GISP2 Ice Core and Source Region MIS2 Mineralogy and Isotope Chemistry Biscaye, P.E.; Grousset, F.E.; Revel, M.; Van der Gaast, S.; Zielinski, G.A.; Vaars, A.; Kukla, G. Biscaye, P.E. Grousset, F.E. Revel, M. Van der Gaast, S. Zielinski, G.A. Vaars, A. Kukla, G. earth science/paleoclimate/ice cores (calcium,particles,null,parts per billion,null,ice cores,null,x-ray diffraction,N,null) earth science/paleoclimate/ice cores (143Nd/144Nd,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,epsilon Nd units) earth science/paleoclimate/ice cores (208Pb/204Pb,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (depth at sample start,null,null,meter,null,ice cores,null,null,N,null) earth science/paleoclimate/ice cores (208Pb/206Pb,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (depth at sample end,null,null,meter,null,ice cores,null,null,N,null) earth science/paleoclimate/ice cores (mineral index,particles,null,milligram per kilogram,null,ice cores,null,x-ray diffraction,N,aluminum silicates) earth science/paleoclimate/ice cores (grain size mean,particles,null,millimeter,null,ice cores,null,electric sensing particle size analysis,N,null) earth science/paleoclimate/ice cores (chlorite,particles,null,percent,null,ice cores,null,x-ray diffraction,N,null) earth science/paleoclimate/ice cores (143Nd/144Nd,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (206Pb/207Pb,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (epsilon neodymium,particles,null,epsilon unit,null,ice cores,null,thermal ionization mass spectrometry,N,epsilon Nd units) earth science/paleoclimate/ice cores (sample identification,null,null,null,null,ice cores,null,null,C,null) earth science/paleoclimate/ice cores (illite,particles,null,percent,null,ice cores,null,x-ray diffraction,N,null) earth science/paleoclimate/ice cores (kaolinite,particles,null,percent,null,ice cores,null,x-ray diffraction,N,null) earth science/paleoclimate/ice cores (smectite,particles,null,percent,null,ice cores,null,x-ray diffraction,N,null) earth science/paleoclimate/ice cores (207Pb/204Pb,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (mineral index,particles,null,milligram per square centimeter per kiloyear,null,ice cores,null,x-ray diffraction,N,aluminum silicates) earth science/paleoclimate/ice cores (87Sr/86Sr,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (epsilon neodymium,particles,null,epsilon unit,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (ice age at sample end,null,null,calendar year before present,null,ice cores,null,null,N,null) earth science/paleoclimate/ice cores (206Pb/204Pb,particles,null,dimensionless,null,ice cores,null,thermal ionization mass spectrometry,N,null) earth science/paleoclimate/ice cores (grain size beta,particles,null,dimensionless,null,ice cores,null,electric sensing particle size analysis,N,null) earth science/paleoclimate/ice cores (ice age at sample start,null,null,calendar year before present,null,ice cores,null,null,N,null) earth science/paleoclimate/ice core (GISP2>LATITUDE 72.6>LONGITUDE -38.5) Samples of dust from the Greenland Ice Sheet Project 2 (GISP2) ice core, Summit, Greenland, dated within marine isotope stage 2 (between 23,340 and 26,180 calendar years B.P.) around the time of the coldest, local, last glacial temperatures, have been analyzed to determine their provenance. To accomplish this, we have compared them with approximately Coeval aeolian sediments (mostly loesses) sampled in possible source areas (PSAs) from around the northern hemisphere. The <5-um grain-size fraction of these samples was analyzed on the basis that it corresponds to the atmospheric dust component of that time and locale, which was sufficiently fine grained to be transported over long distances. On the basis of comparison of the clay mineralogy and Sr, Nd and Pb isotope composition with ice dust and PSAs and assuming that we have sampled the most important PSAs, we have determined that the probable source area of these GISP2 dusts was in eastern Asia. The dust was not derived from either the midcontinental United States or the Sahara, two more proximal areas that have been suggested as potential sources based on atmospheric circulation modeling. Except for a brief period during an interstadial, when dust transport was exceptionally low (for glacial times) and had a mineralogical composition indicative of a slightly more southern provenance, the source area of the dust did not change significantly during times of variably higher fluxes of dust with larger mean grain size or lower fluxes of dust with smaller mean grain size. This includes the high-dust period that correlates with the Heinrich 2 period of major iceberg discharge into the North Atlantic. Variable wind strengths must therefore be invoked to account for these abrupt and significant changes in dust flux and grain size. STUDY NOTES: Clay mineralogy, Nd/Sm and Pb isotope data from the GISP2 ice core within marine isotope stage 2 (between 23,340 and 26,180 calendar years B.P.), plus same parameters measured on samples from possible source regions for GISP2 dust. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Biscaye, P.E. Investigator : Grousset, F.E. Investigator : Revel, M. Investigator : Van der Gaast, S. Investigator : Zielinski, G.A. Investigator : Vaars, A. Investigator : Kukla, G. 1997-11-30 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/17815 https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/srcmin.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/gisp2min.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/srcmin.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/gisp2min.txt English https://www.ncdc.noaa.gov/paleo/study/17815 https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/srcmin.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/gisp2min.txt P. E. Biscaye, F. E. Grousset, M. Revel, S. Van der Gaast, G. A. Zielinski, A. Vaars, G. Kukla1997Asian provenance of glacial dust (stage 2) in the Greenland Ice Sheet Project 2 Ice Core, Summit, GreenlandJournal of Geophysical Research: Oceans102C1226765-2678110.1029/97JC01249http://onlinelibrary.wiley.com/enhanced/doi/10.1029/97JC01249/ START YEAR: 26200 cal yr BP * END YEAR: 23315 cal yr BP -38.5 72.6 -38.5 72.6