591

Site number:

591

Authors:

IBC, GGGC, MRB

Date recorded:

1990/01/31

Reason Sampled:

Soil moisture and permafrost investigations

Description:

Between Scott Base and Crater Hill, a small nivation cirque above and west south of a bend in the track to a US radio antennae facility; this site is the third of 5 sites sampled in sequence; this site 0.5m from the edge of a snow bank

Altitude:

70 m

Aspect:

SE

Slope:

6 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

10 cm

Frozen type:

Hard ice-cemented

Frozen comment:

10cm

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:

Minor ground shrinkage cracks from ice cement retreat

Surface weathering or surface features:

Unweathered

Soil

Soil parent material:

Bouldery till and slope debris predominantly from scoria with minor accessions of sedimentary and granitic rocks

Previous disturbance:

Nil

Soil weathering stage:

6 1 (Campbell & Claridge 1975)

Soil moisture status:

Xerous to subxerous; some moisture from adjacent snow melt

Biological activity:

Nil