<DIF xmlns="http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/ http://gcmd.gsfc.nasa.gov/Aboutus/xml/dif/dif_v9.8.4.xsd">
  <Entry_ID>noaa-lake-14448</Entry_ID>
  <Entry_Title>Sugan Lake, China 850 Year Ostracod Geochemical Data</Entry_Title>
  <Data_Set_Citation>
    <Dataset_Creator>Zhang, J.-W.; Holmes, J.A.; Chen, F.-H.; Qiang, M.; Zhou, A.F.; Chen, S.</Dataset_Creator>
    <Dataset_Title>Sugan Lake, China 850 Year Ostracod Geochemical Data</Dataset_Title>
    <Dataset_Release_Date>2013-05-17</Dataset_Release_Date>
    <Dataset_Publisher>NCDC-Paleoclimatology</Dataset_Publisher>
    <Data_Presentation_Form>ONLINE Files</Data_Presentation_Form>
    <Dataset_DOI>Pending</Dataset_DOI>
    <Online_Resource>https://www.ncdc.noaa.gov/paleo/study/14448</Online_Resource>
  </Data_Set_Citation>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>J.-W.</First_Name>
    <Last_Name>Zhang</Last_Name>
  </Personnel>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>J.A.</First_Name>
    <Last_Name>Holmes</Last_Name>
  </Personnel>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>F.-H.</First_Name>
    <Last_Name>Chen</Last_Name>
  </Personnel>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>M.</First_Name>
    <Last_Name>Qiang</Last_Name>
  </Personnel>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>A.F.</First_Name>
    <Last_Name>Zhou</Last_Name>
  </Personnel>
  <Personnel>
    <Role>Investigator</Role>
    <First_Name>S.</First_Name>
    <Last_Name>Chen</Last_Name>
  </Personnel>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>depth,null,null,centimeter,null,paleolimnology,null,null,N,null</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>magnesium/calcium,ostracod,null,dimensionless,null,paleolimnology,null,null,N,Eucypris inflata</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>strontium/calcium,ostracod,null,dimensionless,null,paleolimnology,null,null,N,Eucypris inflata</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>delta 18O,ostracod,null,per mil VPDB,null,paleolimnology,null,null,N,Eucypris inflata</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>age,null,null,year Common Era,null,paleolimnology,null,null,N,varve counting</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Detailed_Variable>delta 13C,ostracod,null,per mil VPDB,null,paleolimnology,null,null,N,Eucypris inflata</Detailed_Variable>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Variable_Level_1>oxygen isotopes</Variable_Level_1>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Variable_Level_1>carbon isotopes</Variable_Level_1>
  </Parameters>
  <Parameters>
    <Category>earth science</Category>
    <Topic>paleoclimate</Topic>
    <Term>paleolimnology</Term>
    <Variable_Level_1>geochemistry</Variable_Level_1>
  </Parameters>
  <ISO_Topic_Category>geoscientificInformation</ISO_Topic_Category>
  <Keyword>hydrology</Keyword>
  <Paleo_Temporal_Coverage>
    <Paleo_Start_Date>1080 AD</Paleo_Start_Date>
    <Paleo_Stop_Date>2000 AD</Paleo_Stop_Date>
  </Paleo_Temporal_Coverage>
  <Paleo_Temporal_Coverage>
    <Paleo_Start_Date>870 cal yr BP</Paleo_Start_Date>
    <Paleo_Stop_Date>-50 cal yr BP</Paleo_Stop_Date>
  </Paleo_Temporal_Coverage>
  <Data_Set_Progress>Complete</Data_Set_Progress>
  <Spatial_Coverage>
    <Southernmost_Latitude>38.8667</Southernmost_Latitude>
    <Northernmost_Latitude>38.8667</Northernmost_Latitude>
    <Westernmost_Longitude>93.8833</Westernmost_Longitude>
    <Easternmost_Longitude>93.8833</Easternmost_Longitude>
    <Minimum_Altitude>2793</Minimum_Altitude>
    <Maximum_Altitude>2793</Maximum_Altitude>
  </Spatial_Coverage>
  <Location>
    <Location_Category>Continent</Location_Category>
    <Location_Type>Asia</Location_Type>
    <Location_Subregion1>Eastern Asia</Location_Subregion1>
    <Location_Subregion2>China</Location_Subregion2>
    <Detailed_Location>Sugan Lake&gt;LATITUDE 38.8667&gt;LONGITUDE 93.8833</Detailed_Location>
  </Location>
  <Access_Constraints>None</Access_Constraints>
  <Use_Constraints>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.</Use_Constraints>
  <Data_Set_Language>English</Data_Set_Language>
  <Data_Center>
    <Data_Center_Name>
      <Short_Name>DOC/NOAA/NESDIS/NCEI</Short_Name>
      <Long_Name>National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce </Long_Name>
    </Data_Center_Name>
    <Data_Center_URL>https://www.ncdc.noaa.gov/data-access/paleoclimatology-data</Data_Center_URL>
    <Personnel>
      <Role>DATA Center Contact</Role>
      <First_Name>Bruce</First_Name>
      <Last_Name>Bauer</Last_Name>
      <Email>bruce.a.bauer@noaa.gov</Email>
      <Email>paleo@noaa.gov</Email>
      <Phone>303-497-6280</Phone>
      <Fax>303-497-6513</Fax>
      <Contact_Address>
        <Address>325 Broadway, E/NE31</Address>
        <City>Boulder</City>
        <Province_or_State>CO</Province_or_State>
        <Postal_Code>80305-3328</Postal_Code>
        <Country>USA</Country>
      </Contact_Address>
    </Personnel>
  </Data_Center>
  <Distribution>
    <Distribution_Media>online</Distribution_Media>
    <Distribution_Format>ASCII</Distribution_Format>
  </Distribution>
  <Reference>Jiawu Zhang, Jonathan A. Holmes, Fahu Chen, Mingrui Qiang, Aifeng Zhou, Shuo Chen. 2009. An 850-year ostracod-shell trace-element record from Sugan Lake, northern Tibetan Plateau, China: Implications for interpreting the shell chemistry in high-Mg/Ca waters. Quaternary International, Vol. 194, Issues 1-2, pp. 119-133. DOI: 10.1016/j.quaint.2008.05.003</Reference>
  <Summary>
    <Abstract>The Mg, Sr and Ca contents of single shells of the ostracod Eucypris inflata from sediments retrieved from Sugan Lake, on the northern Tibetan Plateau, were analysed in order to reconstruct the salinity changes during the past ~850 yr. At present, the lake water has a Mg/Ca ratio &gt;40 and carbonates precipitated in the lake in the summer are mainly monohydrocalcites. However, X-ray diffraction analysis of core sediments suggests that several carbonate phases, including aragonite and even possibly dolomite, may have precipitated in the past. During the period (before 1620 AD) when there was aragonite precipitation, the Sr/Ca ratios of ostracod shells were at a minimum and showed little variation. When there was no aragonite precipitation (after 1620 AD), the Sr/Ca ratios of ostracods may have reflected salinity changes. The generally low Mg/Ca ratios during most of the past 850 yr may have resulted from decreased Mg partitioning in high-Mg/Ca host water as ostracods physiologically exclude excess Mg. Therefore, the Mg/Ca of ostracods cannot be used as a salinity proxy. The short-lived Mg/Ca maxima after 1300 AD correspond to decreased Sr/Ca and oxygen isotopes, indicating brief periods of freshwater input. The peaks of Mg/Ca ratios showed a similar variation with temperature change during the past 700 yr, indicating possible temperature dependence during times when the Mg/Ca ratio of the water was reduced. Water chemistry, temperature and mineralogical processes may have all affected the trace-element ratios of ostracods. Combined Sr/Ca ratios, carbonate mineralogy and oxygen isotopes allowed the lake&apos;s salinity to be reconstructed during the past ~850 yr. In enclosed lakes in hyper-arid regions, especially in high-Mg/Ca waters, the trace-element chemistry of ostracod shells should be treated with care and the complex controls on trace-element should be examined before paleosalinity or paleotemperature reconstruction is attempted. 
          STUDY NOTES: Ostracod shell oxygen isotope and trace element data from Sugan Lake core SG00C, Qaidam Basin, China.
The sediments from this lake are annually laminated: varve counts were undertaken on a parallel core SG00I 
and correlation between SG00C and GC00I based on bulk carbonate oxygen isotope variations was used to develop 
a chronology for SG00C.

The stable isotope time series was originally described in Holmes et al., (2007) Geophy. Res. Lett. 34, L23403, 
doi:10.1029/2007GL032228. Note that the carbon isotope data in this dataset were not described in this publication 
and remain unpublished.</Abstract>
  </Summary>
  <Related_URL>
    <URL_Content_Type>
      <Type>GET DATA</Type>
    </URL_Content_Type>
    <URL>https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/sugan2009elements.txt</URL>
  </Related_URL>
  <Related_URL>
    <URL_Content_Type>
      <Type>GET DATA</Type>
    </URL_Content_Type>
    <URL>https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/sugan2009isotopes.txt</URL>
  </Related_URL>
  <IDN_Node>
    <Short_Name>USA/NOAA</Short_Name>
  </IDN_Node>
  <Metadata_Name>DIF</Metadata_Name>
  <Metadata_Version>Version 9.8.4</Metadata_Version>
  <DIF_Creation_Date>2018-12-11</DIF_Creation_Date>
  <Last_DIF_Revision_Date>2018-12-11</Last_DIF_Revision_Date>
</DIF>
