336

Site number:

336

Authors:

IBC, GGC

Date recorded:

1972/11/30

Reason Sampled:

Soil weathering examination

Description:

Sessrumnir Valley in the Asgard Range on the SE side on a bouldery till surface 50m from the cirque head alpine glacier; a bouldery uneven sloping surface

Altitude:

1750 m

Aspect:

SE

Slope:

15 °

Climate

Soil climate zone:

Inland Mountain

Estimated mean annual temperature:

-27 °C

Frozen ground depth:

15 cm

Frozen type:

Hard ice-cemented over stagnant glacial ice

Frozen comment:

15cm

Geology

Geological setting:

Alpine valleys of the Asgard Range are amongst the oldest known landscapes in Antarctica dating back to the Miocene based on till, soil and volcanic ash deposits; the present cirque head glacier is a remnant of a former glacier which filled the valley; tills associated with this glacier are derived from valley head wall attrition of dolerite and are very bouldery and young; the till age is probably Alpine I but the soil materials are probably pre-weathered

Patterned ground:

Weakly developed patterned ground cracks and ice-cored; inactivity may be due to lower temperatures

Surface weathering or surface features:

Boulders up to 1.75m; mostly subangular but some rounding; little fragmentation; moderate surface staining that may be inherited from head wall rock source; a few scattered surface salts; no pavement

Soil

Soil parent material:

Bouldery doleritic till with some sandstone

Previous disturbance:

Nil

Soil weathering stage:

2 (Campbell & Claridge 1975)

Soil moisture status:

Extensive snow in pockets and amongst boulders; no thawing or soil moistening

Biological activity:

Nil observed but endolithic lichens common in sandstone