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Preliminary bathymetry of McCarty Fiord and Neoglacial changes of McCarty Glacier, Alaska

Open-File Report 80-424

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Abstract

Preliminary bathymetry (at 1:20,000 scale) and other scientific studies of McCarty Fiord, Alaska, Conducted by the Research Vessel Growler in 1978, showed this 15 mile-long waterway to be a narrow, deeply scoured basin enclosed by a terminal-moraine shoal. This valley was formerly filled by McCarty Glacier, which began a drastic retreat shortly after 1909; the glacier reached shallow water at the head of the fiord around 1960. The relative rate of retreat in deep water and on land is disclosed by the slower melting of stagnent ice left in a side valley. Soundings and profiles show the main channel to extend to a depth as great as 957 feet and to have the typical ' U ' shape of a glacier-eroded valley; since the glacier 's retreat, sediments have formed a nearly level deposit in the deepest part of the fiord. Old forest debris dated by carbon-14 indicates that a neoglacial advance of the glacier began before 3,395 years B.P. (before present); by 1,500 B.P. the glacier filled most of the fiord, and before the glacier culminated its advance around 1860 , two glacier-dammed lakes were formed in side valleys. (USGS)

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Preliminary bathymetry of McCarty Fiord and Neoglacial changes of McCarty Glacier, Alaska
Series title:
Open-File Report
Series number:
80-424
Edition:
-
Year Published:
1980
Language:
ENGLISH
Description:
4 maps ;89 x 67 cm.