Approximately 1km W of Battleship Promontory and north of a prominent sandstone escarpment; a sloping moraine surface high on the valley side near the centre of a patterned ground polygon
Altitude:
975 m
Aspect:
N
Slope:
5 °
Location Data
Observer
IBC
GGC
GPS
No
Latitude Longitude DMS
76° 54' S 160° 59.5' E
76° 54' S 160° 56' E
Latitude Longitude DD
-76.900 160.992
-76.900 160.933
Latitude longitude precision DD
0.008 0.004
0.008 0.008
Locality
Convoy Range, Trans-antarctic Mountains, Alatna valley
Survey
Climate
Soil climate zone:
Central mountain
Estimated mean annual temperature:
-28
°C
Frozen ground depth:
35 cm
Frozen type:
Hard ice-cemented
Frozen comment:
35cm
Geology
Geological setting:
Ferrar Dolerite and Beacon Sandstone are the local rocks; the till includes some granite and other basement rock; these are not found up-valley so must have originated from the east; the till at the site appears to be the oldest of the lower valley tills
Patterned ground:
Moderately developed broad nets with 75cm troughs
Surface weathering or surface features:
A moderately bouldery surface with some upstanding boulders; moderately developed pavement; moderate to strong abrasion on up-wind side with marked staining on rock surfaces on lee sides; some wind ripples on flat lying clasts and minor pitting; some clasts with salt accumulations beneath
Soil
Soil parent material:
Dolerite, sandstone and granite stony till; the sand fraction is dominantly derived from sandstone
A north facing face with few snow patches; no soil moistening evident
Biological activity:
Nil observed
Profile Description
Horizon
Depth
Description
512a
-3
–
0
cm
surface pebbly to bouldery sandy gravel; pavement well developed with larger clasts subrounded and moderately stained,
512b
0
–
5
cm
strong brown (7.5YR 5/8) sandy gravel; weakly cohesive; moderately developed vesicular structure; a few scattered salt patches; a few ghosts; few thin darker oxidation patches around some clasts; larger rock particles mainly subangular and moderately stained with some distinctly altered; smaller particles subrounded to rounded distinct boundary,
512c
5
–
16
cm
strong brown (7.5YR 5/6) sandy gravel; moderately cohesive; weakly developed vesicular structure; may diffuse salts throughout; a few ghosts; larger rock particles subangular and weakly to moderately stained with some distinctly altered; smaller particles rounded to subrounded; distinct boundary,
512d
16
–
22
cm
strong brown (7.5YR 5/6) very sandy gravel; loose to weakly cohesive; few scattered salt flecks; larger rock particles weakly to moderately stained and moderately altered; smaller particles rounded to subrounded; indistinct boundary,
512e
22
–
35
cm
strong brown (7.5YR 5/8) gravelly sand; loose; larger particles angular, weakly to moderately stained and some distinctly altered; smaller particles rounded to subrounded; sharp boundary, on hard ice-cemented ground