Soil development in the Beardmore Mercer (1972) in the Beardmore Glacier region are given in table 1. Glacier region, Several soil properties are useful in differentiating drifts of Antarctica different ages. The depths of oxidation, ghosts, visible salts, and consolidation increase from the Plunkett to the Dominion drifts, as do solum thickness, morphogenetic salt stage, degree of maximum color development, and weathering stage (table 2). J. G. BOCKHEIM, S.C. WILSON, and J. E. LEIDE Unpaired t-tests were performed on these morphologic proper- ties and yielded significant differences (P < 0.05) in soil de- Department of Soil Science velopment among the five drifts. Morphogenetic salt stage and University of Wisconsin Madison, Wisconsin 53706 depths of oxidation and consolidation were the most useful properties for differentiating the various drifts. In terms of development, soils on the Sirius drift were difficult to separate from those in Dominion drift, although the geometry and mor- During the 1985 austral summer, we examined soils on glacial phology of these drifts suggest they are different. drift at 10 localities in the Beardmore Glacier region (figure). Our Whereas Mayewski (1975) attributed glacial deposits along soils investigation had three major objectives: (1) to use soil the Beardmore Glacier to fluctuations of the east antarctic ice morphologic properties to differentiate drifts of different ages, sheet, Mercer (1972) relates them to grounding of the Ross Ice (2) to interpret the origin of the dirfts in the Beardmore Glacier Shelf. If Mayewski s (1975) hypothesis is correct, soils on area relative to fluctuations of the Ross Ice Shelf and the east Beardmore drift should be the same age and comparable to soils antarctic ice sheet, and (3) to assess the importance of regional on Taylor II drift (the most recent deposit of east antarctic ice in climate as a soil-forming factor in the Beardmore area. the McMurdo Sound area) (Bockheim 1982). However, if Mer- Drift units were differentiated on the basis of geometry, mor- cer s (1972) hypothesis is correct, soils on Beardmore drift phology, and surface boulder weathering features using criteria should be the same age and comparable to soils on drifts depos- previously described (Denton et al. in press). Soils on these ited during the most recent grounding of the Ross Ice Shelf, i.e., drifts were described and sampled by horizon following the Britannia I drift in the Darwin Glacier region (Bockheim and procedure of Bockhein (1979). Informal names were assigned to Wilson 1979). the various drifts. From youngest to oldest in appearance, the To test these hypotheses, we compared soils on Beardmore drifts include the Plunkett, Beardmore, Meyer, Dominion, and drift to those on Taylor II drift in upper Taylor Valley (77°50 S) Sirius. The relationships of these drifts to those described by and Britannia I drift in the Darwin Glacier region (80°S). Each of the three drifts is derived from sediments of the Beacon Super- group, and each of the soils has formed under a comparable 0 climate. Based on unpaired t-tests, the soils on Beardmore and POLAR Britannia I drifts are similar but soils on both drifts are dissimilar PLATEAU ANTARCTICA L, 90 W R9 E to soils on Taylor II drift (table 3). Therefore, our findings sup- MAP SOC ATIc port those of Mercer (1972) which suggest that the Beardmore drift was deposited during the last grounding of the Ross Ice CIWAY 80 MASSIF Shelf. ICE-FREE OR MOUNTAINOUS The Beardmore Glacier extends 194 kilometers from the polar AREAS plateau to the Ross Ice Shelf, crossing several climatic bound- MEYER DESERT aries. This unique situation allowed us to compare soil develop- BUCKLEY ISLAND ment on Beardmore drift along a latitudinal gradient from Mount Hope (83°30 S) to the Meyer Desert (85°09 S). There LIZARDLIZ PT O 85 were no significant differences (unpaired t-tests, P > 0.05) in
.4- soil morphologic properties suggesting that the factor, time, Ow EY influences soil development more strongly than regional dif- PT ferences in climate in the Beardmore Glacier region. We appreciate the support of the staff at Beardmore South
MT Camp and VXE-6. We were assisted in the field by G.H. Den- LA f THE LOUDMAKE SIR IUS Table 1. Preliminary correlation of drift sheets in the Beardmore Glacier area
This studya Mercer (1972)
4M I A055 - ,YFPIN Plunkett "youngest moraine" ICE SHELF Beardmore Beardmore III Meyer Beardmore II MT HOPE ZS E Dominion Beardmore I Sirius Sirius Geographic place names of soil-sampling localities, Beardmore Glacier region. a Informal stratigraphic names.
1986 REVIEW 93 Table 2. Summary of field properties of soils in the Beardmore Glacier region
Depths (in centimeters) of Number of Visible Salt Weathering Color
Location profiles Oxidation Solum Ghosts salts Consolidation stage stagec equivalentd
Plunkett Drift
0 8 Willey Point 1 0 0 0 0 0 4 0 7 The Cloudmaker 2 0 0 0 0 0 4 Lizard Point 1 10 0 0 0 18 Meyer Desert 14 2 0 0 0 2 0 3 18 (x) (2)a (0)a (0)a (0)a (3)a (0)a (1)a (4)
Beardmore Drift Mount Hope 4 7 0 0 0 9 11 Mount Kyffin 3 0 0 0 0 9 5 The Cloudmaker 12 1 0 0 0 10 12 Mount FalIa 1 0 0 0 0 0 6 Lizard Point 2 2 0 0 0 3 7 Buckley Island 2 3 0 0 0 5 Meyer Desert 17 7 0 2 0 3 6 41 (x) (5.4)b (0)a (1)a (0)a (6)b (1)b (1)a (7) Meyer Drift
3 9 The Cloudmaker 2 10 11 8 20 26 Ill 2-3 16 Mount Falla 3 8 11 6 6 30 100 2-3 15 Lizard Point 2 17 13 6 14 2 10 Buckley Island 2 8 0 8 0 9 Meyer Desert 21 9 8 7 9 14 Il-tV 2-3 8 30 (x) (10)c (9)b (7)b (10)b (22)c (l-lV)c (2-3)b (10) Dominion Drift
11 33 75+ IV-V 5 18 Mount Falla 1 33 33 28 8 28 100+ 4 24 Lizard Point 1 31 34 8 34 105+ ll-IV 5 15 Buckley Island 2 34 Meyer Desert 10 30 31 16 32 98+ IV-V 5 18 14 (x) (31)d (31)c (14)c (32)c (100+)d (lV)d (5)c (18) Sirius
42 10 42 100+ Il-V 4 11 Mount Sirius 3 42 30 11 40 80+ ll-IV 4 14 Mount Falla 13 46 Meyer Desert 3 33 20 16 30 90+ IV-V 5 12 19 (x) (43)e (30)c (11)c (37)c (85+)d (II-V)d (4)c (13)
a Different letters denote statistical differences (P <0.05). x = mean values all locations. b After Bockheim (1979). After Buntley and Westin (1965)—(for surface horizons). ci After Campbell and Claridge (1975).
Table 3. A comparison of soils on Beardmore drift with soils on Britannia I drift (latest advance of Ross Ice Shelf) and soils on Taylor II drift (latest advance of east antarctic ice sheet)a
Depths (in centimeters) of Salt Weathering Glaciation Number of Profiles Oxidation Solum Ghosts Visible salts Consolidation stage stage
Beardmore 34 (5.7)a (0)a (1.4)a (0)a (5.7)a (0.4)a (1.1)a Britannia I 7 (6.7)a (2.9)a (0.3)b (0)a (8.4)a (0.7)a (1.1)a Taylor II 16 (10.8)b (12.0)b (11.9)c (0)a (25.3)b (0.8)a (1.8)b
a Different letters denote statistical differences (P<0.05).
94 ANTARCTIC JOURNAL ton, B.C. Andersen, H.B. Conway, T.E. Lowell, M. Prentice, R. Campbell, lB., and G.G.C. Claridge. 1975. Morphology and age rela- Weed, and E. Vrba. This project was supported by National tionships of Antarctic soils. In R.P. Suggate and M.M. Cresswell Science Foundation grant DPP 83-19477. (Eds.), Quaternary studies. New Zealand Royal Society Bulletin, 13, 83-88. References Denton, G.H., J.G. Bockheim, R.H. Rutford, and B.G. Andersen. In press. Glacial history of the Ellsworth Mountains, West Antarctica. In Bockheim, J.G. 1982. Properties of a chronosequence of ultraxerous C. Craddock, J. Splettstoesser, and G.E Webers (Eds.) Geology of the soils in the Trans-Antarctic Mountains. Geoderma, 28, 239-255. Ellsworth Mountains, West Antarctica. Geological Society of America Bockheim, J.G. 1979. Relative age and origin of soils in eastern Wright Memoir. Valley, Antarctica. Soil Science, 128, 142-152. Mayewski, P.A. 1975. Glacial geology and late Cenozoic history of the Trans- Bockheim, J. G., and S.C. Wilson. 1979. Pedology of the Darwin Glacier Antarctic Mountains, Antarctica. (Institute of Polar Studies Report No. area. Antarctic Journal of the U.S., 14(5), 58-59. 56.) Columbus: Ohio State University Press. Buntley, G.J., and F.C. Westin. 1965. A comparative study of develop- Mercer, J.H. 1972. Some observations on the glacial geology of the mental color in a chestnut-chernozem-brunizem climosequence. Soil Beardmore Glacier area. In R.J. Adie (Ed.), Antarctic geology and Science Society of America Proceedings, 29, 579-582. geophysics. Oslo: Universitetsforlaget.
Pre-late Quaternary glaciation (Denton et al. 1984; Webb et al. 1984). This mode of glaciation contrasts markedly with relatively minor late Quaternary fluc- of the Beardmore Glacier region, tuations (Denton, Prentice, and Burckle in press). Such a Antarctica change in ice sheet behavior presents a major opportunity to understand the controls of antarctic ice volume, an important component of the global climate system. During the 1985-1986
M. L. PRENTICE austral field season, we conducted studies in the Beardmore Glacier region (figure 1) to test hypotheses for pre-late Quatern- Institute for Quaternary Studies ary glaciation. Here we report some preliminary results. University of Maine We examined exposed highlands from the Dominion Range Orono, Maine 04469 north to the Queen Elizabeth Range (figure 1). Topographic and relief here is at least equal to the heights of the numerous 4,000- Department of Geological Sciences meter peaks (figure 2). We found a variety of mud-rich glacial Brown University deposits, unconsolidated to consolidated, in addition to those Providence, Rhode island 02912 previously described (Mercer 1972). We informally refer to all these deposits, which include the Sirius Formation, as "Sirius G.H. DENTON drift" because we consider formal stratigraphic subdivision premature. Institute for Quaternary Studies and Department of Geological Sciences Sirius Drift University of Maine Orono, Maine 04469 Basal till patches. Thin patches of Sirius basal till are scattered throughout the region between elevations of 150 and 4,115 T.V. LOWELL meters. Till patches were found at eleven localities above 3,000 meters. High-elevation till outcrops between 3,490 and 3,825 Department of Geology meters on Mount Falla; at 3,170, 3,215, 3,230, 3,370, and 4,015 University of Cincinnati meters on Mount Kirkpatrick; at 4,115 meters on Mount Mack- Cincinnati, Ohio 45221 ellar; from 3,140 to 3,292 meters on Markham Plateau; and at 3,538 and 3,660 meters on Flat Top (figure 2). The till is yellow to H.C. CONWAY gray, massive, and full of striated gravel. Consolidation is varia- ble. Sirius basal till on Mount Falla and on the highest surface in Department of Chemical and Process Engineering the northern Dominion Range contains far-traveled erratics of University of Canterbury, Private Bag Shackleton Limestone. Basal till on Markham Plateau contains Christchurch, New Zealand far-traveled erratics of granite and gneiss as well as Shackleton Limestone. Bedrock beneath many till patches exhibits striat- L.E. HEUSSER ions uniformly suggesting ice flow toward the northeast. High-elevation bedrock surfaces without till cover also exhibit Lamont-Doherty Geological Observatory well-preserved striations. Fifteen separate localities were found Columbia University above 3,000 meters. Examples occur on Mount Miller between Palisades, New York 10964 3,215 and 4,220 meters; on Grindley Plateau between 3,380 and 4,220 meters; and on Flat Top between 3,000 and 3,660 meters Massive fluctuations of the antarctic ice sheet have been infer- (figure 2). These striations likewise indicate northeasterly ice red for pre-late Quaternary time from continental evidence flow. High-elevation terrain lacks a dominant topographic grain
1986 REVIEW 95