624

Site number:

624

Authors:

IBC, GGC, MRB

Date recorded:

1991/11/26

Reason Sampled:

Soil moisture and permafrost investigations

Description:

Approximately 4.3km NE of Marble Point on the east side of the runway, approximately 100m from the NE end; a sidecast mound about 1m high in gently sloping terrain, formed by previous bulldozing in the 1950's; the ssite is at the centre of the mound

Altitude:

65 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

90 cm

Frozen type:

Hard ice-cemented

Frozen comment:

90cm

Geology

Geological setting:

The surface adjacent to the airstrip has been heavily disturbed during the runway construction; areas of cut and fill deposits and side-castings are common; the rocks are dominantly granodiorite, granite, marble and gneiss; the site was examined to assess the extent of water accumulation in the permafrost 35 years after the construction activity

Patterned ground:

Nil

Surface weathering or surface features:

Surface clasts are a mixture of unoxidised clasts and partly oxidised clasts; many clasts have calcium carbonate coatings

Soil

Soil parent material:

Approximately 75cm of sandy gravel fill, from marble, granite and gneiss

Previous disturbance:

Extensive construction activity and earth-moving in the late 1950's

Soil weathering stage:

1 (Campbell & Claridge 1975)

Soil moisture status:

A dry site, no adjacent snow patches or soil moistening

Biological activity:

Nil at site; moss patches and cyanobacteria are common locally