Illinois River Valley Last Glacial Loess Data Nash, T.A.; Conroy, J.L.; Grimley, D.A.; Guenthner, W.R.; Curry, B.B. Nash, T.A. Conroy, J.L. Grimley, D.A. Guenthner, W.R. Curry, B.B. Last Glacial Maximum earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Columella alticola; number of whole shells) earth science/paleoclimate/loess (depth,null,null,centimeter,null,loess,null,null,N,null) earth science/paleoclimate/loess (illite,loess,null,percent,null,loess,null,null,N,null) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Stenotrema hirsutum; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Webbhelix multilineata; number of whole shells) earth science/paleoclimate/loess (depth,null,null,centimeter,null,loess,null,null,N,Height above Roxana Silt) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Anguispira alternata; number of whole shells) earth science/paleoclimate/loess (age,null,null,calendar year before present,null,loess,null,null,N,null) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Succinea sp.; number of whole shells) earth science/paleoclimate/loess (total gastropods,null,null,count,null,loess,null,null,N,Total Gastropod shells; number of whole shells) earth science/paleoclimate/loess (mass magnetic susceptibility,loess,null,cubic meter per kilogram,null,loess,null,null,N,units are 10^-8 m^3 kg^-1) earth science/paleoclimate/loess (delta 13C,gastropod,null,per mil VPDB,null,loess,null,isotope ratio mass spectrometry,N,Succinea sp.) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Vertigo hubrichti; number of whole shells) earth science/paleoclimate/loess (grain size class,loess,null,dimensionless,null,loess,null,null,N,(coarse+medium silt)/(clay+v fine silt+fine silt)) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Discus whitneyi; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Vertigo modesta; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Vertigo elatior; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Carychium exile; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Punctum minutissium; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Euconulus fulvus; number of whole shells) earth science/paleoclimate/loess (delta 18O,gastropod,null,per mil VPDB,null,loess,null,isotope ratio mass spectrometry,N,Succinea sp.) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Stenotrema leai; number of whole shells) earth science/paleoclimate/loess (mineral index,loess,null,percent,null,loess,null,null,N,expandable clays) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Zonitoides arboreus; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Nesovitrea electrina; number of whole shells) earth science/paleoclimate/loess (identified gastropod,null,null,count,null,loess,null,null,N,Hendersonia occulta; number of whole shells) earth science/paleoclimate/loess (Thomas Quarry>LATITUDE 39.5201>LONGITUDE -90.5157) (New Cottonwood School>LATITUDE 40.0236>LONGITUDE -90.2905) The chronology and cause of millennial depositional oscillations within last glacial loess of the Central Lowlands of the United States are uncertain. Here, we present a new age model that indicates the Peoria Silt along the Illinois River Valley accumulated episodically from ~28,500 to 16,000 cal yr BP, as the Lake Michigan Lobe margin fluctuated within northeastern Illinois. The age model indicates accelerated loess deposition coincident with regional glacial advances during the local last glacial maximum. A weakly developed paleosol, the Jules Geosol, represents a period of significantly slower deposition, from 23,700 to 22,000 cal yr BP. A gastropod assemblage-based reconstruction of mean July temperature shows temperatures 6-10C cooler than modern during Peoria Silt deposition. Stable oxygen and carbon isotope values (d18O and d13C) of gastropod carbonate do not vary significantly across the pedostratigraphic boundary of the Jules Geosol, suggesting slower loess accumulation was a result of reduced glacial sediment supply rather than direct climatic factors. However, a decrease in d18O values occurred between 26,000 and 24,000 cal yr BP, synchronous with the Lake Michigan Lobe's southernmost advance. This d18O decrease suggests a coupling of regional summer hydroclimate and ice lobe position during the late glacial period. STUDY NOTES: Physical properties (grain size and magnetic susceptibility), stable isotope (d13C and d18O), and gastropod assemblage data from late-glacial (~28-20 kyrbp) loess deposits at 2 locations (New Cottonwood School and Thomas Quarry) in the Illinois River Valley. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Nash, T.A. Investigator : Conroy, J.L. Investigator : Grimley, D.A. Investigator : Guenthner, W.R. Investigator : Curry, B.B. 2017-09-28 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/22693 https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017clay.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017ms.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017ms.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017clay.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017ms.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017ms.txt English https://www.ncdc.noaa.gov/paleo/study/22693 https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017gast.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017clay.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/thomas2017ms.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/loess/peoria/newcottonwood2017ms.txt Thomas A. Nash, Jessica L. Conroy, David A. Grimley, William R. Guenthner, Ben Brandon Curry 2017Episodic deposition of Illinois Valley Peoria silt in association with Lake Michigan Lobe fluctuations during the last glacial maximumQuaternary Research10.1017/qua.2017.66https://www.cambridge.org/core/journals/quaternary-research/article/episodic-deposition-of-illinois-valley-peoria-silt-in-association-with-lake-michigan-lobe-fluctuations-during-the-last-glacial-maximum/16D885A9FDFA31CD563E556C352854EE START YEAR: 27818 cal yr BP * END YEAR: 20464 cal yr BP -90.5157 39.5201 -90.2905 40.0236