502

Site number:

502

Authors:

IBC, GGC

Date recorded:

1983/01/14

Reason Sampled:

Soil characterisation

Description:

Approximately 1km W of the SW end of the Northwind Glacier; on the W side of a knoll of moraine above the Northwind glacier on a flattish but uneven surface; the surface is a till covered footslope of the Elkhorn Ridge and is dotted with numerous large (>3m) pink granite boulders

Altitude:

650 m

Aspect:

Nil

Slope:

2 °

Climate

Soil climate zone:

central mountain

Estimated mean annual temperature:

-24 °C

Frozen ground depth:

40 cm

Frozen type:

Hard ice-cemented

Frozen comment:

40cm

Geology

Geological setting:

The till sheet, composed of dolerite sandstone and granitic boulders, is distinguished by the abundant occurrence of pink coloured granite, thought to be Irizar Granite which occurs 30km to the E; the granite has been transported into the Northwind Valley from a previously enlarged Fry Glacier, possibly as a result of a former West Antarctic Ice Sheet expansion

Patterned ground:

Very weakly developed shallow, poorly demarcated large nets

Surface weathering or surface features:

Moderate staining on surface boulders, and distinct rounding, abrasion and ventifaction; some exfoliation of weathering rinds; some granite showing distinct crumbling and disaggregation; pebble pavement between larger upstanding boulders is moderately developed; small salt accumulations beneath some stones

Soil

Soil parent material:

Bouldery till from dolerite, granite and sandstone

Previous disturbance:

Nil

Soil weathering stage:

6 3 (Campbell & Claridge 1975)

Soil moisture status:

Xerous; no snow patches, snow banks or seepage

Biological activity:

Algae are absent in this highly saline pond but are present in an adjacent less saline lake