Ross Sea Region Soil Sites
873000
873
6-Dec-1999
IBC
Near Lake Hoare, Taylor Valley, McMurdo Dry Valley region, Transantarctic Mountains
cf. Notes for REASON below
Lake Bonney Quadrangle, Antarctic 1:50,000 Topographic Series, USGS 1975
CS Pro & Lscp
Yes
162.8870
-77.6378
77deg 38.27'S
-162deg -53.22'E
cf. Notes for DESCR below
3
N
175
cf. Notes for GEOLAND below
1
9.8
5
5.5
15
-0.2
33
-2.4
Xerous to subxerous; a 'dry' site with no adjacent snow patches
-21
Coastal mountain;
Pred. granite (45% up to 1.3m), gneiss/schist (30% up to 60cm), sandy gravel with silt incr. with depth; minor amounts of dolerite (10% up to 40cm), dyke rock (5% up to 12cm), volcanic scoria (1% up to 3cm), sandstone (2% up to 20cm) and occ. marble
Nil observed at site, nematodes present in adjacent soil; some green algae beneath marble clasts in the general area
Uneven active net 15m across 75cm wide with 30cm deep trough
| SURFACE WEATHERING or |
| SURFACE FEATURES |
| Some weak surface staining, pitting and polish nil and some weak ventifaction; rounding generally weak but stronger on upstanding boulders; carbonate |
| coatings on undersides of surface clasts |
Possible light treading associated with the adjacent LTM monitoring site
873a 2-0cm
101
surface pebbles (30%), cobbles (10%) granules and sand (30%) with some boulders (10%)
102
weakly stained
103
coarser clasts subangular to subrounded with smaller particles mainly rounded to subrounded
104
carbonate coatings beneath larger clasts
105
some thin soluble salts beneath a few dark coloured clasts
106
873b 0-2cm
201
light olive grey (5Y 6/2) gravelly sand (<2mm 52%)
202
loose
203
carbonate coatings beneath some larger clasts
204
some weak surface staining
205
rock particles mainly subangular with rounding ofd some smaller particles
206
diffuse boundary,
873c 2-15cm
301
light olive grey (5Y 6/2) gravelly sand (<2mm 49%)
302
loose
303
carbonate coatings beneath some larger clasts
304
rock particles unstained and mainly subangular
305
distinct boundary,
873d 15-25cm
401
light olive grey (5Y 6/2) gravelly silty sand
402
moderately cohesive
403
weakly developed vesicular structure
404
carbonate coatings around some clasts
405
rock particles unstained and subangular
406
distinct boundary,
873e 25-33cm
501
light olive grey (5Y 6/2) gravelly silty sand
502
firmly cohesive
503
weakly developed vesicular structure
504
rock particles unstained and dominantly subangular
505
sharp boundary,
873f 33-37cm
601
light olive grey (5Y 6/2) gravelly sand
602
very hard
603
ice-cemented
604
rock particles unstained and dominantly subangular
No
Hard ice-cemented
33
1
(33cm)
Reason
| Long Term Ecological Research (nematode experimental area) site investigation of soil properties; this site (LTER 6) is adjacent to Elevational Transect C plot |
| and was sampled at 2 to 4 day intervals to provide indications of spatial and temporal changes in soil moisture and physical properties |
Descr
| Near the Northwest corner of LTM elevational transect C plot, on an elongated prominent bench or terrace surface, about 125m above Lake Hoare; about 20m |
| from the northern edge of the bench; the bench surface has well marked patterned ground and rises southwards merging into slope deposits from the north face |
| of Andrews Ridge; some slight deflation around upstanding boulders; this site is designated LTER 6b and was immediately alongside LTER 6a |
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 and silt % generally increase |
| downwards; the till is probably older than that at lower altitude closer to the lake and may be very slightly more oxidised |
| Soluble Salt |
| Concentration |
87300001
873a
2-0cm
-2
0
1.93
50.00
0.14
29.80
none
87300002
873b
0-2cm
0
2
1.94
63.00
0.20
34.40
none
87300003
873c
2-15cm
2
15
1.71
81.00
0.72
45.30
none
87300004
873d
15-25cm
15
25
1.68
65.00
2.49
17.10
none
87300005
873e
25-30cm
25
30
1.63
77.00
2.42
20.60
none
87300006
873f
30-37cm
30
37
76.00
11.67
32.50
none
12-Dec-2005
Page 848 of 896
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