to indicate that the feldspar is weathering to mica,the mica into vermiculite, and vermiculite intomontmorillonite. The best documentation for thesynthesis of new minerals in Antarctica was ob-tained from the old soil where the fission track ageof the soil mica indicates an age of 4.1 ±0.2 millionyears in contrast to an age of 151 million years forthe parent rock mica (Jackson et al., in press). Thepreliminary conclusion of this study is that mineralsynthesis is occurring in Antarctica; however,additional dating by the fission-track method isneeded for ascertaining whether the mica is detritalor authigenic in the young and intermediate soils.

This research was supported by National ScienceFoundation grant DPP 74-20701.

References

Bardin, V. I., and V. I. Konopleva. 1975. On the weatheringprocesses and the problem of geochronology of the glacialperiod of Antarctica. In: The Antarctic Committee Reports, 1969(V. A. Bugaev, editor). New Delhi, Amerind. 130-142.

Behling, R. E. 1971. Pedological development on moraines ofthe Meserve Glacier, Antarctica. Ph.D. thesis. Columbus, TheOhio State University. 216p.

Claridge, C. C. 1965. The clay mineralogy and chemistry ofsome soils from the Ross Dependency, Antarctica. N.Z. Jour-nal of Geology and Geophysics, 8: 186-220.

Glazovskaia, M. A. (Glazovskaya). 1958. Weathering and pri-mary soil formation in Antarctica. Navc. DokI. Vyss. Skol. geol.-geogr. Nauk, 1: 63-76.

Jackson, M. L., S. Y. Lee, F. C. Ugolini, and P. A. Helmke. Inpress. Age and uranium content of antarctic soil micas by thefission particle track method. Soil science, 121.

Kelly, W. C., and J. H. Zumberge. 1961. Weathering of quartzdiorite at Marble Point, McMurdo Sound, Antarctica. journalof Geology, 69: 433-446.

Linkletter, G. 0. 1971. Weathering and soil formation in Ant-arctica dry valleys. Ph.D. thesis. Seattle, University of Wash-ington. 122p.

Ugolini, F. C. 1964. A study of pedologic processes in Antarc-tica. Final report to NSF. New Brunswick, New Jersey, Rutgers.82p.

Ugolini, F. C., and D. M. Anderson. 1973. Ionic migration andweathering in frozen antarctic soils. Soil Science, 115: 461-470.

Ugolini, F. C., J . C. Bockheim, and D. M. Anderson. 1973. Soildevelopment and patterned ground evolution in Beacon Val-ley, Antarctica. In: Permafrost: The North American Contributionto the Second International Conference. Washington, D.C., Na-tional Academy of Sciences. 783p.

Ugolini. F. C., and C. Bull. 1965. Soil development and glacialevents in Antarctica. Quaternaria, 7: 251-269.

Ugolini, F. C., and C. C. Grier. 1969. Biological weathering inAntarctica. Antarctic Journal of the U.S., IV(4): 156-157.

Examining antarctic soils with ascanning electron microscope

MoTo! KUMAI, D. M. ANDERSON,' andF. C. UG0LINI2

U.S. Army Cold Regions Research and EngineeringLaboratory

Hanover, New Hampshire 03755

Jones et al., (1973) report a study of volcanic ashfrom Antarctica by scanning electron microscopy(5EM) and by electron microprobe. The volcanicashes examined were collected at two sites nearLake Vanda in the upper Wright Valley. They con-sisted of amorphous, porous, friable, light-grayvolcanic materials. Their amorphous nature wasconfirmed by a powder X-ray diffraction analysisthat indicated an absence of crystallinity.

Here we present the results of an investigation,by SEM and energy dispersion X-ray analysis, of themorphology, degree of weathering, and chemicalspecies for six samples of recent moraines and de-composed sandstones from Antarctica (figure 1).

Energy dispersion X-ray analysis (EDxA). Eighteencommon elements (sodium, magnesium, alumi-num, silicon, phosphorus, sulfur, chlorine, potas-sium, calcium, titanium, chromium, manganese,iron, cobalt, nickel, copper, palladium, and gold)were identified easily by EDXA. The acceleratingvoltage was 20 kilovolts. Eleven elements (sodium,magnesium, aluminum, silicon, sulfur, chlorine,potassium, calcium, titanium, manganese, andiron) were determined to be in the soil samples.Chromium, palladium, and gold (used in shadow-ing) also were found. Phosphorus, cobalt, andnickel were not observed.

EDXA was carried out for standard clay mineralssuch as dickite 15c and montmorillonite 23. Thelimit of detectability was determined using stan-dard clay minerals and was found to be about 0.1percent for sodium and potassium, and 0.01 per-cent for iron.

Quantitative analysis for soil samples 2 and 3from a recent moraine in lower Wright Valley was

'Now at the National Science Foundation, Washington, D.C.20550.

'College of Forest Resources, University of Washington,Seattle, Washington 98105.

December 1976 249

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Figure 1. Beacon Valley, Wright Valley, and Lower Wright Valley Glacier, southern Victoria Land.

done by EDXA (table). Measurement 2 of soil 3 in thetable was determined to be pure silicon dioxide,indicating that the sample was quartz. The resultsdemonstrate a heterogeneity that would not be seenin bulk analysis.

SEM was used to examine soils from Beacon Val-ley, from a lateral valley adjoining Beacon Valley,and from lower Wright Valley:

Beacon Valley. A typical scanning electron

micrograph of soil 1 shows rounded grains thatwere subjected to much mechanical and chemicalweathering. Using EDXA, chemical species such asCaC12 , MgC12 , and KC1 were found on the soilgrains. Sulfur was absent. Soil 4 (figure 2a) is asandy soil derived from decomposed Beacon sand-stone: the grains are rounded, indicating substan-tial exposure to mechanical and chemical weather-ing. Rhombohedral crystals (figure 2a) found on

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Figure 2. Sandy soil sample 4 from Beacon Valley. (a) Rhombohedral crystals (CaSO 4) formed on rounded soil grains, and (b)the EDX (energy dispersion X-ray) pattern of the rhombotedral crystal.

250 ANTARCTIC JOURNAL

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251

many of the grains were identified using EDXA(figure 2b) as CaSO4 . Pure silicon was found usingEDXA and was identified as quartz. Chlorides suchas KC1, NaCl, and CaC1 2 were found on grains ofabout 30 percent of soil 4. We describe these ma-terials from the Beacon Valley as ahumic, salinesoil. This finding agrees with those of earlier in-vestigators.

Lateral valley. Soils 5 and 6 were collected on analluvial fan in the first lateral valley on the north-west side of Beacon Valley. Soil 5 (0 to 6 centimetersdeep) and soil 6 (6 to 136 centimeters deep) wereexamined using SEM and EDXA to observe their dif-ferences with depth. A cubic crystal of 8.2 micro-meters diameter resting on a mineral grain of soil 5

was confirmed by EDXA to be CaSO4 . A quartz par-ticle (figure 3a) indicating mechanical and chemicalweathering, with contamination by elements suchas potassium, calcium, and iron, was identified us-ing EDXA (figure 3b) in surface soil 6. Many mag-netite and quartz particles were found, but chloridewas not found in either soil 5 or soil 6. Ca50 4 crys-tals were found in the surface soil but not deeper;this was the only observed difference between thesurface soil and the deep soils. We classify soils 5and 6 as sandy, evaporite soil.

Lower Wright Valley. By contrast, a typical scan-ning electron micrograph (figure 4a) of soil 2 ob-tained at site 3 in the lower Wright Valley showsgrains having sharp edges, indicating weak mech-

Figure 3. Sandy soil 6 from first lateral valley. (a) Quartz particle showing weathering, and (b) the EDXA pattern indicatingquartz with contamination of potassium, calcium, and iron.

Quantitative analysis (weight percentage) by EDXA of soil samples from lower Wright Valley.

Soil 2 Soil 3

Element Measurement Measurement Measurement Measurement Measurement Measurement Measurement Measurement1 2 3 4 1 2 3 4

Na- - -Mg- 5.52.5Al12.56.112.2Si26.122.523.5S - --Cl- - -K- 3.73.1Ca5.18.0-Ti-- -Mn- - -Fe-10.8-

December 1976

anical and chemical weathering and thus a rela-tively young age. Magnetite and silicate were found.Iron, GaG12 , and KC1 were found using EDXA in 7percent of the grains. This sample is described asan ahumic, saline soil.

The grains of soil 3 (figure 4b) from site 1, lowerin elevation than site 3, also have sharp edgesformed by comminution during glacial transportand possibly by frost action after deposition. Thegrains of soil 3 have sharp edges and less weather-ing than those of soil 2. Particles of quartz, mag-netite, and silicate minerals were found in thissample using EDXA. Soil 3 is younger than soil 2(Ugolini, 1966; Ugolini and Anderson, 1973), asseen clearly in figure 4b, and is from a recentmoraine in the Trilogy Glaciation (Nichols, 1971)in lower Wright Valley.

Chloride was found using EDXA on the grains of7 percent of morainic soil specimens. We considerthat chloride probably was supplied from sea spray,by wind, and by condensation nuclei of the snowcrystals (Kumai, 1976) and remained on the soilgrains after sublimation of the snow.

In conclusion, we did not find amorphous, por-ous, friable volcanic materials in recent morainicsoils from lower Wright Valley, and we did not findthese materials in sandy, evaporite soil from theBeacon Valley or the lateral valley.

This research was supported by ILIR DA project4A 161 101A91D and by National Science Founda-tion grant Gv-30058. We thank J . H. McAlear ofEMV Associates, Inc., and J . Sayward of the U.S.

Army Cold Regions Research and EngineeringLaboratory for helpful discussion.

References

Jones, L. M., J . A. Whitney, and J . C. Stormer, Jr. 1973. Avolcanic ash deposit, Wright Valley. Antarctic Journal of theU.S., VIII(5): 270-272.

Kumai, M. 1976. Identification of nuclei and concentrations ofchemical species in snow crystals sampled at the South Pole.

Journal of Atmospheric Science, 33(5): 833-841.Nichols, R. L. 1971. Glacial geology of the Wright Valley,

McMurdo Sound. In: Research in the Antarctic. Publication, 93:292-340. Washington, D.C., American Association for the Ad-vancement of Science.

Ugolini, F. C. 1966. Soil investigation in the lower Wright Val-ley, Antarctica. Permafrost international Conference. Publication,1287: 55-61. Washington, D.C., National Academy of Sci-ences/National Research Council.

Ugolini, F. C., and D. M. Anderson. 1973. Ionic migration andweathering in frozen antarctic soils. Soil Science, 115: 461-470.

Figure 4. Morainic soils from lower Wright Valley. (a) Grains having sharp edges of soil 2, and (u) grains taving very sharpedges of soil 3, indicating very weak weathering.

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