Geologic Studies in Alaska by the U.S. Geological Survey, 1992

LATE HOLOCENE LONGITUDINAL AND PARABOLIC DUNES IN NORTHERN ALASKA
the lower paleosol yielded a radiocarbon age of maximum width, and the top of the dune is about 2 m
2,420+80 yr B.P. (table 1). above the adjacent land surface. The north arm of the
At site 3, a 7.6-m-high coastal bluff along Hanison parabolic dune is as much as 3 m thick and the sand is
Bay truncates a compound parabolic dune (fig. 7) that underlain by a paleosol 10 to 20 cm thick (fig. 8)
opens to the northeast and has a long axis that trends N. composed of sandy humus that has yielded a radiocarbon
78" E. The parabolic dune is 273 m long and 137 m in age of 5,745+115 yr B.P. (table 1). A better maximum
METERS
3-
1
ossil tundra mats @aleosols)
Eolian sand
Cryoturbated sandy humus
-$%->'2,29( )*GB~
-- - - - - - - - - --- - --~-Q891)- - --
Enlian sand
Figure 4. Diagrammatic cross section showing location of dated paleosol, site 1 (fig. 3).
Figure 5. Oblique aerial photograph, looking east-northeast, showing longitudinal dune truncated by lake bluff at site 2.
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