492

Site number:

492

Authors:

IBC, GGC

Date recorded:

1983/01/09

Reason Sampled:

Soil characterisation

Description:

Approximately 5km NNE of Mt Brooke, on a broad undulating ridge surface with outcrops of dolerite and Beacon Group sediments; the surface is elevated and is dominated by bedrock exposures; the site is a small flattish bench, or old felsenmeer surface, formed by a dolerite sill

Altitude:

2100 m

Aspect:

Slope:

0 °

Climate

Soil climate zone:

Central mountain

Estimated mean annual temperature:

-31 °C

Frozen ground depth:

0 cm

Frozen type:

Dry frozen

Frozen comment:

Geology

Geological setting:

Dolerite sills and dykes intrude through Beacon Group sediments; the surface is apparently devoid of till deposits although scattered erratics of hard pitted dolerite overly sandstone in places; on this old surface, there is a patchy regolith largely comprising shallow deposits of fragmental bedrock;

Patterned ground:

Nil

Surface weathering or surface features:

Surface boulders show some rounding and wind abrasion; surface exfoliation is strongly developed on coarser grained dolerite clasts; fine grained dolerite clasts are polished, strongly stained and well pitted; where bedrock is at the surface, dolerite shows strong spheroidal weathering with as much as 30cm removed by erosion; where fragmental material has accumulated in hollows, a stone pavement is strongly developed

Soil

Soil parent material:

Weathered dolerite bedrock

Previous disturbance:

Nil

Soil weathering stage:

6 5 (Campbell & Claridge 1975)

Soil moisture status:

Xerous, a patchy cover of snow from a recent fall but little thawing

Biological activity:

Nil observed