The Helium Isotopic Chemistry of Lake Bonney, Taylor Valley, Antarctica: Timing of Late Holocene Climate Change in Antarctica
  • 【DOI】

    10.1007/s10498-004-2265-z

  • 【摘要】

    To better understand the long-term climate history of Antarctica, we studied Lake Bonney in Taylor Valley, Southern Victoria Land (78°S). Helium isotope ratios and He, Ne, Ar and N2 concent... 展开>>To better understand the long-term climate history of Antarctica, we studied Lake Bonney in Taylor Valley, Southern Victoria Land (78°S). Helium isotope ratios and He, Ne, Ar and N2 concentration data, obtained from hydrocasts in the East (ELB) and West (WLB) Lobes of Lake Bonney, provided important constraints on the lakersquos Holocene evolution. Based on very low concentrations of Ar and N2 in the ELB bottom waters, ELB was free of ice until 200 ± 50?years ago. After which, low salinity water flowing over the sill from WLB to ELB, covered ELB and formed a perennial ice cover, inhibiting the exchange of gases with the atmosphere. In contrast to the ELB, the WLB retained an ice cover through the Holocene. The brine in the WLB bottom waters has meteoric N2 and Ar gas concentrations indicating that it has not been significantly modified by atmospheric exchange or ice 收起<<

  • 【作者】

  • 【刊期】

    Aquatic Geochemistry 2004年3-4期

  • 【语种】

    eng