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Ager, T. A., 1975, hte Quaternary environmental history
of the Tanma Valley, Alaska: Columbus,
Ohio State University, Institute of Polar Studies
Repmt 54,117 p.
-1983, Holocene vegetatimal hfst6ry 09 Alaska, &
Wright, H. R., Jr. ed., LateQuaterna~y environments
the United States; Volume 2, The Holocene~
Minneapolis, University of Minnesota
Press, p. 128-141 [in press?.
Ager, T. A,, and Sims, J. D., 1981~1, Holocene pollen
end sediment record from the Tangle Lakes area,
Alaska: Palynolcgy, v. 5, p. 85-98.
-1981b, Lote Quaternaliy pollen record from Hidden
Me, Xenai Peninsula, M e
[sbs.): American
Amlation of Stratigraphic PaIynologists Annual
Meeting, 14th, New Orleans, La., 1981, Program
and Abstracts, p. 8-9'
Denton, G. H., 1974, quaternary glaciations of the
White River Valley, Alaska, with a regional synthesis
for the northern St, Was Mountains,
Alaska and Yukon Territory: Geological Society
of America Bulletin, v. 85, no. 6, p. 871-892.
Heusser, C. J., 1960, Lote Pleistocene environments of
North Pacific North America: New York, American
Geographical Weiety Sp~iel Publication 35,
308 p,
Hqkins, D. M., 1073, Sea level history in Beringia
during the last 250,000 years: Quaternary
Research, v. 3, no. 4, p. 520-540.
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late Pleistocene and Holocene time, & LaugNin,
W. S., and Harper, A. I3,, eds., The first Americans:
Affinities and adaptatiow: New York,
Gustav Fischer, p. 15-40.
Karlstrom, T. N. V., 1964, Quaternary geology of the
Henai Lowlmd and glacial histom of the Cook
Inlet region, Alsska: U.S. Geological Survey
Profasslonal Paper 443, 69 p.
Rymer, M. J., and Sims, J. D., 1982, Lekesedlment
evidence for the date of deglaclation of the
Hidden M e area, Kenai Peninsda, Alaska:
Geology, v. la, no, 6, p. 314-316,
Camrbluted be& in hte Haiocene intestidal sediment
I .tUle.babofgnUm,-Cmkblet,w
Convoluted and contorted intertidal sand-andmud
bedded sequence of the present4ay and recent
past are exposed in upper Cook Inlet at the mouth of
Knk Arm, just southwest of Point Woronzof (loc. 3,
fig. 44; fig. 66). These intertidal deposits, which are
exposed at low tide in eroded bluffs approximately
10.5 rn high, me completely covered by tidewater at
high tide (fig. 67). The bluffs are scoured by channeled
tidal currents that enter and leave Knik Arm through a
narrows formed by Point MacKenzie on the north and
Point Woronzof on the south.
The contorted sequences have abrupt boundaries
at their base and top and are separated from other
contorted sequences by flat-lying planar-bedded
sequences. Each sequence vari~ in thickness both
laterally and vertically over the 10-m-high exposure.
At the base of each convoluted sequence is a rapid
gradation (less than 2 cm) upward Into beds that are
severely deformed; that is, the contortions appear to
have formed along a sfngle bedding plane, and the
entire overlying unit to have undergone considerable
disruption (fig. 88). Dkcordances ere present at the
top of the convoluted sequences where, in some places,
the contorted beds are truncated by overlying planar
beds (fig. 69); discordances also exist within the con-
voluted sequences where contorted beds are truncated
by contorted beck (fig. 681. Each convoluted unit
resulted Prom one or more postdeposltionfd events that
preceded burhl by the overlying planaeedded
sequences.
Figure 68.-Index map of upper Cook Inlet region,
showing locatlon of study ares and approximate
distribution of interttdd mudnats at low tide.
Several beds oP peat or other concentrated or-
ganic matter, only a few millimeters thick, occur
within the mud-sand sequence. A sample Prom the
lowest organic bed observe bout 1 m above the base
of the exposure, yielded age of 3,280i90 years
ITeledyne Isotopes, laboratory No. 1-11,706). -A simiLar
age has been obtained on In tertidd deposits in a com-
parable sbatigraphic sequence near Goose Bay, about
25 km to the north. Although small peatballs, as large
as: about 15 cm in diameter, w e presently being eroded