Ross Sea Region Soil Sites
391000
391
23-Nov-1977
IBC, GGC
Wright Valley at the Western end in the Asgard Range, near the centre of Sessrumnir Valley, approximately 1.5km NE of Mt Freya
Soil weathering examination
USGS, Antarctica 1:50,000 Topo. Ser. 1977 Labyrinth Antarctica
CS Pro
No
160.9000
-77.6033
77deg 36.2'S
-160deg -54.0'E
| On a sloping surface on the W side of Sessrumnir Valley, about midway up the slope, above the clearly identifiable main granitic till deposits; an old till surface; the site is on a |
| minor shelf on the sloping surface |
6
E
1,600
cf. Notes for GEOLAND below
(6o)
Patchy snow cover with some melt on rocks but negligible surface soil moistening
-30
Inland Mountain
Sandy gravel till from sandstone and dolerite with rare granite
Nil observed
Weakly developed broad nets
| SURFACE WEATHERING or |
| SURFACE FEATURES |
| Dolerite clasts strongly pitted and stained and some coarser clasts completely disaggregated to ground surface level; some sandstone clasts with reddish |
| surface coatings; a well developed cobble and pebble pavement |
Nil at site but previous activity in the area
391a 3-0cm
101
surface cobbles and pebbles strongly stained with advanced disaggregation
102
many smaller particles strongly altered,
391b 0-8cm
201
yellowish red (5YR 5/6) sandy cobble gravel
202
moderately cohesive
203
moderately developed vesicular structure
204
scattered diffuse salt accumulations
205
some dolerite and sandstone ghosts
206
dolerite rock particles stained and moderately altered
207
indistinct boundary,
391c 8-20cm
301
yellowish red (5YR 5/6) sandy cobble gravel
302
moderately cohesive
303
many scattered salt flecks
304
some dolerite and sandstone ghosts
305
rock particles mainly angular with some distinctly altered
306
indistinct boundary,
391d 20-35cm
401
yellowish red (5YR 5/6) sandy cobble gravel
402
loose
403
rock particles subangular, some disaggregated and moderately stained
404
coarse particles partly altered
405
sharp boundary,
391e 35-40cm
501
yellowish red (5YR 5/6) sandy gravel
502
ice cemented
503
rock particles mainly angular and unaltered
504
some clay like coatings on a few rock particles
Yes
a,b,c,d,e
Hard ice-cemented
35
5
(35cm)
Geoland
| The Asgard Range is comprised of Beacon Sandstone and Ferrar Dolerite; the landscape is ancient with the high altitude valley cirques cut in pre-Miocene time; |
| Sessrumnir valley has a sequence of moraine surfaces and tills in places with well weathered soils; the soils at higher elevation typically show the greatest |
| weathering; at lower elevation in the valley mouth there are many granite erratics; these diminish with increased elevation; at this site, one weathered granitic |
| clast was found |
| Soluble Salt |
| Concentration |
39100001
16.00
39100002
83.00
39100003
73.00
39100004
66.00
39100005
42.00
39100001
39100002
39100003
39100004
39100005
39100001
39100002
39100003
39100004
39100005
12-Dec-2005
Page 348 of 896
391
