Ross Sea Region Soil Sites
318000
318
20-Nov-1972
IBC, GGC
Taylor Dry Valley, McMurdo Dry Valley region near Lake Bonney
Soil sequence weathering examination
USGS 1:50,000 Antarctic Topo. Ser. Lake Bonney Quadrangle
CS Lsc
No
162.4570
-77.7283
77deg 43.7'S
-162deg -27.4'E
cf. Notes for DESCR below
10
NW
360
cf. Notes for GEOLAND below
(10o)
The site is dry with no snow drift or glacier runoff
-23
Central Mountain
Very bouldery granitic till with minor dolerite; there may be some reworked material
Nil observed
Nil
SURFACE WEATHERING or |
SURFACE FEATURES |
Boulders forming the moraine loop are dominantly 1-2m with granites showing marked cavernous weathering, rounding and slight surface staining; the |
pebble pavement between boulder patches is well developed |
Nil
318 3-0cm
101
surface pebbly sand between scattered large boulders
102
rock particles weakly stained and subangular to subrounded,
318a 0-30cm
201
light yellowish brown (2.5Y 6/4) sandy gravel
202
loose
203
a few fine salt flecks
204
rock particles subangular and very weakly stained
205
indistinct boundary, on sandy gravel
Yes
a
30
2/3
(>30cm)
Descr
On the SE side of Lake Bonney, immediately adjacent to and near the snout of the Hughes Glacier; a bouldery surface which forms part of a series (3rd) of |
moraine loops marking glacial stages of the Hughes Glacier; the site is on a shallow, sloping, moraine loop marked by a ridge of boulders approximately 45m |
from the glacier edge |
Geoland
Alpine glaciers show clear geomorphic evidence of former advance and retreat stages with a series of small closely spaced ridges or terminal moraines over |
about 100m indicating the former glacier position; weathering increases with distance away from the glacier, suggesting that there may be a considerable age |
difference between the moraine surfaces; this 3rd surface is clearly more weathered than the surfaces nearer to the glacier |
Soluble Salt |
Concentration |
31800001
58.00
27.70
18.40
41.60
3.40
3.70
3.20
14.00
0.55
31800001
8.20
1.90
2.60
1.80
5.20
0.20
8.00
1.00
0.20
31800001
15
15
25
40
5
12-Dec-2005
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