447

Site number:

447

Authors:

IBC, GGC

Date recorded:

1978/11/21

Reason Sampled:

Soil weathering examination

Description:

On the south side of the Hatherton Glacier in the Britannia Range; on a high altitude ridge to the west of Derrick Peak; an old bedrock feldsenmeer surface with an extensive boulder cover; the site is a cleft between bedrock boulder outcrops

Altitude:

2000 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Inland Mountain

Estimated mean annual temperature:

-35 °C

Frozen ground depth:

10 > cm

Frozen type:

Frozen comment:

>10cm

Geology

Geological setting:

Ferrar Dolerite caps the ridges and forms a prominent escarpment marking the edge of the Polar Plateau; a former more extensive Polar Ice Sheet would have extended in icefalls over the escarpment; the surfaces and the soils around the edge of the escarpment at Derrick Peak provide an indication of when the Polar Ice Sheet last extended across the escarpment and into the valleys of the Hatherton Glacier

Patterned ground:

Nil; bedrock blockfield probably formed by ice wedging

Surface weathering or surface features:

Bedrock tors extend up to 1m in a blockfield landscape formed by weathering along the joint planes in the dolerite; clasts have well rounded upper surfaces with weak sculptured forms; upper surfaces are strongly oxidised and weathering rhinds are exfoliating; at clifftop edges, rocks are strongly smoothed because of greatly increased windflows

Soil

Soil parent material:

Disaggregated and exfoliated dolerite accumulated in a rock cleft

Previous disturbance:

Nil

Soil weathering stage:

6 5 (Campbell & Claridge 1975)

Soil moisture status:

Extensive snow cover but no thaw observed or soil moistening

Biological activity:

Nil observed