Ross Sea Region Soil Sites
907000
907
13-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 8) was chosen for repeat sampling every 3-4 days to see if there were measurable changes in soil |
moisture with time |
Lake Bonney Quadrangle, Antarctic 1:50,000 Topographic Series, USGS 1975
CS Pro & Lscp
Yes
162.8750
-77.6350
77deg 38.10'S
-162deg -52.50'E
cf. Notes for DESCR below
5
NNE
100
cf. Notes for GEOLAND below
Xerous to subxerous; recent light snowfall all thawed
-20
Coastal mountain
Sandy to silty gravel with the coarse fraction consisting of granite (60%) and gneiss (20%) and dolerite (10%) with minor sandstone (8%) volcanic (scoria 1%) and marble
Nil observed at site, nematodes present in adjacent soil; some green algae beneath marble clasts in the general area
Moderately developed 20m irregular net with 20cm deep troughs, 50cm wide
SURFACE WEATHERING or |
SURFACE FEATURES |
Very weak surface staining on some clasts with no pitting, exfoliation or polish; weak ventifaction on some clasts and moderate rounding; calcium |
carbonate coatings on undersides of many clasts |
Site probably disturbed by foot traffic activity during biological research activities near the site
907a 2-0cm
101
cobbly sandy gravel (<2mm 35% >2mm 65%)
102
loose
103
rock particles unweathered with larger particles subrounded
104
abundant calcium carbonate coatings beneath surface clasts
105
indistinct boundary,
907b 0-2cm
201
light olive grey to pale olive (5Y 6/2 - 6/3) gravelly silty sand
202
loose to weakly cohesive with well developed vesicular structure
203
rock particles unweathered with larger rock particles subangular and smaller particles subrounded
204
many carbonate coatings
205
diffuse boundary,
907c 2-15cm
301
light olive grey (5Y 6/2) cobbly gravelly silty sand
302
weakly cohesive with well developed vesicular structure
303
rock particles unweathered and subangular to subrounded
304
carbonate coatings around many clasts
305
sharp boundary,
907d 15-25cm
401
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly sand
402
moderately cohesive and moist
403
unweathered with rock particles subangular to subrounded
404
many carbonate coatings
405
distinct boundary,
907e 25-32cm
501
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly silty sand
502
firmly cohesive and frosted
503
rock particles unweathered and subangular to subrounded
504
many carbonate coatings
505
sharp boundary,
907f 32-38cm
601
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly sandy silt
602
very hard
603
ice-cemented
604
rock particles unweathered and subangular to subrounded
No
Hard ice-cemented
32
1
(32cm)
Descr
About 1.4km SSE of Camp Hoare; 5m north of the LTM Decomposition plot, about 300m south of Lake Hoare among shallow ridge and gully topography on |
the lower part of the valley side; the site is to the east of a low ridge and in a 30m wide hollow on a sloping hillside; it has an uneven slightly hummocky surface; |
this is the fourth sampling at this site and is designated LTER 8d |
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 |
90700001
907a
2-0cm
-2
0
1.80
55.00
0.67
24.50
none
90700002
907b
0-2cm
0
2
1.55
92.00
1.05
56.30
none
90700003
907c
2-15cm
2
15
1.54
84.00
2.94
22.50
none
90700004
907d
15-25cm
15
25
1.45
76.00
4.80
18.90
none
90700005
907e
25-32cm
25
32
1.47
71.00
5.84
20.50
none
90700006
907f
32-38cm
32
38
66.00
6.14
30.70
none
12-Dec-2005
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