738

Site number:

738

Authors:

IBC, GGC, DS

Date recorded:

1994/01/06

Reason Sampled:

For determination of sources and levels of soil contaminants around Scott Base

Description:

SS3 T1; the site is in the floor of a shallow depression or gully which carries a small amount of melt water from an adjacent snow patch; the location is 13.5m west from the SE corner of the old Scott Base lab building

Altitude:

16 m

Aspect:

E

Slope:

7 °

Climate

Soil climate zone:

Coastal mountain

Estimated mean annual temperature:

-18 °C

Frozen ground depth:

18 cm

Frozen type:

Ice-cemented

Frozen comment:

18

Geology

Geological setting:

The materials comprise volcanics of the McMurdo Volcanics Formation mainly as scoriaceous lava flows; the surface materials are a thin cover of mainly fractured bedrock with addition of some glacially derived granular and pebble clasts from outside the immediate area; the volcanic bedrock has been considerably fractured by patterned ground freeze thaw; the surface age is probably very late Pleistocene (Ross Sea Glaciation) having been modified by McMurdo Sound filling glacial ice

Patterned ground:

Patterned ground cracks are 20cm deep and 50cm wide; cracks may be due to frozen ground shrinkage following earlier ground disturbances

Surface weathering or surface features:

Unweathered surface with coarse angular fractured scoria flow rock; some scattered surface small salt efflorescences

Soil

Soil parent material:

Fragmented coarse bouldery volcanic bedrock possibly derived largely as slope drift

Previous disturbance:

Probably no previous mechanical disturbance of this site; probably limited human activity being within the geomagnetic area but there may be influences from the adjacent building and associated wires etc.

Soil weathering stage:

6 1 (Campbell & Claridge 1975)

Soil moisture status:

Xerous to subxerous; the site is wet and the soil moist throughout due to up slope runoff water

Biological activity:

Green algae in the runoff water