of ice. They also estimated the size and composition of the asteroid. While not directly related to the Hiawatha Crater, I ran across another very interesting new bit of research on the Camp Century ice core.
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