535

Site number:

535

Authors:

IBC, GGC

Date recorded:

1988/01/10

Reason Sampled:

Soil weathering examination

Description:

At the Northeastern end of the Towle Valley; on a low moraine ridge about 150m from the Towle Glacier; on the crest of the low ridge

Altitude:

900 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Coastal Mountain, xerous to subxerous

Estimated mean annual temperature:

-24 °C

Frozen ground depth:

24 cm

Frozen type:

Hard ice-cemented

Frozen comment:

24cm

Geology

Geological setting:

Towle Valley is formed almost entirely in dolerite; the tills, moraines and soils indicate a northeasterly retreat of the Towle Glacier from the valley; land surfaces on the lower valley floor appear not to be very old; the tills may be rather old but may have been over-ridden by repeated incursions of the Towle Glacier into the valley; a few granite clasts are present; there may have been some re-working of older tills

Patterned ground:

Weakly developed with some small micro-polygons

Surface weathering or surface features:

Extensive bouldery surfaces with predominantly angular clasts; some boulders showing extensive spalling and fragmentation and some crumbling; salts encrust undersides of many clasts; surface staining nil to some distinct

Soil

Soil parent material:

Bouldery dolerite till, possibly pre-weathered

Previous disturbance:

Nil

Soil weathering stage:

6 1 (Campbell & Claridge 1975)

Soil moisture status:

Recent snow cover shows evidence of widespread thaw; the soils are moist in places and appear to be periodically wet; water occurs in some small pools

Biological activity:

Yellow lichens occur in patches; cyanobacteria in pools