306

Site number:

306

Authors:

IBC, GGC

Date recorded:

1972/11/15

Reason Sampled:

Soil Characterisation

Description:

On the south side of Taylor Valley, approximately 3km east of Lake Bonney opposite La Croix Glacier; on a broad uneven gently sloping surface, about 200m N of a basalt cone; the till cover thins with bedrock exposures 30m to the south

Altitude:

450 m

Aspect:

NW

Slope:

4 °

Climate

Soil climate zone:

Central Mountain

Estimated mean annual temperature:

-23 °C

Frozen ground depth:

70 > cm

Frozen type:

Dry frozen

Frozen comment:

>70cm

Geology

Geological setting:

Glacial deposits in the area are formed from a complex interaction of advances from the Taylor Glacier with nearby alpine glaciers; granitic rocks are common and intruded by dolerite and dyke rocks but there are also numerous small volcanic cones which post-date glacial episodes; surface volcanic debris is much smaller than at site 305 and may not have been transported by ice; the volcanic material appears to lie on the surface but may not be within the soil, which would make the soil older than the volcanics

Patterned ground:

Nil

Surface weathering or surface features:

A few large adjacent 2m boulders with some cavernous weathering, surface boulders with distinct staining, rounding and some exfoliation; the pavement between larger clasts is mainly fine gravelly and moderately developed

Soil

Soil parent material:

Granitic sandy bouldery moraine with surficial basaltic scoria

Previous disturbance:

Nil

Soil weathering stage:

3 (Campbell & Claridge 1975)

Soil moisture status:

A dry site but small snow patches in the vicinity

Biological activity:

Nil observed