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
Altitude:
1600 m
Aspect:
E
Slope:
6 °
Location Data
Observer
IBC
GGC
GPS
No
Latitude Longitude DMS
77° 36.2' S 160° 54' E
77° 36.2' S 160° 54' E
Latitude Longitude DD
-77.6033 160.900
-77.6033 160.900
Latitude longitude precision DD
0.0008 0.008
0.0008 0.008
Locality
Wright Valley at the Western end in the Asgard Range, near the centre of Sessrumnir Valley, approximately 1.5km NE of Mt Freya
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
Patterned ground:
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
Soil
Soil parent material:
Sandy gravel till from sandstone and dolerite with rare granite
Patchy snow cover with some melt on rocks but negligible surface soil moistening
Biological activity:
Nil observed
Profile Description
Horizon
Depth
Description
391a
-3 – 0 cm
surface cobbles and pebbles strongly stained with advanced disaggregation; many smaller particles strongly altered,
391b
0 – 8 cm
yellowish red (5YR 5/6) sandy cobble gravel; moderately cohesive; moderately developed vesicular structure; scattered diffuse salt accumulations; some dolerite and sandstone ghosts; dolerite rock particles stained and moderately altered; indistinct boundary,
391c
8 – 20 cm
yellowish red (5YR 5/6) sandy cobble gravel; moderately cohesive; many scattered salt flecks; some dolerite and sandstone ghosts; rock particles mainly angular with some distinctly altered; indistinct boundary,
391d
20 – 35 cm
yellowish red (5YR 5/6) sandy cobble gravel; loose; rock particles subangular, some disaggregated and moderately stained; coarse particles partly altered; sharp boundary,
391e
35 – 40 cm
yellowish red (5YR 5/6) sandy gravel; ice cemented; rock particles mainly angular and unaltered; some clay like coatings on a few rock particles