noaa-other-27070 Northern Spain 23,000 Year Littorina littorea Amino Acid Racemization Data Ortiz, J.E.; Sanchez-Palencia, Y.; Gutierrez-Zugasti, I.; Torres, T.; Gonzalez-Morales, M. Northern Spain 23,000 Year Littorina littorea Amino Acid Racemization Data 2019-06-17 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/27070 Investigator J.E. Ortiz Investigator Y. Sanchez-Palencia Investigator I. Gutierrez-Zugasti Investigator T. Torres Investigator M. Gonzalez-Morales earth science paleoclimate others geoscientificInformation 23000 cal yr BP 0 cal yr BP Complete 43.3 43.5 -5.1 -3.4 Continent Europe Southern Europe Spain Northern Spain caves>LATITUDE >LONGITUDE 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

325 Broadway, E/NE31

Boulder CO 80305-3328 USA online ASCII Jose E. Ortiz, Yolanda Sanchez-Palencia, Igor Gutierrez-Zugasti, Trinidad Torres, Manuel Gonzalez-Morales 2018 Quaternary Geochronology 46 16-27 10.1016/j.quageo.2018.02.002 https://www.sciencedirect.com/science/article/pii/S1871101417300663

The inter-and intra-crystalline fractions of the topshell Phorcus lineatus recovered from modern specimens and shells from archaeological sites in Northern Spain covering Neolithic, Mesolithic, and Upper Magdalenian periods were examined for amino acid composition and racemisation over time. The main loss of proteins from the inter-crystalline fraction occurred within the first 6000 years after the death of the organism. In contrast, the intra-crystalline fraction isolated by bleaching-with a different protein composition to that of the inter-crystalline fraction-appeared to behave like a closed system for at least 12.6 ka, as reflected by the lack of a significant decrease in amino acid content. However, changes in the relative composition of the amino acids present in these shells occurred during this period. The concentration of aspartic acid remained almost constant with age within the intra-crystalline fraction and its contribution to the total amino acid content also remained the same. Good correspondence was obtained between Asx D/L values in unbleached and bleached samples and age, thereby allowing the dating of archaeological sites and the determination of chronometric age. STUDY NOTES: Amino acid racemization (AAR) data in mollusc samples (Littorina littorea) from archaeological levels in Northern Iberian Peninsula caves. LABORATORY AND ANALYTICAL INFORMATION Lab: Biomolecular Stratigraphy Laboratory (E.T.S.I.Minas) Lab PI: José E. Ortiz, Yolanda Sánchez-Palencia, Trinidad Torres Preparation date: Apr 2010 through Nov 2018 Pretreatment: HCl 2N AA fraction = AMINO FRACTION Hydrolysis procedure: 20 hr at 100°C in 20 µL/mg of 7 M HCl under N2 Bleach: No/yes Analytical method: RLPC Instrumental programming: RPLC buffer gradient Concentration yes Area or height ratio: Area Blank corrections: none Response factors: none Data screening criteria: Rejection criteria: 1 = L-Ser/L-Asp > 0.8; 2 = Asp or Glu D/L > ± 2s beyond group mean 3 = Asp or Glu D/L fall off the covarience trend

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/aar/ortiz2018spain/ortiz2018spain.txt NOAA Template File; Northern Spain Littorina littorea Amino Acid Racemization Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/aar/ortiz2018spain/ortiz2018spain.xlsx Excel File; Northern Spain Littorina littorea Amino Acid Racemization Data USA/NOAA DIF Version 9.8.4 2019-06-25 2019-06-25