629

Site number:

629

Authors:

IBC, GGC, MRB

Date recorded:

1991/11/28

Reason Sampled:

Soil moisture and permafrost investigation; comparison with adjacent site 628

Description:

Approximately 350m NNE of the Marble Point Air facility buildings; on the lower slopes of a marble ridge outcrop, a few metres above a till plane surface; the site is a low mound about 1m high and 2.5m from site 628

Altitude:

70 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

57 > cm

Frozen type:

Hard ice-cemented

Frozen comment:

>57cm

Geology

Geological setting:

Above the till plane surface, till deposits are scarce and marble outcrops extensively; small pockets of shallow drift are present; the marble bedrock is crumbly with active granular disintegration; at the site, the soil shows some strong oxidation to the surface and lacks the thin cover of young drift at site 628

Patterned ground:

Nil

Surface weathering or surface features:

A well developed pebble and cobble pavement; surface staining on some clasts; some clasts partly crumbled

Soil

Soil parent material:

Granitic and dioritic undifferentiated till over fragmented bedrock

Previous disturbance:

Nil at site but the site is adjacent to a bulldozed track 10m away

Soil weathering stage:

1;4/5 (Campbell & Claridge 1975)

Soil moisture status:

A dry site with no thaw seepages; residual snow 10m away; no soil moistening evident

Biological activity:

Nil at site; moss patches and cyanobacteria are common locally