633

Site number:

633

Authors:

IBC, GGC, MRB

Date recorded:

1991/11/30

Reason Sampled:

Soil moisture and permafrost investigation; examination on beach ridge surfaces of differing ages

Description:

Approximately 100m from the coast in Arnold Cove; east from the S end of the Marble Point Air Facility; on the third from the topmost distinct beach ridge surface; near the crest of the ridge

Altitude:

15 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

50 cm

Frozen type:

Hard ice-cemented

Frozen comment:

50cm

Geology

Geological setting:

The Marble Point beach ridges are a well defined set of raised beaches; they are though to have formed due to isostatic uplift; the age may range from 10,000 years; the lithology is mixed granite, gneiss, granodiorite marble with kenyite in places

Patterned ground:

Indistinct net pattern with broad, shallow sand-filled inactive cracks

Surface weathering or surface features:

Surface boulders and cobbles rounded but subsurface clasts at lower depth are subangular; granite boulders are disintegrating and some granodiorite clasts are distinctly oxidised and partly crumbly; the oxidation intensity appears to increase with proximity to the coast and may be a result of marine influence

Soil

Soil parent material:

Bouldery raised beach gravel from rocks of mixed lithology

Previous disturbance:

Human visitation with some old soil pit sites

Soil weathering stage:

1 (Campbell & Claridge 1975)

Soil moisture status:

A dry site, no adjacent snow or soil moistening

Biological activity:

Nil at site; moss patches and cyanobacteria are common locally