Crossey, L. J., Kudo, A. M., McCarville, P. 1994. Hartung, J. by: Charles O’Dale. A meteorite about a mile in diameter formed the Manson impact crater (shown in red) at the end of the Cretaceous period. Proceedings of the VIIth International Symposium on the Observation of the Continental Crust Through Drilling, Sante Fe, New Mexico, pp. Post-impact hydrothermal alteration of the Manson impact structure (abstract). Manson Crater - The Manson, Iowa, impact crater is not only one of the largest US impact craters, at about 35 km in diameter, it is one of the best known and best studied. B. and Anderson, R. R. 1990. Abstracts of the 25th Lunar and Planetary Science Conference, pp. Bunte breccia-like deposits within the Manson impact structure (Iowa); evidence for impact into a shallow marine environment? 12, pp. Science, v. 262, no. Boer, R. H., Reimold, W. U., Koeberl, C. and Kesler, S.E. Largest Crater in the United States. Abstracts of the 24th Lunar and Planetary Science Conference, pp. Nature, v. 340, pp. See more ideas about impact crater, crater, earth. Although the lab is regularly called upon to perform well water testing, the area where the incident occurred made the case unusual, said Terry Cain, … 40Ar/39Ar age spectra of shocked K-feldspar suggests K-T boundary age for Manson, Iowa, impact structure (abstract). Steiner M. B. and Shoemaker, E. M., 1996, A hypothesized Manson impact tsunami: Paleomagnetic and stratigraphic evidence in the Crow Creek Member, Pierre Shale. Planar deformation features in quartz grains from the Manson impact structure, Iowa (abstract). Meteor Crater (Barringer Meteorite Crater) formed 50,000 years ago when an asteroid plunged through the Earth’s atmosphere and crashed into what would become central Arizona. Premo, W. R., 1992, Nd-Sr isotopic signature of the Pierre Shale: Target material at the Manson impact site and source of the Haitian tektites (K-T Boundary)? 383-396. doi: http://www.lpi.usra.edu/meetings/metsoc98/pdf/5164.pdf, http://www.sciencedirect.com/science/article/pii/S003101829700045X, http://specialpapers.gsapubs.org/content/307/89.abstract, http://www.iowadnr.gov/portals/idnr/uploads/Iowa%20Outdoors%20Magazine/Nature/files/DayIowaI. 1993. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1177.pdf. Structure of the terrace terrane, Manson Impact Structure, Iowa, interpreted from high-resolution, seismic reflection data. Unlike many impact sites that are completely unknown to the people living within or above them, the town of Manson actually holds an annual Greater Crater … Origin of impact melt breccias and suevites in drill cores from the Manson impact structure determined from mixing calculations (abstract). Abstracts of the 22nd Lunar and Planetary Science Conference, pp. Abstracts of the 1993 Meteoritical Society Annual Meeting. Hartung, J. subject of significant study through drilling. These ash beds, called bentonites, contain sanidine feldspar and biotite that has been dated using the 40Ar/39Ar technique. The Earth Impact Database lists the crater as preserved in metamorphic rock, and as about 73.8 million years old. 835-836. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1419.pdf, Leroux, H.and Doukhan, J-C. 1996. (If links to articles don't work, don't give up. Izett, G. A., Cobban, W. A., Obradovich, J. D., and Dalrymple, G. B. 6, pp. 1993. These appear as thin paral- Part 1: A-F; p 351-352. The remains of a 1.5 mile-wide, 10 billion-ton meteorite are causing problems for a small Iowa … 1992. 1992. First, each age is based on numerous measurements; laboratory errors, had there been any, would be readily apparent. Manson lies near the center of a 24 mile wide crater that was created 74 million years ago when a meteorite crashed to earth. 325-327. doi:10.1038/364325a0. Other significant evidence: (just about everything that you could ask for) breccia, megabreccia, diaplectic and melt glasses, cores with detailed petrographic analysis, morphology, detailed geologic mapping, and so on. 4-7. Crossey, L. J., and McCarville, P. M. 1994. Geological Society of America Special Paper 302, pp. The reworked assemblage decreases in abundance upward through the marlstone, a pattern consistent with an origin involving gravitational settling rather than marine transgression. 235-243. doi: 10.1130/0-8137-2302-7.235, http://specialpapers.gsapubs.org/content/302/235.abstract, Reagan, M. K., Foster, C. T., Jr. and Bell, M. S., 1993, Origin of the upper crystalline-clast bearing suevite in the Manson M-1 core (abstract). Abstracts of the 19th Lunar and Planetary Science, pp. These melted crystals, and therefore the impact, have been dated by the 40Ar/39Ar method at 74.1 Ma (million years; Izett and others 1998), but that is not the whole story by a long shot. B., Roddy, D. J. and Shoemaker, E. M. 1992. 433-456. doi: Zeitler, P., 1996, 40Ar/39Ar thermochronology of shocked feldspars from the Manson impact structure. The geology and geochemistry of ancient groundwater in the central peak aquifer of the Manson impact structure, Iowa (abstract). Meteoritics, v. 27, issue 5, pp. Ancient meteorite standing between one Iowa town and its water supply. Seismic reflection analysis of the Manson Impact Structure, Iowa. Abstracts from the 1994 Meteoritical Society Annual Meeting, Meteoritics, v. 29, no. 31-32. http://adsabs.harvard.edu/full/1994LPI....25...31A. pp. The three worst tornado disasters in the history of Iowa (in terms of deaths) have all been "northwest" tornadoes: Camanche (1860), Grinnell (1882), and Pomeroy (1893). 3, pp. It was one of the biggest impacts by an object from outer space to happen in North America and was previously thought to have led to the extinction of the dinosaurs until age dating tests proved that Manson Crater was too old. Meteoritics, v. 28, no. 1994. In 1991 and 1992, the Iowa Geological Survey Bureau and U.S. Geological Survey began to investigate the possibility that the Manson impact was a Cretaceous-Tertiary (KT) boundary event. B. and Anderson, R. R. 1988. 89-104. doi: 10.1130/0-8137-2307-8.89, http://specialpapers.gsapubs.org/content/307/89.abstract. Jolliff, B. L., Korotev, R. L., Rockow, K. M. and Haskin, L. A. B., 1996, Gravity investigation of the Manson impact structure, Iowa. Petrography of the crystalline breccias from the Manson M-1 core: Implications for impact breccia emplacement (abstract). 1998. Re-Os isotope systematics as a diagnostic tool for the study of impact craters and distal ejecta. Mar 23, 2016 - Impact Craters around the globe. The State Hygienic Laboratory was one of several agencies called to respond to a well water incident in May in Calhoun County. 499-500. doi:10.1111/j.1945-5100.1994.tb00616.x. 6-7. http://www.crewes.org/ForOurSponsors/ResearchReports/1996/1996-34.pdf, Witzke B. J. and Anderson, R. R., 1996, Sedimentary-clast breccias of the Manson impact structure. 39-57. http://s-iihr34.iihr.uiowa.edu/publications/uploads/SR-02.pdf, Witzke, B. J., Hammond, R. H. and Anderson, R. R., 1996, Deposition of the Crow Creek Member, Campanian, South Dakota and Nebraska. Abstracts of the 26th Lunar and Planetary Science Conference, pp. The area of north-central Iowa around the town of Manson has been known as a region of anomalous geology since the early part of the century, when samples collected during the drilling of a Manson town water well proved to be unlike other rocks in the area. Abstracts of the 19th Lunar and Planetary Science, pp. AGU, Vol. Izett, G. A., Reynolds, R. L., Rosenbaum, J. G. and Nishi, J. M. 1993. Keiswetter, D. A., Black, R., Steeples, D. W. and Anderson, R. R. 1993. 347-376. doi: Pernicka, E., Kaether, D. and Koeberl, C., 1996, Siderophile element concentrations in drill core samples from the Manson crater. DOI: 10.1126/science.262.5134.729, http://www.sciencemag.org/content/262/5134/729. 497-498. http://www.lpi.usra.edu/meetings/lpsc1992/pdf/1247.pdf, Hartung, J. In late June 1979, a major tornadic outbreak occurred in Min­ nesota and Iowa, damaging Algona and devastating Manson, Iowa. 89-104. doi: Varricchio D. J., Koeberl C., Raven R. F. Wolbach W. S., Elsik W. C., and Miggins D. P., 2010, Tracing the Manson impact event across the Western Interior Cretaceous Seaway, Geological Society of America Special Paper 465, pp. Geological Society of America Special Paper 302, pp. GSA Bulletin, v. 110, no. Abstracts of the 24th Lunar and Planetary Science Conference, p. 705-706. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1354.pdf. 1-29. doi: 10.1130/0-8137-2302-7.1, http://specialpapers.gsapubs.org/content/302/1.abstract. The Manson Meteor Crater Eastern Iowa Observatory & Learning Center, Linn County Saturday, April 2, 2011. Hartung, J. 1996. A brief history on investigations of the Manson impact structure. v. 68, issue 44, p. 1514. doi:10.1029/EO068i044p01209., http://onlinelibrary.wiley.com/doi/10.1029/EO068i044p01209/full, Kunk, M. J., Izett, G. A., Haugerud, R. A. and Sutter, J. F. 1989. 1099-1100. http://www.lpi.usra.edu/meetings/lpsc1992/pdf/1541.pdf, Reagan, M. K., Foster, C. T., Jr., Bell, M. S. and Anderson, R. R., 1994, Preferential feldspar comminution in suevites from the Manson Impact Structure (abstract). Eischeid #1 Deep Petroleum Test, Carroll County, Iowa,  Iowa Department of Natural Resources Geological Survey Bureau, Special Report Series no. Geological Society of America Special Paper 302, pp. Without such evidence, a geological structure is not a confirmed impact crater. Anderson, R. R., Witzke, B. J. and Hartung, J. 40Ar-39Ar Dating of the Manson Impact Structure: A Cretaceous-Tertiary Boundary Crater Candidate. The fossils, when combined with geologic mapping, allow the various exposed sections of the Pierre Shale to be pieced together in their proper relative positions to form a complete composite section (Figure 1). 351-352. Manson's annual celebration is called "Greater Crater Days" in honor of the much-studied yet invisible crater. 105-113. doi: 10.1130/0-8137-2302-7.105, http://specialpapers.gsapubs.org/content/302/105.abstract. During this time, meteor crater research was unsophisticated and misunderstood. Geological Society of America Special Paper 302, pp. Science, v. 262, no. Iowa Meteorite Crater: Long-Hidden 'Decorah Impact Structure' Revealed Buried beneath the rocks, dirt, buildings and roads of the city of Decorah, Iowa, lies a 470 million-year-old meteorite crater. Abstracts of the 26th Lunar and Planetary Science Conference, pp. The heat of the impact melted some of the feldspar crystals in the granitic rocks of the impact zone, thereby resetting their internal radiometric clocks. Abstracts of the 24th Lunar and Planetary Science Conference, pp. Geological Society of America Special Paper 302, pp. It is now known that the meteor that struck current day Manson, IA happened 20 … 1119-1122,  doi: 10.1130/G24209A.1, http://geology.gsapubs.org/content/35/12/1119.abstract. Bell, M. S., Reagan, M. K., Anderson, R. R., and Foster, Bell, M. S., Reagan, M. K., Anderson, R. R., and Foster, C. T., Jr., 1994, Compositions of minerals in, Blum, J. D., Chamberlain, C. P., Higston, M. P., Koeberl, C., Marin, L. E., Schuraytz, C. and Sharpton, V. L. 1993. 203-207.. The Manson Impact Crater in Iowa is big — like 38km in diameter big. 5134, pp. Size and distribution of shocked mineral grains in the Pierre shale (Late Cretaceous) of South Dakota related to the Manson, Iowa, impact event (abstract). The terminal Cretaceous Manson impact structure in north-central Iowa: a window into the late Cretaceous history of the eastern margin of the Western Cretaceous Seaway, in Geological Society of America Special Paper 287, Perspectives on the eastern margin of the Cretaceous Western Interior Basin, pp. Fluid inclusion studies on drill core samples from the Manson impact crater: Evidence for post-impact hydrothermal activity. This investigation identified the Manson Structure as a “complex” impact crater; that is, it includes an outermost “terrace” of down-dropped blocks, an inner “central peak,” and a “crater moat” in between. Abstracts of the 25th Lunar and Planetary Science Conference. Today the area above the crater is completely flat; however, dozens of feet beneath the soil sits a giant crater and remnants of a meteorite. Geological Society of America.. (abstract). There are three important things to note about these results. The Journal of Geology, v. 66, no. The crater's existence was first discovered during an oil-drilling wildcatting expedition in the 1930s. Abstracts from the 1994 Meteoritical Society Annual Meeting, Meteoritics, v. 29, no. Mineralogical, petrological, and geochemical studies of drill cores from the Manson impact structure: A progress report (abstract). Unfortunately, this impact crater is very old by human standards, since it occurred nearly 75 million years ago. The remains of a 1.5 mile-wide, 10 billion-ton meteorite are causing problems for a small Iowa town, 74 million years after it crashed onto the Earth's surface at 45,000 miles per hour. Proceedings of the 22nd Lunar and Planetary Science Conference, pp. 89-104. doi: Reagan, M. K., Foster, C. T., Jr. and Bell, M. S., 1993, Origin of the upper crystalline-clast bearing suevite in the Manson M-1 core (abstract). Abstracts of the 24th Lunar and Planetary Science Conference, pp. Geological Society of America Special Paper 302, pp. Zeitler, P. K. and Kunk, M. J., 1993, Age and thermochronology of K-feldspars from the Manson impact structure (abstract). Jones, M. C., McCormick, G. R. and Anderson, R. R. 1996. Geological Society of America Special Paper 302, pp. Abstracts of the 26th Lunar and Planetary Science Conference, pp. 211-214. Because of the crater’s young age and the dry climate Meteor Crater is the best preserved impact crater … All rights reserved. A research investigation was started in 1955, and it was labeled a “cryptovolcanic structure” (a hypothetical volcanic steam explosion). 693-694. http://www.lpi.usra.edu/meetings/lpsc1995/pdf/1347.pdf. 331-339. doi: McCarville, P. and Crossey, L. J. An upper Campanian in situ nannofossil assemblage with a lower Campanian reworked assemblage (from older Niobrara Chalk) occurs in the Crow Creek at most localities. Manson impact structure, Iowa: First geochemical results for drill core M-1 (abstract). Anderson, R. R., Witzke, B. J., Hartung, J. These melted crystals, and therefore the impact, have been dated by the 40Ar/39Ar method at 74.1 Ma (million years; Izett et al 1998). The remains of a 1.5 mile-wide, 10 billion-ton meteorite are causing problems for a small Iowa town, 74 million years after it crashed onto the Earth's surface at 45,000 miles per hour. Manson Crater - The Manson, Iowa, impact crater is not only one of the largest US impact craters, at about 35 km in diameter, it is one of the best known and best studied. Post-impact hydrothermal alteration of the Manson impact structure. Geological Society of America Special Paper 302, pp. Meteoritics, v. 28, no. B., Reagan, M. K., Bell, M. S. and Plocher,O. The reason for the difficulty in finding a new well could date back millions of years; a meteor struck an estimated 74 million years ago, creating what's known as the Manson impact crater… 4. pp. Abstracts of the 26th Lunar and Planetary Science Conference, pp. Researchers believed at one time that this meteorite caused the deaths of the dinosaurs. Another nice non-technical article is at: http://www.iowadnr.gov/portals/idnr/uploads/Iowa%20Outdoors%20Magazine/Nature/files/DayIowaIgnited.pdf. The geology and geochemistry of ancient groundwater in the central peak aquifer of the Manson impact structure, Iowa (abstract). Iowa also boasts another hidden impact crater, the enormous 15 kilometre in diameter Manson crater in Humboldt County. 1996. On Mr. Peacock’s latest adventure, they discovered a hidden treasure of the Manson Crater in Manson Iowa. Many popular and scientific articles have been written on the location. 135-136. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1068.pdf. in: The Amoco M.G. B., 1996, Gravity investigation of the Manson impact structure, Iowa. Geological Society of America Special Paper 302, pp. Global Catastrophes in Earth History, Geological Society of America, Special Paper 247, pp. Abstracts of the 23rd Lunar and Planetary Science Conference, pp. (1987), Manson structure team will help guide research, Eos Trans. 347-376. doi: 10.1130/0-8137-2302-7.347, http://specialpapers.gsapubs.org/content/302/347.abstract. Preliminary clay-mineral investigation of some impactites recovered by core drilling in the Manson impact structure. It was one of the largest known impact events to have happened in North America. Post-impact hydrothermal systems: Manson impact structure. 3, pp. B. 245-265. Bell, M. S., Reagan, M. K. Anderson, R. R. and Foster, C. T. Jr. 1996. B. The Pierre Shale, which is divided into identifiable sedimentary beds called members, also contains abundant fossils of numerous species of ammonites, ancestors of the chambered nautilus. The reworked assemblage decreases in abundance with increased distances from the Manson Impact Structure and the Sioux Ridge (a paleotopographic high). Abstracts of the 24th Lunar and Planetary Science Conference, pp. G. Brent Dalrymple, Radiometric Dating Does Work! Abstracts of the 23rd Lunar and Planetary Science Conference, pp. Jr. 1993. The State Hygienic Laboratory was one of several agencies called to respond to a well water incident in May in Calhoun County. The impact origin of each location listed on this website has been supported by unambiguous diagnostic evidence of hypervelocity impact that has been reported in a scientific (usually peer reviewed) context. Today the … pp. Science, v. 226, issue 4672, pp. 733-734. http://www.lpi.usra.edu/meetings/lpsc1991/pdf/1365.pdf. Koeberl, C., Anderson, R. R., Hartung, J. 4, pp. Buchanan, P. C., Koeberl, C. 1998. Anderson, R. R., Hartung, J. Geological Society of America Special Paper 302, pp. Rock samples were discovered to be unlike other rocks in the region. 145-219. doi: Koeberl, C. and Shirey, S. B. Grieve, R. A. F., and Cintala, M. J. 729-732. [Ruth Rice, 04/12/2007] Kunk, M. J., Snee, L. W., French, B. M., Harlan, S. S. and McGee, J. J. http://adsabs.harvard.edu/abs/1993Metic..28R.321B. Unlike many impact sites that are completely unknown to the people living within or above them, the town of Manson actually holds an annual Greater Crater Days festival with associated vendors, running events, and so on. B. and Anderson, R. R. 1988. Geological Society of America Special Paper 302, pp. Geological Society of America Special Paper 302, pp. Important information not only on the age (not K-T boundary age), but also on cratering mechanics and on the deposition of different types, was gained from the drill ing. 275-315. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19980018486.pdf, http://specialpapers.gsapubs.org/content/302/275.abstract. 1992. Kracher, A., Anderson, R. R. and Koeberl, C. 1994. 1994. B., 1993, Gravity investigation of the Manson impact structure, Iowa (abstract). Geological Society of America Special Paper 302, pp. Manson structure implicated. Crossey, L. J., and McCarville, P. 1993. The 1–3-m-thick Crow Creek Member is a unique marlstone with rip-up clasts and a basal coarse layer in the Upper Cretaceous Pierre Shale in South Dakota and Nebraska. 1565-1568. 2-3. https://archive.org/details/nasa_techdoc_19930000926, https://ia800306.us.archive.org/21/items/nasa_techdoc_19930000926/19930000926.pdf. a Dating Method:40Ar/39Ar method at 74.1 Ma (million years; Izett et al 1998). 40Ar/39Ar age of the Manson impact structure, Iowa, and correlative impact ejecta in the Crow Creek Member of the Pierre Shale (Upper Cretaceous), South Dakota and Nebraska. Mineralogical, petrological, and geochemical studies of drill core samples from the Manson impact structure, Iowa. B., Kunk, M. J. and Anderson, R. R. 1990. McCarville, P., 1994, Post-impact hydrothermal alteration of the Manson impact structure, Manson, Iowa. Iowa, USA. Thesis, The University of New Mexico, Albuquerque, New Mexico, 186 p. McHone, J F. and Dietz, R. S. (1992) Earth's multiple impact craters and astroblemes (abstract). The crater now sits approximately 200 feet below the City of Manson. The crater was named after the small town of Manson, Iowa, which lies near its center. Hartung, J. 771-772. http://www.lpi.usra.edu/meetings/lpsc1995/pdf/1386.pdf, Koeberl, C., Reimold, W. U., Kracher, A., Träxler, B., Vormaier, A. and Körner, W. 1996. The crater is not exposed on the surface, but has been thesubject of significant study through drilling. Science, Vol. 207-222. http://specialpapers.gsapubs.org/content/247/207.abstract. The area was known from unusual water well drill cuttings in 1912 of deformed rock, “crystalline clast breccia with a melt matrix” as a later report described it. Preliminary descriptions of impact rocks recovered by recent core drilling in the Manson impact structure (abstract). 1993. However, after 2.5 million years of weather and wear, the crater is now flat. Geological Society of America Abstracts with Programs, Vol. 1992. http://specialpapers.gsapubs.org/content/287/197.abstract. Abstacts of the 24th Lunar and Planetary Science Conference, pp. Gray marlstone clasts in the basal coarse layer have nannofossils derived from the underlying Gregory Member and Niobrara Chalk. The nonuniform geographic distribution of reworking suggests that Crow Creek deposition was linked to the Manson Impact. 1996. In the cornfields of the western part of the state, buried under 30 meters of glacial gravel, there is a 35-kilometer-wide crater called the Manson, Iowa Impact Structure. Finally, the inferred age of the shocked quartz, as determined from the age of the melted feldspar in the Manson impact structure (74.1 ± 0.1 Ma), is in very good agreement with the ages of the ash beds above and below it. History. 5823-5834..doi:10.1029/95JB03117, http://onlinelibrary.wiley.com/doi/10.1029/95JB03117/abstract, Keiswetter, D., Black, R. A. and Steeples, D. 1996. 4. pp. The Witzke, B. J. and Anderson, R. R., 1988, Iowa's Manson crater; the largest impact site in the U.S. Iowa Geology 1988, Iowa Department of Natural Resources, v. 13, pp. Manson, IA is located near the site of the Manson crater, formed by a meteorite collision that happened 74 million years ago. 23rd Lunar and Planetary Science Conference, pp. Evendence is shown where a meteorite landed 74 million years ago. 1994. At one time, it was thought to be the biggest impact by an object from outer space in North America. Many popular and scientific articles have been written on the location. Isotopic comparison of K/T boundary imapct glass with melt rock from the Chicxulub and Manson impact structures, Nature, v. 364, pp. Neodymium, strontium and oxygen isotope investigation of the target stratigraphy and impact melt rock from the Manson impact structure. Koeberl, C., Anderson, R. R., Boer, R. H., Blum, J. D., Chamberlain, C. P., Kracher, A., Reimold, W. U., Traxler B. and Vormaier A. 1994. 1993. Cisowski, S. M. 1988. Manson and company: Impact structures in the United States. The bedrock beneath Manson, Iowa, has been known as a region of unusual geology since 1912 when samples collected during the drilling of a town well at Manson proved to be unlike other rocks in the area. July 27, 2017 -- A meteorite that struck the earth 74 million years ago still has an effect on Iowa's water supply. Manson is located near the site of the Manson crater, formed by a meteorite collision that happened 74 million years ago. Re-Os isotope study of rocks from the Manson impact structure. The State Hygienic Laboratory was one of several agencies called to respond to a well water incident in May in Calhoun County. 1996. Bunte breccia-like deposits within the Manson impact structure (Iowa); evidence for impact into a shallow marine environment? The crater is buried 20 to 90 m below the surface. Geological Society of America Abstracts with Program (Annual Meeting), v. 26,  p. A-403.. In: Proceedings of the VIIth International Symposium on the Observation of the Continental Crust Through Drilling, Santa Fe, New Mexico, pp. Post-impact alteration of the Manson impact structure. Subsequent ice ages smoothed it over—erasing signs of a crater—but the impact obliterated the top layer of limestone that populated the rest of Iowa. B. 353. http://www.sciencemag.org/content/226/4672. MANSON, Iowa -- As "Armageddon" hits the big screen, it isn't going to make a deep impact among folks here: They already have their own extraterrestrial claim to fame in the form of a 24-mile-wide crater formed some 74 million years ago when a huge meteorite slammed into north-central Iowa and turned the region into a giant killing field. Geological Society of America Special Paper 302, pp. 485. http://adsabs.harvard.edu/full/1994Metic..29Q.485K, http://onlinelibrary.wiley.com/doi/10.1111/j.1945-5100.1994.tb00616.x/abstract, Kunk, M. J., Izett, G. A. and Sutter, J. F. 1987. Abstracts of the 1987 Fall Meeting of the American Geophysical Union, EOS Transactions. Manson is located near the site of the Manson crater, formed by a meteorite collision that happened 74 million years ago. 1211-1212. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1607.pdf, Schilling K. E., Anderson R. R., Peate D. W., Dorale J. Korotev, R. L., Rockow, K. M., Jolliff, B. L., Haskin, L. A., McCarville, P. and Crossey, L. J. A compilation of information and data on the Manson impact structure. However, this is not widely known as, during the last ice age, glaciers filled the crater in with dirt and debris, so that now the crater, and thus the town, are on the same level as the surrounding countryside. Post-impact hydrothermal alteration of the Manson impact structure. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 132, pp. Geological Society of America Special Paper 302, pp. There are many craters documented on this site. 719-720. http://www.lpi.usra.edu/meetings/lpsc1994/pdf/1360.pdf. The crater, measuring more than 23 miles in diameter, was created when a meteorite crashed into earth some 74 million years ago. 25-46., http://www.sciencedirect.com/science/article/pii/S003101829700045X, Korotev, R. L., Jolliff, B. L., Rockow, K. M., Haskin, L. A. and Crossey, L. J. Preliminary results of the U.S.Geological Survey - Iowa Department of Natural Resources Geological Survey Bureau Manson Core Drilling Project. Although the crater is not visible today, the impact of the meteor significantly changed the … 245-265. doi: 10.1130/0-8137-2302-7.245, http://specialpapers.gsapubs.org/content/302/245.abstract. 1567-1568. http://www.lpi.usra.edu/meetings/lpsc1993/pdf/1785.pdf, Zeitler, P., 1996, 40Ar/39Ar thermochronology of shocked feldspars from the Manson impact structure. 397-417. doi: 10.1130/0-8137-2302-7.397, http://specialpapers.gsapubs.org/content/302/397.abstract. The crater is not exposed on the surface, but has been the. 1998. 781-782. http://adsabs.harvard.edu/full/1993LPI....24..781K, Koeberl, C. and Anderson, R. R. 1996. 188-189. http://www.lpi.usra.edu/meetings/lpsc1988/pdf/1096.pdf. The unusual geology of the land surrounding the Manson structure was discovered in 1912, when a town water well was drilled. During the course of this investigation 12 research cores, totaling over 1.2 km of core, were obtained from all terranes of the crater. Journal of Geophysical Research, v. 101, issue B3, pp. Abstracts of the 17th Lunar and Planetary Science Conference, pp. 12, pp. Unfortunately, this impact crater is very old by human standards, since it occurred nearly 75 million years ago. 325-330. doi: 10.1130/0-8137-2302-7.325, http://specialpapers.gsapubs.org/content/302/325.abstract, Pisarik, R., Petershagen, J., Wilke, K. and Sendlein,L.V.A., 1977, Magnetic studies of the Manson disturbed area (abstract). 127-134. doi:10.1016/j.cretres.2008.06.005, http://www.sciencedirect.com/science/article/pii/S0195667108000827, Varricchio D. J., Koeberl C., Raven R. F. Wolbach W. S., Elsik W. C., and Miggins D. P., 2010, Tracing the Manson impact event across the Western Interior Cretaceous Seaway, Geological Society of America Special Paper 465, pp. nderson, R. R., Witzke, B. J. Evendence is shown where a meteorite landed 74 million years ago. Mineralogical, petrological, and geochemical studies of drill core samples from the Manson impact structure, Iowa. Manson impact structure rocks: Geochemistry of impactites (abstract). Anderson, R. R., Hartung, J.B., Witzke, B.J., Shoemaker, E.M. and Roddy,D.J. Abstracts of the 22nd Lunar and Planetary Science Conference, pp. Geological Society of America Special Paper 302, pp. Preliminary 40Ar/39Ar age spectrum and laser probe dating of the M1 core of the Manson impact structure, Iowa: A K-T boundary crater candidate (abstract). Post-impact hydrothermal systems: Manson impact structure, Manson, Iowa (abstract). Preliminary investigation of shocked grains (Manson ejecta? Geological Society of America Special Paper 302, pp. Try pasting the link shown into a search engine or searching for the article authors, title, or other reference information. Postimpact hydrothermal alteration of the Manson impact structure (abstract). Geological Society of America Abstracts with Program (Annual Meeting), v. 25, p. A222.. Although the lab is regularly called upon to perform well water testing, the area where the incident occurred made the case unusual, said Terry Cain, …