@article {3213,
	title = {Reconstructing the evolution of Lake Bonney, Antarctica using dissolved noble gases},
	journal = {Applied Geochemistry},
	volume = {58},
	year = {2015},
	month = {Jan-07-2015},
	pages = {46 - 61},
	abstract = {<p id="sp0010" style="font-size: 16px; margin-top: 0px; margin-bottom: 9px; font-family: Arial, Helvetica, {\textquoteright}Lucida Sans Unicode{\textquoteright}, {\textquoteright}Microsoft Sans Serif{\textquoteright}, {\textquoteright}Segoe UI Symbol{\textquoteright}, STIXGeneral, {\textquoteright}Cambria Math{\textquoteright}, {\textquoteright}Arial Unicode MS{\textquoteright}, sans-serif; word-spacing: -0.15ex; color: rgb(46, 46, 46); line-height: 23.6800003051758px;">Lake Bonney (LB), located in Taylor valley, Antarctica, is a perennially ice-covered lake with two lobes, West Lake Bonney (WLB) and East Lake Bonney (ELB), which are separated by a narrow ridge. Numerous studies have attempted to reconstruct the evolution of LB because of its sensitivity to climatic variations and the lack of reliable millennial-scale continental records of climate in this region of Antarctica. However, these studies are limited by the availability of accurate lacustrine chronologies. Here, we attempt to better constrain the chronology of LB and thus, the evolution of past regional climate by estimating water residence times based on He, Ne and Ar concentrations and isotopic ratios in both WLB and ELB.</p><p id="sp0015" style="font-size: 16px; margin-top: 0px; margin-bottom: 9px; font-family: Arial, Helvetica, {\textquoteright}Lucida Sans Unicode{\textquoteright}, {\textquoteright}Microsoft Sans Serif{\textquoteright}, {\textquoteright}Segoe UI Symbol{\textquoteright}, STIXGeneral, {\textquoteright}Cambria Math{\textquoteright}, {\textquoteright}Arial Unicode MS{\textquoteright}, sans-serif; word-spacing: -0.15ex; color: rgb(46, 46, 46); line-height: 23.6800003051758px;"><sup style="font-size: 0.75em; line-height: 0;">3</sup>He and\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He excesses up to two and three orders of magnitude and 35\&ndash;150 times the atmospheric values are observed for WLB and ELB samples, respectively. In comparison, while measured\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar/<sup style="font-size: 0.75em; line-height: 0;">36</sup>Ar ratios are atmospheric (\&sim;295.5) in ELB, WLB samples display\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar/<sup style="font-size: 0.75em; line-height: 0;">36</sup>Ar ratios of up to \&sim;315 reflecting addition of radiogenic\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar. Both<sup style="font-size: 0.75em; line-height: 0;">4</sup>He and\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar excesses clearly identify the addition of subglacial discharge (SGD) from underneath Taylor Glacier into WLB at depths of 25\&nbsp;m and 35\&nbsp;m. He isotopic ratios suggest that He excesses are predominantly crustal (\&gt;93\%) in origin with small mantle contributions (\&lt;7\%). These crustal\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He and\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar excesses are used together with basement rock production rates of these isotopes to derive first-order approximations of water residence times for both lobes. Numerous factors capable of affecting water residence times are evaluated and corrected\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He and\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar water ages are used to place further constrains into the reconstruction of both WLB and ELB history. Combined\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He and\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">40</sup>Ar ages in WLB suggest maximum water residence times of \&sim;250\&nbsp;kyrs BP. These results support the presence of remnant water from proglacial lakes that existed during Marine Isotope Stage 7 (160\&ndash;240\&nbsp;kyrs) in WLB, in agreement with previous studies. In comparison,\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He ages in ELB are much younger (\&lt;27\&nbsp;kyrs BP) and display a complex evolutionary history that is very different from WLB.\&nbsp;<sup style="font-size: 0.75em; line-height: 0;">4</sup>He ages also suggest that the ELB ice cover formed significantly earlier (\&sim;1.5\&nbsp;kyrs BP) than previously reported. The timing of these hydrologic changes in ELB appears to correspond to regional and global climatic events that are recorded in both the Taylor Dome ice-core record as well as in other Dry Valley Lakes.</p>},
	keywords = {LTER-MCM},
	issn = {08832927},
	doi = {10.1016/j.apgeochem.2015.02.013},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S088329271500044Xhttp://api.elsevier.com/content/article/PII:S088329271500044X?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S088329271500044X?httpAccept=text/plain},
	author = {Warrier, Rohit B. and Clara M. Castro and Chris M. Hall and Kenig, Fabien and Peter T. Doran}
}
@article {1062,
	title = {Radiocarbon abundance and reservoir effects in lakes of the McMurdo Dry Valleys, Antarctica},
	journal = {Limnology and Oceanography},
	volume = {59},
	year = {2014},
	month = {05/2014},
	pages = {811-826},
	chapter = {811},
	keywords = {LTER-MCM},
	author = {Peter T. Doran and Kenig, Fabien and Lawson Knoepfle and Jill A. Mikucki and W. Berry Lyons}
}
