Occur at scattered localities on mountain
dering deeper and wider channels within
slopes, especially on middle and lower
the lowland and within lateral moraines
slopes.
along the Chugach Mountain Front, along
cl
inner valleys cut lower than the floors of
Landslide deposits, undivided (Holocene
major mountain valleys, and in some nar-
and late Pleistocene)--Include a wide vari-
row gullies cut into mountain-valley
ety of materials, chiefly diamicton, with
walls, notably along the south side of
lesser gravelly silt and sand, and relatively
North Fork Campbell Creek. cwu are
minor amounts of clay and organic mater-
deposits modified or completely removed
ial; locally include rubble and some large
during urbanization.
masses of bedrock. Earthflow deposits too
cwb Deposits that conceal Bootlegger Cove For-
small to map separately present locally.
cwbu mation (Holocene)--That formation itself
Massive; nonsorted to poorly sorted. Rela-
likely to be present behind lower part of
tively loose. Thickness probably several
bluff. Possibly subject to development of
meters to possibly several tens of meters lo-
large landslides especially during great
cally in large landslides. Contacts moder-
earthquakes such as the 1964 Alaska earth-
ately well to poorly defined. Topography ir-
quake. Occur only along Ship Creek near
regular to hummocky, slopes moderate to
west edge of map area. cwbu are deposits
steep. Queried deposits alternately may be
mainly removed in conjunction with
rock-glacier, moraine, or other colluvial
urbanization.
deposits, or even in-place bedrock. Occur in
cwf Fine-grained deposits--Chiefly silt, clay,
many places on mountain slopes, and local-
and fine sand; massive to poorly bedded,
ly in mountain valleys associated with glaci-
poorly sorted. Thickness probably a few
olacustrine and lacustrine deposits, on inlet
meters. Slopes irregularly moderate to
and stream bluffs associated with wall col-
steep and particularly subject to instabil-
luvium, and on a few hills within the
Elmendorf Moraine.
ity. Occur along walls of inner valleys
clb
within mountains adjacent to lacustrine
Older landslide deposits involving Boot-
deposits, and locally along Knik Arm
legger Cove Formation (Holocene)--Proba-
northeast of Eagle Bay where fine-grained
bly gravel, sand, silt, and clay partly mixed
materials, possibly the Bootlegger Cove
to form poorly compacted diamicton. Occur
Formation, are present in bluffs behind
locally along south side of lower Ship Creek
this colluvial veneer.
Valley near west edge of map area.
cs
cld
Solifluction deposits (Holocene and Pleis-
Landslide deposits related to Dishno Pond
tocene)--Chiefly loose, organic-rich, sandy
moraines (late Pleistocene)--Identity post-
to rubbly diamicton, commonly lacking
ulated largely on basis of landforms similar
clasts larger than pebble size. Derived
to but more subdued than adjacent lateral
mostly from weathering of frost-shattered
bedrock directly upslope, seasonally mov-
of which is lacking in area of these depos-
ing very slowly down broad mountain
its. Mainly diamicton, gravel, and sand.
slopes either with the aid of interstitial or
Occur downslope from Chugach Moun-
underlying ice (solifluction in a strict
tain Front south of Ship Creek.
sense) or of water derived largely from
clm
Deposits possibly modified in a glacioestu-
arine environment--Landforms even more
snowmelt. Thickness probably 1 m to a
subdued in this lower-lying area may have
few meters. Contacts gradational to 1)
very thinly concealed bedrock, 2) other
been reworked subaqueously shortly fol-
colluvium, and 3) thicker accumulations
lowing deposition.
of material that has moved downslope by
clg
Landslide deposits involving glacioestua-
landsliding; include some landslide
rine deposits (Holocene and late Pleisto-
deposits too small to map separately. Top-
cene)--Identity postulated largely on basis
ography generally fairly smooth, but with
of irregularly lumpy, crudely lobate topog-
many minor irregularities, especially in
raphy in areas of channels adjacent to high-
the form of small lobes with flatter upper
er-lying glacioestuarine deposits. Occur
surfaces and steeper fronts. Slopes steep to
south of South Fork Chester Creek and
moderately steep. Generally unstable.
northeast of alluvial fan of South Fork
66
to contents