Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Geochronology of Bonney Drift, Taylor Valley, Antarctica: Evidence for Interglacial Expansions of Taylor Glacier

S. M. Higgins, C. H. Hendy and G. H. Denton
Geografiska Annaler. Series A, Physical Geography
Vol. 82, No. 2/3, Glacial and Paleoclimatic History of the Ross Ice Drainage System of Antarctica (2000), pp. 391-409
Published by: Wiley on behalf of the Swedish Society for Anthropology and Geography
Stable URL: http://www.jstor.org/stable/521000
Page Count: 40
  • Subscribe ($19.50)
  • Cite this Item
Geochronology of Bonney Drift, Taylor Valley, Antarctica: Evidence for Interglacial Expansions of Taylor Glacier
Preview not available

Abstract

Taylor Glacier drains into Taylor Valley from Taylor Dome, a peripheral ice rise of the East Antarctic Ice Sheet (EAIS) located near the inland edge of the Transantarctic Mountains. Taylor Glacier and local alpine glaciers have expanded in the present-day interglaciation, so that they now occupy their maximum positions since the last global glacial maximum. Exposed on the floor and walls of Taylor Valley between Lake Bonney and Canada Glacier, Bonney drift represents the penultimate eastward (downvalley) advance of Taylor Glacier. Lacustrine algal carbonates, which form in shallow proglacial lakes, were found in most excavations into Bonney drift. Both in situ and reworked carbonate samples produced 49 new uranium/thorium (U/Th) dates. U/Th dates of 70 to 130 ka for samples collected from excavations and natural sections, along with geomorphologic evidence reported elsewhere in this issue, confirm that the Bonney advance of Taylor Glacier, along with the concurrent expansion of local alpine glaciers, occurred during the interglaciation corresponding with marine isotope stage (MIS)5. In addition, δ 18O values (-35 to -43‰) of the algal carbonates confirm deposition in a proglacial lake fed by Taylor Glacier meltwater. The detailed distribution of U/Th dates shows that Bonney ice advances occurred in substages 5a, 5c, and 5e. The δ 18O record of the Taylor Dome ice core also indicates ice thickening during these same intervals. The inclusion of older carbonates in Bonney drift affords evidence for proglacial lakes during MIS 7 (160 to 240 ka), MIS 9 (270 to 330 ka), and MIS 11 or older (>370 ka). It is probable that these proglacial lakes were also associated with interglacial expansions of Taylor Glacier. This terrestrial U/Th geochronology affords a regional constraint on the late Quaternary behavior of the peripheral sector of the EAIS drained by Taylor Glacier, consistent with expansion during global interglaciations and recession during global glaciations.

Page Thumbnails

  • Thumbnail: Page 
391
    391
  • Thumbnail: Page 
392
    392
  • Thumbnail: Page 
393
    393
  • Thumbnail: Page 
394
    394
  • Thumbnail: Page 
395
    395
  • Thumbnail: Page 
396
    396
  • Thumbnail: Page 
397
    397
  • Thumbnail: Page 
398
    398
  • Thumbnail: Page 
399
    399
  • Thumbnail: Page 
400
    400
  • Thumbnail: Page 
401
    401
  • Thumbnail: Page 
402
    402
  • Thumbnail: Page 
403
    403
  • Thumbnail: Page 
404
    404
  • Thumbnail: Page 
405
    405
  • Thumbnail: Page 
406
    406
  • Thumbnail: Page 
407
    407
  • Thumbnail: Page 
408
    408
  • Thumbnail: Page 
409
    409
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]
  • Thumbnail: Page 
[unnumbered]
    [unnumbered]