594

Site number:

594

Authors:

IBC, GGGC, MRB

Date recorded:

1990/02/01

Reason Sampled:

Soil moisture and permafrost investigations

Description:

Between Scott Base and Crater Hill, almost in a direct line, on the crest of a broad ridge adjacent to a shallow gully from which the snow cover has largely retreated, the site is on a stable surface about 50m southwest of the snowbank in the gully; the first of three sites looking at moisture differences around snow accumulations and beyond

Altitude:

75 m

Aspect:

SE

Slope:

7 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

30 cm

Frozen type:

Hard ice-cemented

Frozen comment:

30cm

Geology

Geological setting:

Rocks are predominantly scoria flows of the McMurdo Volcanics; Last Glaciation Ross 1 ice covered the site and traces of rocks (sandstone and granite granules and small pebbles) probably from the Royal Society Range can be found; the drift mantle is thin and patchy with bedrock a little below the surface

Patterned ground:

Weakly developed with some flow features; extensive redevelopment of patterned ground on nearby ground scraped surfaces

Surface weathering or surface features:

Some dark scoria clasts have a weak polish; calcium carbonate coatings beneath some clasts

Soil

Soil parent material:

Cobbly to bouldery till and slope debris predominantly from scoria with minor accessions of sedimentary and granitic rocks

Previous disturbance:

Probably light treading disturbance; nearby, extensive ground scraping

Soil weathering stage:

1 (Campbell & Claridge 1975)

Soil moisture status:

Xerous to subxerous; a dry site

Biological activity:

Nil