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Hartung, J. B., Kunk, M.J. and
Anderson, R.R., Geology, geophysics, and geochronology of the Manson impact structure. Global Catastrophes in Earth History, Geological Society of America, Special Paper 247, pp. 207-221.
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In 1991 and 1992 the U.S. Geological Survey along with others including the Iowa
Geological Survey conducted detailed research in part to test the possible connection of the Manson impact structure with the
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and extends under portions of three adjoining counties. That an anomalous structure underlaid the area was known from unusual water well drill cuttings in 1912 of deformed rock, "crystalline
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with a melt matrix" as a later report described it. A research investigation was started in 1955, and it was labeled a "cryptovolcanic structure" (a hypothetical
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285:. It was one of the largest known impact events to have happened in North America. Previously it was thought to have led to the extinction of the
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isotope ratio dating of the core from the impact structure gave an age of about 74 Ma, or about 10 Ma older than the K–T boundary.
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483:"The Manson impact was the biggest thing that has ever occurred on the mainland United States. Of any type. Ever," Bill Bryson,
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544:"The Manson Impact Structure: 40Ar/39Ar Age and Its Distal Impact Ejecta in the Pierre Shale in Southeastern South Dakota"
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were instantaneously vaporized down to the basement rocks, giving Manson the anomalous soft water that it has today.
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about 2 km (1.2 mi) in diameter. The site at the time was the shore of a shallow inland sea, the
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Planetary and Space
Science Centre University of New Brunswick Fredericton
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Detailed illustrated time sequence of the Manson impact event from NASA
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Izett, G. A.; Cobban, W. A.; Obradovich, J. D.; Kunk, M. J. (1993).
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No surface evidence exists due to comparatively recent coverage by
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The Manson Impact
Structure, Iowa: Anatomy of an Impact Crater
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steam explosion). Further investigation was undertaken by
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Manson impact location shown in red on bedrock map of Iowa
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Location of the impact structure in Iowa, United States
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Christian
Koeberl and Raymond R. Anderson, eds; 1996,
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649:Additional material from Iowa DNR with image links
666:Aerial Exploration of the Manson Impact Structure
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289:until isotopic ages proved that it was too old.
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325:who proposed an impact origin in 1959 and by
27:74 million year old impact structure in Iowa
436:who studied impact craters, in Manson, Iowa
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374:The impactor is considered to have been a
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343:Cretaceous–Paleogene extinction event
301:Extent of the Manson impact structure
1282:Landforms of Pocahontas County, Iowa
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485:A Short History of Nearly Everything
1257:Impact craters of the United States
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418:layers that give the rest of Iowa
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281:Period, approximately 74
243:Manson impact structure (Iowa)
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1224:Lunar and Planetary Institute
1056:Cretaceous–Paleogene boundary
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218:Show map of the United States
568:10.1126/science.262.5134.729
277:struck the Earth during the
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1116:Planar deformation features
640:Raymond R. Anderson, 1999,
333:grains which confirmed the
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1219:Impact Field Studies Group
532:Koeberl and Anderson 1996.
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1262:Cretaceous impact craters
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1267:Cretaceous United States
1189:William Kenneth Hartmann
855:Clearwater East and West
803:Confirmed≥20 km diameter
1106:Ordovician meteor event
382:. The impact disrupted
380:Western Interior Seaway
259:Manson impact structure
72:35 km (22 mi)
56:Impact crater/structure
39:Manson impact structure
1209:Eugene Merle Shoemaker
1086:Late Heavy Bombardment
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1252:Earth Impact Database
1230:Traces of Catastrophe
1214:Earth Impact Database
1162:Ralph Belknap Baldwin
460:Earth Impact Database
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398:basement as well as
560:1993Sci...262..729I
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1126:Shock metamorphism
1031:Alvarez hypothesis
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337:of the structure.
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1179:Edward C. T. Chao
554:(5134): 729–732.
311:Pocahontas County
265:near the site of
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148:42.583°N 94.550°W
16:(Redirected from
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1204:Peter H. Schultz
1167:Daniel Barringer
1076:Impact structure
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1172:Barringer Medal
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18:Manson crater
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1199:Graham Ryder
1121:Shatter cone
1111:Philippinite
960:Saint Martin
955:Rochechouart
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860:Gosses Bluff
815:Amelia Creek
718:Impact event
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613:Bibliography
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506:. Retrieved
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468:. Retrieved
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373:
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307:glacial till
304:
267:Manson, Iowa
258:
256:
184:Municipality
32:Iowa geology
995:Tookoonooka
980:Steen River
970:Siljan Ring
900:Manicouagan
885:Keurusselkä
508:17 February
503:Yahoo! News
400:sedimentary
396:Precambrian
293:Description
151: /
126:Coordinates
1246:Categories
1136:Stishovite
1036:Australite
1015:Yarrabubba
985:Strangways
945:Presqu'île
920:Montagnais
890:Lappajärvi
840:Charlevoix
825:Beaverhead
820:Araguainha
774:By country
744:Antarctica
644:, Iowa DNR
470:2017-10-09
441:References
420:hard water
412:Cretaceous
279:Cretaceous
61:Confidence
1101:Moldavite
1096:Meteorite
1081:Impactite
1010:Woodleigh
1005:Vredefort
965:Shoemaker
925:Morokweng
910:Mistastin
850:Chicxulub
754:Australia
734:Worldwide
487:2003:238.
416:Limestone
404:Paleozoic
287:dinosaurs
269:where an
114:Chondrite
64:Confirmed
1155:Research
1000:Tunnunik
895:Logancha
865:Haughton
835:Carswell
779:Possible
584:42594905
576:17812340
455:"Manson"
410:through
408:Devonian
319:volcanic
271:asteroid
120:Location
69:Diameter
1146:Tektite
1141:Suevite
1046:Coesite
1041:Breccia
990:Sudbury
940:Popigai
935:Obolon'
915:Mjølnir
880:Karakul
870:Kamensk
830:Boltysh
810:Acraman
556:Bibcode
548:Science
394:of the
384:granite
164:Country
139:94°33′W
136:42°35′N
99:Drilled
91:Exposed
1024:Topics
905:Manson
759:Europe
739:Africa
626:
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392:shales
390:, and
388:gneiss
345:. The
261:is an
188:Manson
108:Bolide
727:Lists
580:S2CID
523:1990.
406:age,
174:State
875:Kara
624:ISBN
572:PMID
510:2012
257:The
178:Iowa
110:type
564:doi
552:262
273:or
102:Yes
78:Age
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368:Ar
355:Ar
283:Ma
94:No
694:e
687:t
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358:/
20:)
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