318

Site number:

318

Authors:

IBC, GGC

Date recorded:

1972/11/20

Reason Sampled:

Soil sequence weathering examination

Description:

On the SE side of Lake Bonney, immediately adjacent to and near the snout of the Hughes Glacier; a bouldery surface which forms part of a series (3rd) of moraine loops marking glacial stages of the Hughes Glacier; the site is on a shallow, sloping, moraine loop marked by a ridge of boulders approximately 45m from the glacier edge

Altitude:

360 m

Aspect:

NW

Slope:

10 °

Climate

Soil climate zone:

Central Mountain

Estimated mean annual temperature:

-23 °C

Frozen ground depth:

30 > cm

Frozen type:

Frozen comment:

>30cm

Geology

Geological setting:

Alpine glaciers show clear geomorphic evidence of former advance and retreat stages with a series of small closely spaced ridges or terminal moraines over about 100m indicating the former glacier position; weathering increases with distance away from the glacier, suggesting that there may be a considerable age difference between the moraine surfaces; this 3rd surface is clearly more weathered than the surfaces nearer to the glacier

Patterned ground:

Nil

Surface weathering or surface features:

Boulders forming the moraine loop are dominantly 1-2m with granites showing marked cavernous weathering, rounding and slight surface staining; the pebble pavement between boulder patches is well developed

Soil

Soil parent material:

Very bouldery granitic till with minor dolerite; there may be some reworked material

Previous disturbance:

Nil

Soil weathering stage:

6 2/3 (Campbell & Claridge 1975)

Soil moisture status:

The site is dry with no snow drift or glacier runoff

Biological activity:

Nil observed