On the east side of Bull Pass near the southern end; below a moraine tongue near the foot of the slope below Sandy Glacier; approximately 2.8km SSW of Mt Orestes; a long sloping slightly concave and subdued surface
Altitude:
620 m
Aspect:
SW
Slope:
15 °
Location Data
Observer
IBC
GGC
GPS
No
Latitude Longitude DMS
77° 29.6' S 161° 51.5' E
77° 28.5' S 161° 47.1' E
Latitude Longitude DD
-77.4933 161.858
-77.475 161.7850
Latitude longitude precision DD
0.0008 0.004
0.004 0.0008
Locality
Wright Valley, Bull Pass
Survey
USGS, Antarctica 1:50,000 Topo. Ser. 1977 Victoria Upper Lake Antarctica
Climate
Soil climate zone:
Coastal Mountain
Estimated mean annual temperature:
-24
°C
Frozen ground depth:
96 > cm
Frozen type:
Dry frozen
Frozen comment:
>96cm
Geology
Geological setting:
Bull Pass area is complex in respect of its glaciological history; the valley side tills give an indication of the glacial and weathering sequences; south of Mt Orestes, a moraine lobe on the valley side appears to have originated from the valley side cirque occupied by Sandy Glacier; this valley side till is older and may have come from ice entering Bull Pass from Wright Valley, judged by a range of erratics
Patterned ground:
Nil
Surface weathering or surface features:
Occasional large boulders showing advanced disintegration; granite clasts oxidised on upper surfaces and many disaggregated; a moderately developed cobble, pebble to granular sand pavement; moderate surface abrasion and ventiform development
Soil
Soil parent material:
Granite, sandstone and dolerite sandy gravel till with accessions of a few other dyke rocks
A recent snowfall resulted in surface soil moistening followed by rapid drying
Biological activity:
Nil observed
Profile Description
Horizon
Depth
Description
415a
-2 – 0 cm
surface pebbles cobbles and granular sand; rock particles mainly subangular and non to weakly stained,
415b
0 – 3 cm
light yellowish brown to pale yellow (2.5Y 6/4 - 7/4) sandy gravel; moderately cohesive; strongly developed vesicular structure; some clasts strongly disaggregating; larger rock particles angular but small particles rounded and moderately stained; distinct boundary,
415c
3 – 17 cm
light olive brown (2.5Y 5/4) sandy gravel; moderately cohesive; some granite clasts strongly disaggregating; rock particles mainly angular and unstained but small particles rounded; indistinct boundary,
415d
17 – 38 cm
light olive brown (2.5Y 5/4) sandy gravel; cohesive; abundant medium salt flecks diffused through the horizon and encrustations around stones; rock particles angular and unstained but some granite clasts disaggregating; indistinct boundary,
415e
38 – 52 cm
light olive brown (2.5Y 5/4) bouldery sandy gravel with a few brownish patches around rocks; moderately cohesive; few fine salt flecks; some granite clasts disaggregating; rock particles angular and unstained; indistinct boundary,
415f
52 – 96 cm
pale olive (5Y 6/3) bouldery sandy to silty gravel; loose; rock particles angular and unstained on bouldery sandy gravel