Ross Sea Region Soil Sites
803000
803
14-Jan-1995
IBC, GGC
Coombs Hills, northern Dry Valley region and to the north of Mt Brooke
Permafrost and soil moisture investigations
not recorded
Lscp & CS Profile
No
159.9020
-76.8050
76deg 48.3'S
-159deg -54.1'E
| Approximately 2.3km NNE of Mt Brooke on the floor of a valley; the site is on a flat surface, which has the appearance of a small terrace, on the undulating surface of the |
| valley floor |
0
Nil
2,015
cf. Notes for GEOLAND below
1
-3.7
5
-5.9
10
-6.5
15
-6.8
20
-6.8
30
-6.9
40
-7.7
50
-8.6
60
-9.7
70
-10.6
80
-11.3
90
-11.6
100
-12.5
110
-13.4
120
-14.4
130
-15.5
| Xerous; several snowfalls and a recent fall within 12 hours also considerable drift snow; most |
| snow cover removed by wind and ablation within 24 hours; some small semi-permanent snow |
| patches nearby, |
-32
Central Mountain
Dominantly dolerite/volcanic till but with the fine fraction from the more erodible haloclastite
Nil observed at site
Weakly developed non active polygons near the site
| SURFACE WEATHERING or |
| SURFACE FEATURES |
| Moderately developed pebble and cobble pavement with occasional boulders; clasts non to weakly ventiform but without strong oxidation; salts beneath |
| some surface clasts |
Nil
803a 3-0cm
101
surface cobbles, pebbles and granules
102
subangular to subrounded and non to weakly stained,
803b 0-10cm
201
strong brown (7.5YR 5/6) gravelly pebbly sand
202
loose
203
rock particles mainly subangular and unstained, distinct boundary
803c 10-20cm
301
strong brown ( 7.5YR 5/6) gravelly pebbly sand
302
moderately cohesive
303
many diffuse salts
304
rock particles subangular and unstained
305
distinct boundary,
803d 20-55cm
401
yellowish brown to brownish yellow (10YR 5/6 - 6/6) sandy pebble and cobble gravel
402
firmly cohesive and salt cemented
403
abundant diffuse salts
404
rock particles subangular and unstained but some ghosts strongly disaggregated
405
distinct boundary,
803e 55-70cm
501
yellowish brown to strong brown (10YR 5/4 - 7.5YR 5/6) sandy gravel
502
very firm
503
ice cemented
504
some diffuse salts
505
the horizon occurs as a lens only in one side of the pit
506
rock particles subangular and unstained
507
distinct boundary,
803f 70-90cm
601
yellowish brown (10YR 5/6) pebbly to bouldery sandy gravel
602
weakly cohesive
603
some salts scattered and around stones
604
rock particles subangular and unstained
605
indistinct boundary,
803g 90-110cm
701
yellowish brown (10YR 5/6) pebbly to bouldery sandy gravel
702
weakly cohesive
703
some salts scattered around stones
704
rock particles subangular and unstained
705
distinct boundary,
803h 110-130
801
yellowish brown (10YR 5/6) pebbly to bouldery sandy gravel
802
weakly cohesive
803
some salts scattered around stones
804
rock particles subangular and unstained
805
distinct boundary,
803i 130-135cm+
901
strong brown (7.5YR 5/6) sandy pebbly and cobbly gravel , possibly a paleosol
902
loose
903
salts diffuse and around stones
904
rock particles subrounded and subangular with some partly oxidised and weakly pitted
Yes
a,b,c,d,e,f,g,h,i
dry frozen
0
4
( partially ice-cemented between 55-70cm)
Geoland
| Rocks of the area are dominantly dolerite/volcanic (doleritic but dark coloured, fine grained and with a somewhat vesicular form compared with usual dolerite) |
| 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 formed an undulating ridge and swale 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; although the land surface has a mega ripple, the |
| deposits have no dune like characteristics" |
| Soluble Salt |
| Concentration |
80300001
803a
3-0cm
-3
0
9.72
1.12
none
80300002
803b
0-10cm
0
10
1.44
79.79
2.00
none
80300003
803c
10-20cm
10
20
1.39
58.65
5.51
none
80300004
803d
20-55cm
20
55
1.67
39.42
3.92
none
80300005
803e
55-70cm
55
70
1.65
36.13
7.46
none
80300006
803f
70-90cm
70
90
1.59
29.02
2.67
none
80300007
803g
90-110cm
90
110
1.60
29.83
3.28
none
80300008
803h
110-130cm
110
130
1.48
41.20
5.28
none
80300009
803i
130
135
1.63
41.31
2.38
none
80300001
9.70
1.12
80300002
79.80
2.00
80300003
58.70
5.51
80300004
39.40
3.92
80300005
36.10
7.46
80300006
29.00
2.67
80300007
29.80
3.28
80300008
41.20
5.28
80300009
41.30
2.38
80300001
80300002
80300003
80300004
80300005
80300006
80300007
80300008
80300009
80300001
80300002
80300003
80300004
80300005
80300006
80300007
80300008
80300009
12-Dec-2005
Page 780 of 896
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