Permafrost and soil moisture examinations and soil temperature recording; a datalogger with 6 temperature probes to 65cm depth was installed at this site for continuous recording over several years; the teemperature records are available
Description:
Approximately 4.2km NW of Marble Point peninsula and approximately 300m W of the Marble Point Air Facility; about 400m from the Wilson Piedmont Glacier; a slightly hummocky moraine surface with low knolls up to about 2m high; the site is on a gentle slope below the crest of the knoll
Altitude:
75 m
Aspect:
SW
Slope:
3 °
Location Data
Observer
IBC
GGC
GPS
Yes
Latitude Longitude DMS
77° 24.93' S 163° 40.26' E
77° 24.9' S 163° 0.0' E
Latitude Longitude DD
-77.41550 163.67100
-77.4150 163.000
Latitude longitude precision DD
0.00008 0.00008
0.0008 0.008
Locality
Marble Point, western McMurdo Sound
Survey
USGS Antarctica Topographic Series 1:50,000; Marble Point, Antarctica
Climate
Soil climate zone:
Coastal Antarctic
Estimated mean annual temperature:
-18
°C
Frozen ground depth:
70 cm
Frozen type:
Hard ice-cemented
Frozen comment:
70cm
Geology
Geological setting:
The surface is a gently undulating till plain formed by retreat of the Wilson Piedmont Glacier; the Marble Point region is an old landscape, with deposits of phillipsite, buried soils and oxidised gneiss, which have been covered by advances of the grounded Ross Ice Shelf; later ice retreat and glaciological features have been controlled by changes in the stranded Wilson Piedmont Glacier; the till mantle is patchy and dominated largely by locally occurring rocks; granodiorite, granite, marble, gneiss, and dolerite are the main rock types present; slightly weathered material occurs at 110cm depth
Patterned ground:
Weakly developed 12-15m nets with 10cm troughs; cracks are open
Surface weathering or surface features:
Coarse clasts angular but with slight abrasion; coarse grained granite and marble are crumbly; some basement rocks with distinct surface oxidation
Soil
Soil parent material:
Stony till with 70-80% coarse material from predominantly granitic rocks
Previous disturbance:
Extensive mechanical and human activity in the region since the mid-1950's
Upper soil horizons were slightly moist alongside a small retreating snow patch in a small adjacent hollow
Biological activity:
Mosses in moist hollows and incipient water channels; cyanobacteria in ponded areas; nil observed at the site
Profile Description
Horizon
Depth
Description
613a
-3 – 0 cm
surface granular to bouldery gravel; angular and dominantly unstained; some light grey (2.5Y 7/2) carbonate coatings,
613b
0 – 3 cm
pale olive (5Y 6/3) sandy pebble and cobble gravel; loose; rock particles angular and unstained but some with light pre-oxidation; distinct boundary,
613c
3 – 15 cm
pale olive (5Y 6/3) sandy pebble and cobble gravel; loose to weakly cohesive; slightly moist; a few carbonate coatings and some silt coatings; rock particles angular and unstained; indistinct boundary,
613d
15 – 35 cm
pale olive (5Y 6/3) cobbly gravel; firm; frosted; some silt coatings; rock particles angular to subangular and unstained; distinct boundary,
613e
35 – 50 cm
pale olive (5Y 6/3) bouldery gravel; firm; frosted; some silt coatings; rock particles angular and unstained; sharp boundary,
613f
46 – 56 cm
drill core; light grey (2.5Y 7/2) sandy to silty gravel,
613g
56 – 69 cm
drill core; light grey (2.5Y 7/2) sandy to silty gravel,
613h
69 – 87 cm
drill core; light grey (2.5Y 7/2) sandy to silty gravel,
613i
87 – 99 cm
drill core; light grey (2.5Y 7/2) sandy to silty gravel,
613j
99 – 110 cm
drill core; light grey (2.5Y 7/2) sandy to silty gravel,
613k
110 – 130 cm
pale yellow to olive yellow (2.5Y 7/4 - 6/6) sandy to silty gravel; some rock particles partly altered,; drill core
613l
130 – 148 cm
drill core; pale yellow to olive yellow (2.5Y 7/4 - 6/6) sandy to silty gravel; some rock particles partly altered,