Ross Sea Region Soil Sites
796000
796
9-Jan-1995
IBC, GGC
Coombs Hills, northern Dry Valley region and to the north of Mt Brooke
Permafrost and soil moisture investigations
not recorded
CS Lscp & Profile
No
159.9270
-76.8017
76deg 48.1'S
-159deg -55.6'E
Approximately 2km NNE of Mt Brooke on the eastern side of a valley on an undulating bench like surface about 100m above the valley floor; the sample site is on the S side |
of a small low ridge forming the edge of a small basin or shallow depression |
4
NNW
2,175
cf. Notes for GEOLAND below
Xerous; several snowfalls but little thawing or soil moistening; most snow removed by wind |
and ablation; some patches of semi- permanent snow nearby |
-32
Central Mountain
Dominantly dolerite till but with the fine fraction from the more erodible haloclastite
nil observed at site
nil at site
SURFACE WEATHERING or |
SURFACE FEATURES |
some pitting on fine grained dark coloured dolerite, moderate to strong surface polish; weak to moderate ventifaction; pebble/cobble pavement is well |
developed |
nil
796a 2-0cm
101
well developed pavement of cobbles and pebbles
102
subangular to subrounded
103
weakly stained moderate to strong polish
104
salts beneath some surface stones,
796b 0-10cm
201
strong brown (7.5YR 5/6) pebbly gravelly sand
202
weakly to moderately cohesive
203
scattered fine diffuse salts
204
rock particles subangular to subrounded
205
rock particles weakly stained but with mod. to strong internal alteration & yellowish red (5Y 5/8) oxide coatings |
on crushed faces of some clasts |
206
indistinct boundary,
796c 10-20cm
301
strong brown (7.5YR 5/6) pebbly gravelly sand
302
weakly to moderately cohesive
303
diffuse salts scattered through the horizon
304
rock particles subrounded and non stained but partly altered, distinct boundary,
796d 20-40cm
401
strong brown (7.5YR 5/6) sandy gravel
402
moderately cohesive
403
abundant salt accumulations beneath and around stones
404
rock particles subrounded to subangular, unstained and partly altered, indistinct boundary,
796e 40-60cm
501
strong brown to yellowish brown (7.5YR 5/6 -10YR 5/6) sandy cobble and pebble gravel
502
moderately cohesive
503
abundant salts
504
rock particles subangular and unstained
505
distinct boundary,
796f 60-80cm
601
light yellowish brown (2.5Y 6/4) sandy cobble and pebble gravel
602
weakly cohesive
603
abundant diffuse salts
604
rock particles subangular and unstained
605
indistinct boundary,
796g 80-100cm
701
light yellowish brown (2.5Y 6/4) bouldery to pebbly gravel
702
weakly cohesive
703
abundant diffuse salts
704
rock particles subangular and unstained
705
indistinct boundary,
796h 100-120cm
801
light yellowish brown (2.5Y 6/4) sandy gravel
802
loose
803
indistinct boundary, on loose gravel
yes
hard ice cemented
0
4
(No ice cement)
Geoland
Rocks of the area are dominantly dolerite/volcanic (doleritic but dark coloured and with a somewhat vesicular form) and softer haloclastite", (earlier described as |
tillite); the haloclastite contains basement rocks, dolerite and sandstone clasts with sedimentary structures in places; it is softer and more erodible than the |
dolerite; the till cover across the area is quite variable and is generally thinner towards Mt Brooke and towards the higher ridges; the till mantle has an undulating |
surface across the landscape with a mega-ripple appearance which may relate to the manner in which the ice sheets have retreated and ablated rather than to |
subsequent landscape modification by wind",,, |
Soluble Salt |
Concentration |
79600001
796a
2-0cm
-2
0
13.96
0.45
none
79600002
796b
0-10cm
0
10
1.41
62.97
3.34
none
79600003
796c
10-20cm
10
20
1.33
75.78
4.16
none
79600004
796d
20-40cm
20
40
1.47
54.61
2.84
none
79600005
796e
40-60cm
40
60
1.61
50.37
2.99
none
79600006
796f
60-80cm
60
80
1.52
51.81
3.21
none
79600007
796g
80-100cm
80
100
1.54
23.57
2.85
none
79600008
796h
100-120cm
100
120
1.57
44.54
none
79600001
13.90
0.45
79600002
63.00
3.34
79600003
75.70
4.16
79600004
54.60
2.84
79600005
50.40
2.99
79600006
51.80
3.21
79600007
23.60
2.85
79600008
44.50
3.43
79600001
79600002
79600003
79600004
79600005
79600006
79600007
79600008
79600001
79600002
79600003
79600004
79600005
79600006
79600007
79600008
12-Dec-2005
Page 773 of 896
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