Cape Roberts soil examination for the CEE for the proposed McMurdo Sound Stratigraphic Drilling project
Description:
The site is located about 75m to the west the NZAP huts on a raised boulder gravel beach surface, about 25m west of a low rock outcrop ridge
Altitude:
2 m
Aspect:
Slope:
0 °
Location Data
Observer
GGC
IBC
GPS
No
Latitude Longitude DMS
77° 2.14' S 163° 28.3' E
77° 30' S 163° 11' E
Latitude Longitude DD
-77.03567 163.4717
-77.50 163.183
Latitude longitude precision DD
0.00008 0.0008
0.08 0.008
Locality
Cape Roberts, at the north western end of McMurdo Sound and at the northern end of the Wilson Piedmont Glacier
Survey
not recorded
Climate
Soil climate zone:
coastal Antarctic
Estimated mean annual temperature:
-17
°C
Frozen ground depth:
55 cm
Frozen type:
hard ice-cemented
Frozen comment:
55
Geology
Geological setting:
The rocks of the area are granodiorites that have been largely planed by ice movement then subject to some weathering processes by beach and wave action; isostatic uplift has resulted in beach terracing with the raised beaches comprising mainly coarse boulder gravels; some schist/gneiss and occasional dolerite clasts in the beach gravels are indicative of residual tills; bedrock outcrops widely forming an in situ large bouldery surface; fine gravel deposits occupy a small area only
Patterned ground:
Surface weathering or surface features:
pavement of boulders and pebbles is weakly developed with subrounded clasts; some have slight to moderate staining
Soil
Soil parent material:
unweathered bouldery gravel beach deposits from dominantly granodiorite and gneissic rocks
patches of algae and some moss near adjacent rock outcrops
Profile Description
Horizon
Depth
Description
713a
-3 – 0 cm
pebble and boulder pavement; subrounded with some clasts weakly stained
713b
0 – 4 cm
pale olive (5Y 6/3) sandy pebble gravel; weakly cohesive at the surface; rock particles subrounded to subangular; distinct boundary,
713c
4 – 25 cm
pale olive (5Y 6/3) bouldery gravel; loose; coarser clasts are rounded to subrounded and smaller clasts subangular to subrounded; some weak patchy oxide coatings on some clasts; indistinct boundary,
713d
25 – 40 cm
pale olive (5Y 6/3) bouldery gravel; loose; rock particles rounded to subangular and unstained; distinct boundary,
713e
40 – 55 cm
pale olive (5Y 6/3) bouldery coarse sand; moist; cohesive; rock particles subrounded to subangular; sharp boundary,
713f
55 – 62 cm
pale olive (5Y 6/3) bouldery coarse sand; very hard; ice cemented.