glacier terminus was farther to the north-
estuarine deposits. Glacial deposits are common
east.
also within and on the walls of major mountain val-
doa
leys, and quite prevalent, but thinner, along the
Advance outwash deposits related to Dish-
Chugach Mountain Front; higher on the moun-
no Pond moraines (late Pleistocene)--
tains, glacial deposits are more widely scattered.
Thickness 2 to 6 m, base of unit not exposed
Colluvial deposits of Holocene and late Pleistocene
in places.
age form an extensive veneer on especially the
og
Older deposits (Pleistocene)--Moderately
lower slopes of the Chugach Mountains. Other
ogx
oxidized to yellowish gray in most places.
nonglacial deposits are more restricted in areal
Thickness about 8 to 15 m; base of unit not
extent, although some are widely distributed. They
exposed. Relationship to glacial deposits
include pond, peat, estuarine, alluvial, and anthro-
not evident. In places more strongly oxi-
pogenic deposits and are mostly Holocene in age.
dized to yellowish-orange, possibly but not
necessarily indicating deposits of substan-
Deposits in stratigraphic sequence
tially greater age.
s
oe
Deposits in stratigraphic sequence, undi-
Older glacioestuarine deposits (late Pleis-
vided--Deposits that crop out in bluffs
tocene)--Interbedded diamicton, variably
along Knik Arm and are too narrow in
pebbly to cobbly silty clay and clayey silt,
map area to show individually; portrayed
silt, and fine to medium sand. Bedding
graphically in Figure A4. Individual units
commonly fairly even but strongly contort-
shown on that figure that are not other-
ed locally. Thickness 10 to 14 m; base of unit
wise shown on the map are described
not exposed. Probably deposited in glacio-
here, as are other deposits that occur only
estuarine water that occupied ancestral
in stratigraphic sequence and that are
Cook Inlet prior to glacier advances repre-
shown on the map.
sented by Dishno Pond or earlier late Pleis-
tocene moraines.
Diamicton deposits. These are poorly sorted
oei
Deposits that are somewhat indurated
(Pleistocene)--Well-bedded silt and clay lo-
mixtures of gravel, sand, silt, and minor clay-
cally and intermittently exposed below
sized material that locally includes widely scat-
mean sea level. Bedding gently warped at
tered boulders; they are commonly massive, with
one place.
minor bedding locally. Mainly of glacial origin,
pi
they are equivalent to ground-moraine deposits.
Interglacial pond deposits (Pleistocene)--
Chiefly silt and clay with some fine sand;
kd
Knik diamicton (late Pleistocene)--
commonly include marl and intermixed
Includes interbeds of silt, sand, and gravel;
and interbedded organic material (peat,
crudely bedded in some places. Thickness
twigs, and wood, commonly compressed)
at least 10 m. May be partly glacioestua-
whose age is beyond the range of the radio-
rine in origin. Probably equivalent in age
carbon-dating method. As much as a few
to Dishno Pond deposits, but may include
meters thick, overlain and underlain by
older late Pleistocene deposits.
glacial deposits. Exposed in a few roadcuts
od
Older diamicton deposits (Pleistocene)--
along Glenn Highway, at two places along
Somewhat more oxidized and compact
Eagle River, and in one Knik Arm bluff.
than most deposits of ground moraine at
the surface. Thickness at least 10 m. Possi-
Moraine deposits
bly equivalent in age to deposits older
These are subdivided primarily according to
than those of the Rabbit Creek moraine.
type of moraine (end, lateral, and several types of
ground moraine) and subordinately according to
Glacioalluvial deposits. These are chiefly pebble
correlations mainly with named end and lateral
and cobble gravel with some interbedded sand;
moraines that extend along the Chugach Moun-
they are well bedded and sorted.
tain Front where their typical localities occur.
Holocene-age moraines correlated generally with
eoa
Advance outwash deposits related to
similarly situated moraines in the southeastern
Elmendorf Moraine (late Pleistocene)--
Thickness about 10 m. Deposited as the
part of the Municipality of Anchorage, although
glacier advanced into glacioestuarine
not with the specifically named moraines there.
water or just prior to the time when the
The till that composes most moraine deposits is
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