Ross Sea Region Soil Sites
864000
864
3-Dec-1999
IBC
Near Lake Hoare, Taylor Valley, McMurdo Dry Valley region, Transantarctic Mountains
| Long Term Ecological Research (nematode experimental area) site investigation of soil properties; this site |
| (LTER 9) was selected for repeat sampling to measure changes in soil moisture |
Lake Bonney Quadrangle, Antarctic 1:50,000 Topographic Series, USGS 1975
CS Pro & Lscp
Yes
162.8850
-77.6350
77deg 38.10'S
-162deg -53.10'E
cf. Notes for DESCR below
3
NE
75
cf. Notes for GEOLAND below
Xerous to subxerous,
-20
Coastal mountain;
Predominantly granite (65%), dolerite (10%) with minor schist, sandstone, marble and scoria; bouldery sandy gravel becoming finer (silty) at depth
Nil observed at site, nematodes present in adjacent soil; some green algae beneath marble clasts in the general area
Irregular net 20m across with trough 1m wide and 20cm deep
| SURFACE WEATHERING or |
| SURFACE FEATURES |
| Distinct (slight) surface staining on some clasts; also weak exfoliation on a few granite clasts and some weak ventifaction and nil polish; clasts are generally |
| subrounded to subangular; carbonate coatings occur beneath some surface clasts |
Site probably disturbed by foot traffic activity during biological research activities near the site
864a 2-0cm
101
surface pebbles, cobbles and boulders
102
loose
103
weakly developed pavement
104
some slight surface staining
105
clasts subangular to subrounded
106
carbonate coatings around some clasts
107
a few fine white salt flecks
108
diffuse boundary,
864b 0-2cm
201
pale olive (5Y 6/3) pebbly to bouldery sandy gravel (>2mm 54% <2mm 46%)
202
loose
203
very weakly developed vesicular structure
204
rock particles subangular to subrounded with some weak staining
205
many carbonate coatings
206
diffuse boundary
864c 2-15cm
301
pale olive (5Y 6/3) pebbly to bouldery sandy gravel (>2mm 54% <2mm 46%)
302
weakly cohesive
303
weakly developed vesicular structure
304
rock particles subangular to subrounded with larger clasts angular
305
carbonate coatings around many clasts
306
diffuse boundary,
864d 15-25cm
401
pale olive (5Y 6/3) cobbly sandy to silty gravel (>2mm 55% <2mm 45%)
402
moderately cohesive
403
moderately developed vesicular structure
404
rock particles mainly subangular to angular
405
sharp boundary,
864e 25-30cm
501
pale olive (5Y 6/3) pebbly sandy silt
502
firmly cohesive and frosted
503
moderately developed vesicular structure
504
rock particles subangular
505
sharp boundary
506
864f 30-35cm
601
pale olive (5Y 6/3) pebbly sandy silt
602
very hard, ice-cemented, on ice-cemented ground
Yes
Hard ice-cemented
30
1
(30cm)
Descr
| Adjacent to the westernmost plot, approximately 225m from Lake Hoare; the site is on the floor of an elongated depression between two low moraine ridges and |
| is 2m to the north of the LTM Algae plot; the surface is slightly concave and is moderately bouldery; this site is designated LTER 9a |
Geoland
| The deposit is unweathered Ross I till, possibly derived from the Canada Glacier but almost certainly with an up-valley influence because of the presence of |
| marble clasts from basement rocks; the tills may be fluvio-glacial owing to complex depositional ice-marginal processes as the sand % generally increases |
| downwards while there are noticeably more coarse clasts at the surface |
| Soluble Salt |
| Concentration |
86400001
864a
2-0cm
-2
0
1.96
50.00
0.13
25.60
none
86400002
864b
0-2cm
0
2
1.75
65.00
0.37
119.00
none
86400003
864c
2-15cm
2
15
1.77
70.00
0.46
78.70
none
86400004
864d
15-25cm
15
25
1.76
83.00
0.97
51.30
none
86400005
864e
25-30cm
25
30
99.00
15.66
80.20
none
86400006
864f
30-33cm
30
33
95.00
14.11
23.80
none
12-Dec-2005
Page 838 of 896
864