noaa-other-13298 Dare County, North Carolina Quaternary Subsurface Aminostratigraphy Riggs, S.R.; York, L.L.; Wehmiller, J.F.; Snyder, S.W. Dare County, North Carolina Quaternary Subsurface Aminostratigraphy 2012-07-27 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/13298 Investigator S.R. Riggs Investigator L.L. York Investigator J.F. Wehmiller Investigator S.W. Snyder earth science paleoclimate others geoscientificInformation 1000000 cal yr BP 0 cal yr BP Complete 35.865 35.865 -75.858 -75.858 Continent North America United States Of America North Carolina Stetson Pit>LATITUDE 35.865>LONGITUDE -75.858 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Riggs, S.R., L.L. York, J.F. Wehmiller, and S.W. Snyder. 1992. Depositional patterns resulting from high-frequency Quaternary sea-level fluctuations in northeastern North Carolina. In: Fletcher, C. H. III and Wehmiller, J. F. (Eds.). Quaternary Coasts of the United States: Marine and Lacustrine Systems. Society of Economic Paleontologists and Mineralogists Special Publication 48, p. 155-160.

Amino acid enantiomeric ratio data are presented for Pleistocene mollusks obtained from a suite of split-spoon and vibracore samples at sites in Dare County, northeastern North Carolina. The region lies within the Albemarle Embayment, a thick sequence of Quaternary and pre-Quaternary strata in the mid-Atlantic coastal plain, eastern United States. Land surface elevations range from 0 to +2 m. Sample depths range from ~ 4 meters to ~ 35 m below mean sea level. Specimens of the bivalve mollusk Mulinia and Mercenaria have been analyzed by ion-exchange and gas chromatography. Aminozones representing clusters of D/L values are used to correlate depositional sequences in the study area and to estimate times of deposition based on kinetic modeling of amino acid racemization. Deepest units are estimated to be older than 1 million years, while the shallowest Pleistocene units are estimated to be last interglacial (~80,000 - 125,000 yrs) in age, based on both racemization and uranium-thorium age estimates. STUDY NOTES: Extent of Racemization (D/L) data for mollusks from Pleistocene coastal units, subsurface sections of the Atlantic Coastal Plain, Dare County, North Carolina. Samples collected by L.L. York, S.R. Riggs, W. Miller III, and T.M. Cronin. Samples collected in 1970's and 1980's by vibracoring, excavation (Stetson Pit), and split-spoon drilling (Stetson Pit). Samples prepared and analyzed at the University of Delaware, Newark DE. [UDEL]. Lab PI John F. Wehmiller. Pretreatment: Fragments cut from shell valves; surface cleaning with dental tools; dilute HCl and distilled water wash; air dry AA fraction="amino fraction" THAA = total hydrolyzable amino acids; FAA = free amino acids (zero hydrolysis time) Hydrolysis procedure: 6N HCl 22 hours 105 deg C (for THAA only) Bleach: No Instrumental programming: GC temperature program; HPLC buffer gradient Blank corrections: no Response factors: no Lab Code UDEL= University of Delaware Sample ID = identity of specific shell analyzed Analytical method: GC = gas chromatography, used for multiple amino acids; Ion-exchange High Pressure Liquid Chromatography used for determination of A/I values (HPLC) Subsample ID = usually the same as sample ID; repeat fragments of same shell will have unique identification Ratio type = (peak area or peak height ratios) D/L values are reported as the means of multiple chromatograms, usually at least 2. For GC results, in most cases sample derivatives were analyzed using more than one GC column. Samples selected for analysis were chosen because they appeared to be the most robust specimens among those available. In most cases, samples were not whole valves. Abraded, rounded, or chalky fragments were avoided where possible, and multiple shells from each collection were analyzed in almost all cases. No data screening procedures have been applied. No interlab sample comparisons were made during the period of these analyses. Information on sample quality (fragment, whole shell, abraded, chalky, etc. will be compiled for a future version of this datafile. Abbreviations: A/I D-alloisoleucine/L-isoleucine Ala Alanine Asx Aspartic acid and asparagine Glx Glutamic acid and glutamine Leu Leucine Phe Phenylalanine Pro Proline Val Valine 9999 = no data available for this amino acid in this sample UDAMS LOCALITY DESIGNATIONS (UDAMS = UDAMinoStratigraphy) 07002 Excavation in 1981-1982 (W. Miller to T. M. Cronin to J. Wehmiler) Surface elevation ~ 2m 07004 Excavation in 1981-1982 (W. Miller to T. M. Cronin to J. Wehmiler) Surface elevation ~ 2m 07005 Core taken in 1982 (Miller, 1982). Top of core at ~ 0 m elevation 07077 Core taken in 1982 (Miller, 1982). Top of core at ~ 0 m elevation 07127 Core taken in 1982 (Miller, 1982). Top of core at ~ 0 m elevation 07128 Samples from original excavation in early 1980's.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/aar/riggs1992dare/riggs1992dare.txt GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/aar/riggs1992dare/riggs1992dare.xls USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11