526

Site number:

526

Authors:

IBC, GGC

Date recorded:

1988/01/06

Reason Sampled:

Soil weathering examination

Description:

At the western end of Alatna Valley and approximately 2km east of Battleship Promontory; the site is in a patterned ground crack where wind-blown sand is accumulating

Altitude:

900 m

Aspect:

Nil

Slope:

0 °

Climate

Soil climate zone:

Coastal Mountain, xerous to subxerous

Estimated mean annual temperature:

-28 °C

Frozen ground depth:

0 cm

Frozen type:

Frozen comment:

Geology

Geological setting:

Alatna Valley has formed through ice recession from the Benson Glacier and ice from Staten Island Heights; the local rocks are extensive Beacon Sandstone outcrops capped with Ferrar Dolerite; the high sand content may be due to incorporation of wind-blown sand from erosion of adjacent dolerite and sandstone outcrops

Patterned ground:

Moderately developed nets; 50cm deep active cracks containing boulders and sand accumulations

Surface weathering or surface features:

Boulders up to 1m are moderately rounded and stained; some show distinct exfoliation; movement of boulders into the patterned ground cracks is active; windblown sand is also accumulating

Soil

Soil parent material:

Windblown largely pre-weathered sand derived from fretting and abrasion of local rocks

Previous disturbance:

Nil

Soil weathering stage:

1 (Campbell & Claridge 1975)

Soil moisture status:

Local snow patches but no water or soil moistening observed

Biological activity:

Nil observed