Long Term Ecological Research (nematode experimental area) site investigation of soil properties; this site (LTER 8) was chosen for repeat sampling every 3-4 days to see if there were measurable changes in soil moisture with time
Description:
About 1.4km SSE of Camp Hoare; 5m north of the LTM Decomposition plot, about 300m south of Lake Hoare among shallow ridge and gully topography on the lower part of the valley side; the site is to the east of a low ridge and in a 30m wide hollow on a sloping hillside; it has an uneven slightly hummocky surface; this is the fourth sampling at this site and is designated LTER 8d
Altitude:
100 m
Aspect:
NNE
Slope:
5 °
Location Data
Observer
IBC
GPS
Yes
Latitude Longitude DMS
77° 38.10' S 162° 52.50' E
Latitude Longitude DD
-77.6350 162.8750
Latitude longitude precision DD
0.0008 0.0008
Locality
Near Lake Hoare, Taylor Valley, McMurdo Dry Valley region, Transantarctic Mountains
Survey
Lake Bonney Quadrangle, Antarctic 1:50,000 Topographic Series, USGS 1975
Climate
Soil climate zone:
Coastal mountain
Estimated mean annual temperature:
-20
°C
Frozen ground depth:
32 cm
Frozen type:
Hard ice-cemented
Frozen comment:
32cm
Geology
Geological setting:
The deposit is unweathered Ross I till, possibly derived from the Canada Glacier but almost certainly with an up-valley influence because of the presence of marble clasts from basement rocks; the tills may be fluvio-glacial owing to complex depositional ice-marginal processes as the sand % generally increases downwards while there are noticeably more coarse clasts at the surface
Patterned ground:
Moderately developed 20m irregular net with 20cm deep troughs, 50cm wide
Surface weathering or surface features:
Very weak surface staining on some clasts with no pitting, exfoliation or polish; weak ventifaction on some clasts and moderate rounding; calcium carbonate coatings on undersides of many clasts
Soil
Soil parent material:
Sandy to silty gravel with the coarse fraction consisting of granite (60%) and gneiss (20%) and dolerite (10%) with minor sandstone (8%) volcanic (scoria 1%) and marble
Previous disturbance:
Site probably disturbed by foot traffic activity during biological research activities near the site
light olive grey to pale olive (5Y 6/2 - 6/3) gravelly silty sand; loose to weakly cohesive with well developed vesicular structure; rock particles unweathered with larger rock particles subangular and smaller particles subrounded; many carbonate coatings; diffuse boundary,
907c
2 – 15 cm
light olive grey (5Y 6/2) cobbly gravelly silty sand; weakly cohesive with well developed vesicular structure; rock particles unweathered and subangular to subrounded; carbonate coatings around many clasts; sharp boundary,
907d
15 – 25 cm
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly sand; moderately cohesive and moist; unweathered with rock particles subangular to subrounded; many carbonate coatings; distinct boundary,
907e
25 – 32 cm
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly silty sand; firmly cohesive and frosted; rock particles unweathered and subangular to subrounded; many carbonate coatings; sharp boundary,
907f
32 – 38 cm
light olive grey to olive grey (5Y 6/2 - 5/2) gravelly sandy silt; very hard; ice-cemented; rock particles unweathered and subangular to subrounded