Pre-Illinoian Stage

Pre-Illinoian Stage

The Pre-Illinoian Stage is the name currently used for early and middle Pleistocene glacial and interglacial deposits within North America. As the oldest stage in the North American nomenclature, it precedes the Illinoian Stage.Hallberg, G.R., 1986, "Pre-Wisconsin glacial stratigraphy of the Central Plains region in Iowa, Nebraska, Kansas, and Missouri", Quaternary Science Reviews. vol. 5, pp. 11-15.] Richmond, G.M. and D.S. Fullerton, 1986, "Summation of Quaternary glaciations in the United States of America", Quaternary Science Reviews. vol. 5, pp. 183-196.] During the Pre-Illinoian Stage, 11 distinct glacial period have been recognized. In the British Isles, the Pre-Illinoian Stage is equivalent to the Bramertonian, Pre-Pastonian, Pastonian, Beestonian, Cromerian, Anglian, Hoxnian, and lowermost Wolstonian stages combined.Gibbard, P.L., S. Boreham, K.M. Cohen and A. Moscariello, 2007, [http://www.quaternary.stratigraphy.org.uk/correlation/POSTERSTRAT_v2007b_small.jpg"Global chronostratigraphical correlation table for the last 2.7 million years v. 2007b"] , jpg version 844 KB. Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England] The end of Marine Isotope Stage 9 is the end of the Pre-Illinoian Stage. Thus, the Pre-illinoian Stage ranges from the beginning of the Pleistocene until 300,000 years ago.Lisiecki, L.E., 2005, [http://www.lorraine-lisiecki.com/LR04_MISboundaries.txt "Ages of MIS boundaries."] [http://www.lorraine-lisiecki.com/stack.html LR04 Benthic Stack] Boston University, Boston, MA] Lisiecki, L.E., and M.E. Raymo, 2005, "A Pliocene-Pleistocene stack of 57 globally distributed benthic d18O records." Paleoceanography. vol. 20, PA1003, doi:10.1029/2004PA001071]

The Pleistocene prior to the Illinoian Stage had previously been subdivided into the Nebraskian (glacial), Aftonian (interglacial), Kansan (glacial), and Yarmouth (interglacial) stages (periods).Flint, R.F., 1957, "Glacial Geology and the Pleistocene Epoch." John Wiley & Sons, New York. 553 p. New York] However, detailed studies of these stages revealed that the assumptions and criteria, on which they were defined, proved to be wrong to the point that these stages became meaningless in terms of the actual glacial - interglacial record.Dort, W., Jr., 1966, "Nebraskan and Kansan Stades: Complexity and Importance." Science. vol. 154, no. 3750, pp. 771-772. DOI: 10.1126/science.154.3750.771] Boellstorff, J., 1978a, "Chronology of some Late Cenozoic deposits from the central United States and the Ice Ages. " Transactions of the Nebraska Academy of Science. vol 6, pp. 35–49] Boellstorff, J., 1978b, North American Pleistocene stages reconsidered in the light of probable Pliocene-Pleistocene continental glaciation." Science. vol. 202, pp. 305–307.] For example, instead of 2 glaciations having occurred prior to the Illinoian Stage, it was found that 11 distinct glaciations had occurred. In addition, what was presumed to be a single volcanic ash bed, which was used to correlate and differentiate between Kansan and Nebraskan glacial deposits, was found to actually be three volcanic ash beds of greatly differing ages. Similarly, paleosols used in the definition of the stages were found to have been greatly miscorrelated and consist of paleosols of greatly differing ages. Because of these and other major problems, the concepts, on which the Nebraskian, Aftonian, Kansan, and Yarmouth stages are defined, were discredited and these stages were discarded as unusable by North American geologists. As a result, these stages were merged into the Pre-Illinoian Stage.Roy, M., P.U. Clark, R.W. Barendregt, J.R., Glasmann, and R.J. Enkin, 2004, [http://geo.oregonstate.edu/people/faculty/publications/clarkp/Royetal-GSAB-2004.pdf "Glacial stratigraphy and paleomagnetism of late Cenozoic deposits of the north-central United States"] , PDF version, 1.2 MB. Geological Society of America Bulletin. vol. 116, no. 1-2; pp. 30-41; DOI: 10.1130/B25325.1]

References

External Links

*Aber, J.S., 2006, [http://academic.emporia.edu/aberjame/ice/lec17/lec17.htm "Regional Glaciation of Kansas and Nebraska"] , Emporia State University, Emporia, Kansas.
*anonymous, 1997, [http://www.emporia.edu/earthsci/gage/pre-wisc/gmap0.htm "Glacial Map of North-Central United States"] , Work Group on Geospatial Analysis of Glaciated Environments (GAGE), INQUA Commission on Glaciation, Emporia State University, Emporia, Kansas.
*anonymous, 2000, [http://www.emporia.edu/earthsci/gage/pre-wisc/pre-wisc.htm "Pre-Wisconsin Glaciation of Central North America"] , Work Group on Geospatial Analysis of Glaciated Environments (GAGE), INQUA Commission on Glaciation, Emporia State University, Emporia, Kansas.
*anonymous, 2007, [http://www.quaternary.stratigraphy.org.uk/correlation/chart.html "Global correlation tables for the Quaternary"] , Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England
*Hallberg, G.R., ed., 1980a, [http://gsbdata.igsb.uiowa.edu/gsbpubs/pdf/TIS-10.pdf "Pleistocene stratigraphy in east-central Iowa"] , PDF version 15.6 MB. Technical information Series. no. 10. Iowa Geological Survey Bureau, Ames, IA.
*Hallberg, G. R., ed., 1980b, [http://gsbdata.igsb.uiowa.edu/gsbpubs/pdf/TIS-11.pdf "Illinoian and Pre-Illinoian stratigraphy of southeast Iowa and adjacent Illinois"] , PDF version 19.3 MB. Technical information Series. no. 11. Iowa Geological Survey Bureau, Ames, IA.
*Hallberg, G. R., T. E. Fenton, T. J. Kemmis, and G. A. 
Miller, 1980, [http://www.igsb.uiowa.edu/gsbpubs/pdf/GB-03.pdf "Yarmouth Revisited: Midwest Friends of 
the Pleistocene 27th Field Conference."] , PDF version 4.6 MB. Guidebook no. 3. 
Iowa Geological Survey Bureau, Ames, IA.

Further reading

*Ehlers, J., and P.L. Gibbard, 2004a, "Quaternary Glaciations: Extent and Chronology 2: Part II North America", Elsevier, Amsterdam. ISBN 0-444-51462-7
*Gillespie, A.R., S.C. Porter, and B.F. Atwater, 2004, "The Quaternary Period in the United States. " Developments in Quaternary Science no. 1. Elsevier, Amsterdam. ISBN 978-0-444-51471-4
*Mangerud, J., J. Ehlers, and P. Gibbard, 2004, "Quaternary Glaciations: Extent and Chronology 1: Part I Europe", Elsevier, Amsterdam. ISBN 0-444-51462-7
*Sibrava, V., Bowen, D.Q, and Richmond, G.M., eds., 1986, "Quaternary Glaciations in the Northern Hemisphere, Quaternary Science Reviews", vol. 5, pp. 1-514.

ee also

*Ice age
*Glacial period
*Last glacial period
*Timeline of glaciation


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Pre-Pastonian Stage — The Pre Pastonian Stage or Baventian Stage, is the name for an early Pleistocene stage used in the British Isles. It precedes the Pastonian Stage and follows the Bramertonian Stage. This stage ended 1.806 Ma (million years ago) at the end of… …   Wikipedia

  • Pre-Illinoian — The Pre Illinoian Stage is often synonymous with Pre Illinoian glacial[1][2] and used by Quaternary geologists for the early and middle Pleistocene glacial and interglacial periods of geologic time in North America from 2.5 Ma 500,000 years ago,… …   Wikipedia

  • Illinoian Stage — The Illinoian Stage is the name used by Quaternary geologists in North America to designate middle Pleistocene glacial and interglacial deposits. It precedes the Wisconsin Stage and follows the Pre Illinoian Stage in North America. The Illinoian… …   Wikipedia

  • Hoxnian Stage — The Hoxnian Stage is a middle Pleistocene stage of the geological history of the British Isles. It precedes the Wolstonian Stage and follows the Anglian Stage. The Hoxnian Stage corresponds to the Holstein Interglacial (or Stage ) in northern… …   Wikipedia

  • Wolstonian Stage — The Wolstonian interglacial is the former name for a middle Pleistocene stage that is now known as the Wolstonian Stage in the British Isles. It precedes the Ipswichian Stage (Eemian Stage in Europe) and follows the Hoxnian Stage in the British… …   Wikipedia

  • Cromerian Stage — The Cromerian Stage is the name for a middle Pleistocene stage used in the in the British Isles that is known as the Cromerian Complex in Europe. It precedes the Anglian Stage and follows the Beestonian Stage in the British Iles. The Cromerian… …   Wikipedia

  • Beestonian stage — The Beestonian Stage is the name for an early Pleistocene stage used in the British Isles. It precedes the Cromerian Stage and follows the Pastonian Stage. This stage consists of alternating glacial and interglacial phases instead of being a… …   Wikipedia

  • Anglian Stage — The Anglian Satge is the name for a middle Pleistocene stage used in the British Isles. It precedes the Hoxnian Stage and follows the Cromerian Stage in the British Isles. The Anglian Stage is equivalent to the Elsterian Stage of Europe and… …   Wikipedia

  • Anglian (stage) — The Anglian Stage is the name for a middle Pleistocene stage used in the British Isles. It precedes the Hoxnian Stage and follows the Cromerian Stage in the British Isles. The Anglian Stage is equivalent to the Elsterian Stage of northern… …   Wikipedia

  • Pastonian Stage — The Pastonian interglacial, now called the Pastonian Stage, is the name for an early Pleistocene stage used in the British Isles. It precedes the Beestonian Stage and follows the Pre Pastonian Stage. This stage started 1.816 Ma (million years… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”