Ross Sea Region Soil Sites
354000
354
8-Dec-1972
IBC, GGC
Wright Valley, McMurdo Dry Valley region, near Lake Vanda
Soil weathering examination
USGS 1:50,000 Antarctic Topo. Ser. Lake Vanda Quadrangle
B&W Pro & Lsc
No
161.5000
-77.5500
77deg 33.0'S
-161deg -30.0'E
cf. Notes for DESCR below
4
N
275
cf. Notes for GEOLAND below
(4o)
Dry site, no snow patches
-23
Central Mountain
Sandy gravel till from predominantly granite and dolerite; fine materials are possible pre-weathered
Nil observed
Weakly developed broad nets with 50cm troughs
SURFACE WEATHERING or |
SURFACE FEATURES |
Surface staining and polish is weak; some faceting and exfoliation is moderately advanced; coarse grained dolerite and granite are partly crumbled; a |
moderately developed cobble/pebble pavement with few scattered boulders |
Nil
354a 4-0cm
101
surface cobbles and pebbles and granular sand
102
mainly subrounded and non to weakly stained,
354b 0-10cm
201
yellowish brown (10YR 5/6) sandy cobble gravel
202
moderately cohesive
203
moderately developed vesicular structure
204
rock particles angular and unstained with some crumbly
205
distinct boundary,
354c 10-20cm
301
dark yellowish brown (10YR 4/6) sandy gravel
302
moderately cohesive
303
scattered salt flecks
304
rock particles subangular and unstained
305
some smaller rock particles weakly to moderately altered
306
indistinct boundary,
354d 20-45cm
401
yellowish brown (10YR 5/6) sandy bouldery gravel
402
loose
403
rock particles angular and unstained
404
some smaller rock particles weakly to moderately altered
405
indistinct boundary,
354e 45-80cm
501
yellowish brown (10YR 5/6) bouldery sandy gravel
502
moderately cohesive
503
slightly frosted
504
some smller rock particles weakly to moderately altered
Yes
a,b,c,d,e
Dry frozen
75
3
(>75cm)
Descr
On the floor of Wright Valley, approximately 1.5km SW of Lake Vanda; on a high valley floor moraine bench surface and about 250m out from the valley side |
slopes; the site is on a slight rise away from any possible accession of material from the valley sides; a slightly uneven surface with minor hummocks and |
shallow gullies |
Geoland
The tills of Wright Valley have derived from a complex sequence of movements of ice both up and down valley; on the lower valley surfaces the tills at the W |
end are thought to originate from former advance of the Wright Upper Glacier glacial activity in Wright Valley; this till may represent one of the most eastward |
of the latest sequence of upper Wright Valley deposits |
Soluble Salt |
Concentration |
35400001
18.00
35400002
86.00
35400003
88.00
35400004
78.00
35400005
83.00
35400006
35400001
35400002
35400003
35400004
35400005
35400006
halite
35400001
35400002
35400003
35400004
35400005
35400006
12-Dec-2005
Page 311 of 896
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