560

Site number:

560

Authors:

IBC, GGC

Date recorded:

1988/01/24

Reason Sampled:

Soil Weathering examination

Description:

Approximately 10km from the northern end of Brown Peninsula in a broad saddle; on the western side of the peninsula on a higher altitude surface

Altitude:

450 m

Aspect:

SW

Slope:

3 °

Climate

Soil climate zone:

Coastal Antarctic

Estimated mean annual temperature:

-20 °C

Frozen ground depth:

35 cm

Frozen type:

Hard ice-cemented

Frozen comment:

35cm

Geology

Geological setting:

Brown Peninsula comprises volcanic rocks, mainly scoria flows of the McMurdo Volcanics Group; the area was over-ridden during the Ross Glaciation by the expanded Ross Ice Sheet; evidence of extensive ice sheet covering is provided by the presence of erratics, sandstone, dolerite and granite from the west

Patterned ground:

Weakly developed broad nets; troughs 10-40cm deep; some multiple parallel troughs in places

Surface weathering or surface features:

Erratics are fresh and unweathered but are weakly ventiformed; salts beneath larger clasts are common; carbonate coatings present on undersides of some clasts

Soil

Soil parent material:

Basaltic sandy gravel, dominantly scoria, with some finer grained basalt and occasional crystalline rocks

Previous disturbance:

Nil

Soil weathering stage:

6 1 (Campbell & Claridge 1975)

Soil moisture status:

Oceanic subxerous; no local snow patches; occasional summer snow falls

Biological activity:

Nil observed