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Diatoms in a South Pole ice core: Serious implications for the age of the Sirius Group

One of the most controversial topics of the past decade for paleoclimatologists has been the hypothesized existence of a Pliocene warm interval in Antarctica around 3.0­2.5 million years ago (Webb and Harwood 1991). Resolution of this controversy has been linked to the validity of two competing explanations for the presence of marine diatoms in glacigenic Sirius Formation (now called Sirius Group; McKelvey et al. 1991) deposits sampled from high-elevation locations (mostly higher than 1,500 meters) along a 1,000-kilometer portion of the Transantarctic Mountains (figure 1).

Figure 1. Map of Antarctica showing locations mentioned in text: B, ice stream B; DG, David Glacier; DV, dry valleys; J-9, Ross Ice Shelf Project site J-9; KG, King George Island; LH, Larsemann Hills; MIS, McMurdo Ice Shelf; OI, Ongul Islands; RG, Reedy Glacier; SD, Siple Dome; SI, Signy Island; TD, Taylor Dome; VH, Vestfold Hills. The Sirius Group outcrops at scattered locations in the Transantarctic Mountains from David Glacier southward to near Reedy Glacier. Wilkes and Pensacola subglacial basins are located west of the Transantarctic Mountains.


  • According to the "dynamic" hypothesis (Webb et al. 1984; Harwood 1986a,b; Harwood and Webb 1995), Sirius Group sediments contain reworked Pliocene marine diatoms that are thought to have been deposited originally west of the Transantarctic Mountains in the Wilkes and Pensacola subglacial basins during a Pliocene warm interval, when the east antarctic ice sheet retreated leaving a narrow ice-free seaway. Subsequent cooling and glacial expansion resulted in grounded ice overriding the basins, incorporating marine sediments and diatoms, and subsequently, emplacing them at Transantarctic Mountains locations as the Sirius Group. This may have occurred at a time when Transantarctic Mountains elevations were 1­3 kilometers lower than they are today (Webb and Harwood 1991).
  • The contrasting "stable" hypothesis argues that the east antarctic ice sheet has remained relatively unchanged for millions of years (Denton, Prentice, and Burckle 1991). Supporting data include geomorphic analyses of dry valleys landforms (Marchant et al. 1993, 1994), the preservation of delicate argon-40/argon-39­dated features in the dry valleys (McIntosh and Wilch 1995), evidence for less than 300 meters of Transantarctic Mountains uplift since the early Pliocene (Wilch et al. 1993a,b), stable isotope records from deep-sea cores that show an absolute maximum of 25 meters of sea-level increase during and since the Pliocene (Kennett and Hodell 1993, 1995), and the nature of the antarctic marine biota which suggests a stable environment over millions of years (Kennett 1995).

The diatoms in the Sirius Group represent the single key to resolving this controversy. Were these diatoms incorporated in the Sirius soon after they lived, hence providing maximum ages for Sirius emplacement, or do they represent aeolian contamination, possibly introduced long after the Sirius sediments were deposited? Here, we report on aerially transported diatoms in ice-core samples from the South Pole.

Methods and results

Material for this study comes from the 227-meter ice core drilled at the South Pole by the Polar Ice Coring Office during the 1980­1983 field seasons (Kuivinen et al. 1982). The core spans the last years between samples (stratigraphy based on information from Gow personal communication). We also sampled snow from pits at Siple and Taylor Domes.

At the National Ice Core Facility (NICL) in Denver, Colorado, the melted ice samples, which ranged in volume from 250 to 2,000 milliliters, were filtered using a Millipore system having 1.2-millimeter perforated MF "Nuclepore" filters. Dried filters were cut into six wedges, two of which were kept for archive purposes. The remaining four were placed, sample side down, on glass cover slips and cleared (made transparent) with acetic acid. Cover slips were dried and mounted on standard glass slides. Each slide was examined in its entirety at 1,000 x, and tallies from multiple slides for each sample were combined. In addition to recording diatoms, we also noted sponge spicules, silicoflagellates, pollen grains, opal phytoliths, inorganic particulates, plant fragments, and other organic fibers.

Some workers may wonder whether our samples are contaminated and, therefore, unreliable indicators of atmospheric diatom transport. We recognize three possible stages in the processing of our samples when contaminants might be introduced:

  • during drilling or core packing in the field,
  • during melting and filtering at NICL, and
  • in our laboratory when filters were prepared for examination.

At the South Pole, no source for diatoms is near the drilling or core-packing site. If contamination occurred at the latter times, one would expect to see a significant extra-antarctic component in the diatom assemblage. Because our samples are all dominated by typical antarctic species, we conclude that contamination is not a problem for this study.

Diatoms are a small but pervasive constituent of snow falling at the South Pole (and at Siple and Taylor Domes), although in a patchy pattern through both space and time (figure 2). Over 40 marine and nonmarine taxa were recorded (table). Abundances are extremely variable, ranging from nil to over 260 specimens in individual samples. Of 136 samples

Figure 2. Diatom abundance fluctuations (specimens per liter) and percentage of nonmarine specimens in the South Pole core. Ages are calendar years based on correlation with the adjacent 1981 core at South Pole (Gow personal communication).


  • 34 percent contain more than 75 percent marine specimens,
  • 4 percent are more than 75 percent nonmarine,
  • 35 percent have intermediate mixtures of marine and nonmarine taxa, and
  • the remainder are barren or are dominated by species of uncertain provenance.

Most recorded species have been reported by us or other workers from a variety of antarctic sites (table). Not all taxa we report have yet been associated with antarctic source areas and may represent transport from remote locations such as the other southern continents. Census data for individual samples will be available in a separate publication (D. Kellogg in preparation).


Taxon Sample/a A/b Habitat/c Reported locations/d  Notes
Achnanthes lanceolata  SP981 (2) 1  FR  EO, KG, SI  
Achnanthes sp. SP 981 (2) 1 FR    
Actinochlus ehrenbergi SP 440, 1460 (1) 1 MAR A  
Actinoptychus senarius SP 1460 (1) 1 MAR R1, RP  
Chaetoceros diadema TD pit D, 0 cm (1) 3 MAR   Polar waters
Chaetoceros sp. TD pit K, 93 cm (1) 3 MAR A, W  
Coscinodiscus marginatus SP 1532 (10) 1 MAR R1, RP  
Coscinodiscus radiatus SP 1532 (6) 1 MAR K (in red snow)  
Cyclotella comta SP 1704 (3) 1,3 BR A1, M, TV  
Cyclotella comta v. oligactis SP 981 (24) 1 C A`, TV  
Cyclotella glomerata SP 223 m(3) 1 FR A, M  
Cyclotella pseudostelligera ? SP 224.5 m(3) 1 BR   Often counted as C. stelligera
Cyclotella stelligera SP 981 (184) 1,3 C A1, LM, M  
Cyclotella striata ? SP 223 m(11) 1 BR    
Cyclotella sp. SP 726 (21) 1,3 C A, M, R1 Probably C. stelligera
Cymbella lunata SP 1265 (1) 1 FR SO As Encyconema gracilis
Denticulopsis hustedtii SP 1449 (1) 1 MAR A, R1, RP, W Miocene
Diploneus smithii SP 440 (1) 1 BR LH  
Diploneus sp. SP 182 (2) 1   A1  
Fragilaria pinnata SP 981 (1) 1 FR KG, LG, SI  
Fragilaria virescens SP 981 (6) 1 FR DV  
Grammatophora sp. SP-37 (1) 1 MAR A, RP  
Melosira distans SP 223 m (17) 1,3 FR A1, DV, M  
Melosira granulata SP-37 (28) 1 FR LG =Aulasoseira granulata
Melosira sp. SP 981, 458 (2) 1 FR A, M, R1 Probably M. granulata
Navicula festiva SP 223 m (2) 1 FR KG NZ (Harper, personal communication)
Navicula muticopsis SD camp (2) 2 FR DV, LM, M, RO, TV  
N. muticopsis v. evoluta TD Pit 50S, 84 cm (1) 3 FR M, TV  
Navicula muticopsis n.v. SD S50 W50 (15) 2 FR   Possible new variety?
Navicula sp. SP 1637 (2) 1,2 FR? A1, M, TV  
Nitschia aricularis ? SD S50 W50 (3) 2 FR EO  
Nitschia amphibia TD pit E, 120 cm (1) 3 FR   Arctic
Nitschia closterium TD pit I, 0 cm (1) 3 BR M  
Nitschia curta SD S50 W50 (1) 2 MAR A, M, R, R1, R2, RP, TV  
Nitschia cylindra TD pit 50S, 0 cm (11) 3 MAR A, R1, R2  
Nitschia gracilis SD S50 W50 (1) 2 FR SI  
Nitschia microcephala ? SD S50 W50 (3) 2 FR   Europe
Nitschia obliquecostata TD pit 50S, 84 cm (1) 3 MAR A, M, R1  
Nitschia sublineata TD pit D 0 cm (1) 3 MAR A, M, R1  
Nitschia sp. SP 1460, 213 m (4) 1,2 MAR/FR A, M, R1, RP, TV  
Paralia sulcata SP (5 samples) (1) 1 MAR M, RP =Melosira sulcata
Pinnularia nodosa SP 1677 (1) 1 FR   NZ (Cassie 1984)
Pinnularia maior SP 981 (2) 1 FR   Tierra del Fuego (Frenguelli 1923) (as Navicula maior); NZ (Cassie 1984)
Pinnularia sp. SP 1637 (8) 1 FR? M  
Pseudoneunotia doliolus SP 1449, 1460 (1) 1 MAR   Subtropics, Pleistocene
Rhabdonema sp. SP 1440 (1) 1 MAR M, RP  
Stephanodiscus astraea SP (6 samples) (1) 1 FR/BR   W. Europe
Stephanopyxis turris TD pit 50S, 0 cm (1) 3 MAR M, R1, RP  
Synedra fasciculata SP 981 (5) 1 FR/BR    
Tabellaria flocculosa SP 981 (2) 1 FR A1, TV  
T. fenestrata/quadriseptata SP 223 m (2) 1,2 FR A1, DV  
Thalassionema nitzschiodes SP 458, 1532 (4) 1 MAR A, M, R1, RP, TV, W See T. longissima
Thalassiosira eccentrica

TD pits B&D


3 MAR A, R1  
Thalassiosira occulus-iridis TD pits D&G(1) 3 MAR A  
Thalassiosira sp. SP 1662 (14) 1,2 MAR A, M, R1, RP  
Thalassiothrix longissima SD N50 W50 (119) 2,3 MAR A, M, R1, RP, W Includes T. nitzschiodes fragments
Trachyneis aspera TD pit E, 120 cm (1) 3 MAR A  
Trachyneis sp. TD pit D, 80 cm (1) 3 MAR    
Centric diatom fragments SP 1460 (53) 1,2,3   A, M, R1, RP, TV Probably mostly marine taxa
Pennate diatom fragments SP 981 (7) 1      
Unidentified SP 1704 (3) 1,3      

aSP=South Pole; numbers are calendar age in years A.D. or depth in meters if older than 37 B.C.; TD=Taylor Dome, pit number and depth; SD=Siple Dome pit number; numbers in parantheses are maximum value recorded for the taxon in the sample listed.

bAssemblage: 1=South Pole; 2=Siple dome; 3=Taylor dome.

cMAR=Marine; FR=nonmarine; BR=brackish; C=possibly nonmarine but common in antarctic marine samples.

dA=Amundsen Sea marine sediments (Kellogg and Kellogg 1987a), A1=sediments and/or water on Amundsen Sea islands (Kellogg and Kellogg 1987a), DV=lakes and ponds in dry valleys (Seaburg et al. 1979), EO=East Ongul Islands (Karaswa and Fukushima 1977), K=Kerguelen Island, red snow (Fritsch 1912b), KG=King George Island (Schmidt et al. 1990), M=McMurdo Ice Shelf (Kellogg and Kellogg 1987b), LG=Lake Glubokoye (Lavrenko 1966), LH=Larsemann Hills (L. Heidi) (Gillieson 1991), LM=Lake Miers, Dry Valleys (Baker 1967), R=Ponds and sediments on Ross Island (Fritsch 1912a, and/or West and West 1911), R1=Ross Sea sediments (Truesdale and Kellogg 1979), R2=Ross Sea sediments (Barron and Burckle 1987), RP=Ross Ice Shelf Project site J-9 (Kellogg and Kellogg 1986), SI=Signy Island (Oppenheim 1990), SO=South Orkney Islands (Frenguelli 1923), TV=Taylor Valley deltas (Kellogg et al. 1980), W=west antarctic ice sheet beneath ice stream B (Scherer 1991).

Sources and atmospheric transport of diatoms

Diatoms are extremely light and easily transported by winds (e.g., the well-known diatom deposits in the equatorial Atlantic derived from Saharan Africa; Folger 1970), and winds in Antarctica are known to reach very high velocity. The antarctic surface windfield is dominated by katabatic flow, outward and down from high ice domes toward the sea (Parish and Bromwich 1987). Storms tend to track around the continent. Occasional large storms break through the circumflow and penetrate to the South Pole (Bromwich and Robasky 1993). Our diatoms were probably carried by these episodic events, which occur today at most a few times annually. An alternative transport mechanism, stratospheric return (poleward) flow, is unlikely because most of our diatoms are antarctic endemics whereas most stratospheric particles are entrained in tropical areas. Terrestrial sediments containing marine and nonmarine diatoms probably serve as the most important diatom sources. We envision diatom entrainment as episodic, perhaps occurring only a few times in a decade, and responsible for the low background level of less than 20 diatoms per liter of melted ice typical for approximately 70 percent of our samples.

Samples with higher diatom concentrations may represent short periods during which higher than normal surface winds occurred in a particular source area, or in more than one area of the coastal zone.

Specific provenances for our diatoms cannot be identified because most individual species have been reported from a number of locations (table). Marine diatom-bearing sediments are widespread in the dry valleys area of the Transantarctic Mountains, especially where Late Wisconsin Ross Sea Drift (Stuiver et al. 1981; Denton et al. 1989) is exposed. The marine species reported here are present in virtually every sample of this drift that we have examined. Similar diatom-bearing sediments are probably widespread elsewhere around the continent. That most marine specimens have been reworked from subaerially exposed sediments is further suggested by the high degree of dissolution and breakage exhibited by the marine specimens. Nonmarine diatoms are also widespread in the dry valleys, in subaerially exposed deposits, and in virtually every lake, pond, or seasonal melt pool. Many of these water bodies are ephemeral or display fluctuating water levels. Complete or partial desiccation exposes fossil material for transport by winds as described above.

Diatom deposition: Implications for the Sirius Group

Diatoms settling on the polar plateau are buried and trapped in the snow. As the snow compresses to ice and flows gradually down and outward toward the ice sheet margin, the diatoms are carried along until they reach either the glacial bed or come to the surface in an area with surface ablation (where flowlines outcrop). In the former case, diatoms from many years of deposition may become concentrated at the ice bed in morainal material. Thus, atmospherically transported diatoms have the potential to result in a reworked assemblages containing diatoms of different ages.

Not all diatoms carried through the atmosphere end up in the ice. If they land on an ice- or snow-free area, they may be retransported unless they fall in cracks or crevices protected from the wind. Evidence for this diatom-trapping mechanism was presented by Burckle (1995, in preparation) who found Pliocene/Pleistocene diatoms in cracks and crevices of antarctic sedimentary rocks. Most atmospherically transported diatoms trapped in cracks and crevices of glacigenic sedimentary deposits should remain near the surface (Stroeven and Prentice 1995), but penetration is also possible, even in compact sediments such as the Sirius Group. A thin layer of snow falling on such a sediment often melts because of heat retention by the relatively dark surface, carrying small amounts of meltwater deep into the sediment by capillary action, entraining the tiny (mostly less than 100 micrometers), delicate diatoms. Penetration should be enhanced by the presence of frost cracks in the compact Sirius sediments. We have no data suggesting how deep such penetration may go but a meter or more seems possible. We conclude that atmospheric transport routinely distributes marine and nonmarine diatoms across the antarctic ice sheet. Our data demonstrate that Sirius Group contamination by younger diatoms is unavoidable because of the pervasive and widespread effects of this atmospheric transport.

Together with our work, studies by Burckle (1995, in preparation) and Burckle and Potter (1996) of diatoms in sedimentary and igneous antarctic rocks cast serious doubts on the validity of presumed in situ Pliocene marine diatoms in the Sirius Group because the Pliocene diatoms are not demonstrably associated with the glacial sediments in which they occur. Hence, the entire construct of a warm Pliocene event in Antarctica is in doubt. A more complete presentation of ideas and data presented in this paper may be found in Kellogg and Kellogg (1996).

We thank Eric Steig, Pieter Grootes, Ken Taylor, Joan Fitzpatrick, Ellen Mosely-Thompson, Jeff Hargreaves, and Todd Hinckley for assistance in ice-core sampling. Tony Gow kindly provided the stratigraphy of the 1981 South Pole core. Ben Carter of Corning-Costar supplied modified Nuclepore filters. Lloyd Burckle and Terry Hughes discussed these results and read drafts of the manuscript. Margaret Harper called our attention to a number of reports of individual species listed in table. Financial support was provided by National Science Foundation grant OPP 93-16306 to D.E. Kellogg.


Baker, A.N. 1967. Algae from Lake Miers, a solar-heated antarctic lake. New Zealand Journal of Botany, 5(4), 453­468.

Barron, J.A., and L.H. Burckle. 1987. Diatoms from the 1984 USGS antarctic cruise in the Ross Sea. In A.K. Cooper and F.J. Davey (Eds.), The antarctic continental margin: Geology and geophysics of the western Ross Sea (CPCEMR Earth Science Series, Volume 5B). Houston: Circum-Pacific Council for Energy and Mineral Resources.

Benninghoff, W.S., and A.S. Benninghoff. 1978. Airborne particles and electric fields near the ground in Antarctica. Antarctic Journal of the U.S., 13(4), 163­164.

Bourelly, P., and E. Manguin. 1954. Contribution of the freshwater algae from Kerguelen. Memoires de l'Institut Scientifique de Madagascar, 5, 7­58. [In French]

Brady, H.T., and H. Martin. 1979. Ross Sea region in the middle Miocene: A glimpse into the past. Science, 203, 437­438.

Bromwich, D.H., and F.M. Robasky. 1983. Recent precipitation trends over the polar ice sheets. Meteorology and Atmospheric Physics, 51, 259­274.

Burckle, L.H. 1995. Upper Neogene diatoms in Beacon Supergroup (Devonian to Jurassic) sedimentary rocks: The collapse of the collapse hypothesis. Abstracts, Pliocene Antarctic Glaciation Workshop, 19­21 April 1995, Woods Hole, Massachusetts, Woods Hole Oceanographic Institution.

Burckle, L.H. In preparation. Pliocene-Pleistocene diatoms in Paleozoic and Mesozoic igneous rocks from Antarctica cast considerable doubt upon the ice sheet collapse hypothesis. Nature.

Burckle, L.H., R.I. Gayley, M. Ram, and J.-R. Petit. 1988. Diatoms in antarctic ice cores: Some implications for the glacial history of Antarctica. Geology, 16(4), 326­329.

Burckle, L.H., and N. Potter, Jr. 1996. Pliocene-Pleistocene diatoms in Paleozoic and Mesozoic sedimentary and igneous rocks from Antarctica: A Sirius problem resolved. Geology, 24(3) 235­238.

Cassie, V. 1984. Checklist of the freshwater diatoms of New Zealand. Bibliotheca Diatomologica, 4, 1­129.

De Angelis, M., N.I. Barkov, and V.N. Petrov. 1987. Aerosol concentrations over the last climate cycle (160 kyr) from an antarctic core. Nature, 325, 318­321.

Denton, G.H., J.G. Bockheim, S.C. Wilson, and M. Stuiver. 1989. Late Wisconsin and early Holocene glacial history, inner Ross embayment, Antarctica. Quaternary Research, 31(2), 151­182.

Denton, G.H., M.L. Prentice, and L.H. Burckle. 1991. Cainozoic history of the antarctic ice sheet. In R.J. Tingey (Ed.), The geology of Antarctica. Oxford: Clarendon University Press.

Denton, G.H., M.L. Prentice, D.E. Kellogg, and T.B. Kellogg. 1984. Late Tertiary history of the antarctic ice sheet: Evidence from the Dry Valleys. Geology, 12(5), 263­267.

Drebes, G. 1974. Marine phytoplankton. Stuttgart: Georg Thieme Verlag.

Fitzgerald, P.G. 1992. Transantarctic Mountains of southern Victoria Land: The application of apatite fission track analysis to a rift shoulder uplift. Tectonics, 11(3), 634­662.

Folger, D.W. 1970. Wind transport of land-derived mineral, biogenic, and industrial matter over the North Atlantic. Deep-Sea Research, 17, 337­352.

Frenguelli, J. 1923. Diatoms of Tierra del Fuego, part 1. Annals of the Scientific Society of Argentina, 96, 14­263. [In Spanish]

Frenguelli, J., and H.A. Orlando. 1958. Diatoms and silicoflagellates of the antarctic sector of South America. Buenos Aires: Instituto Antartico Argentino.

Fritsch, F.E. 1912a. Freshwater algae in National Antarctic Expedition 1901­1904. Natural History (Zoology and Botany, London), 6, 1­60.

Fritsch, F.E. 1912b. Freshwater algae of the South Orkneys, Report on the scientific results of the voyage of S.Y. "Scotia" (Vol. 3). Edinburgh: Publisher not given.

Germain, H. 1981. Diatom flora. Paris: Editions Boubee. [In French]

Gillieson, D. 1991. Diatom stratigraphy in antarctic freshwater lakes. In D. Gillieson and S. Fitzsimmons (Eds.), Quaternary Research in Australian Antarctic (special publication 3). Canberra: Australian Defense Force Academy, Department of Geography and Oceanography, University College.

Gow, A.J. 1995. Personal communication.

Harper, M. 1995. Personal communication.

Harwood, D.M. 1986a. Diatom biostratigraphy and paleoecology and a Cenozoic history of antarctic ice sheets. (Ph.D Thesis, Ohio State University, Columbus.)

Harwood, D.M. 1986b. Recycled siliceous microfossils from the Sirius Formation. Antarctic Journal of the U.S., 21(5), 101­103.

Harwood, D.M., R.P. Scherer, and P.-N. Webb. 1989. Multiple Miocene marine productivity events in West Antarctica as recorded in upper Miocene sediments beneath the Ross Ice Shelf (site J-9). Marine Micropaleontology, 15, 91­115.

Harwood, D.M., and P.-N. Webb. 1995. The case for dynamic Cenozoic ice sheets in Antarctica. Abstracts, Pliocene Antarctic Glaciation Workshop, 19­21 April 1995, Woods Hole, Massachusetts, Woods Hole Oceanographic Institution.

Hogan, A., S. Barnard, J. Samson, and W. Winters. 1982. The transport of heat, water vapor and particulate material to the south polar plateau. Journal of Geophysical Research, 87, 4287­4292.

Hustedt, G. 1959. The diatoms of Germany, Austria, and Switzerland. Leipzig: Akademische Verlagsgesellschaft Geest and Portig K.-G. (New York: Johnson Reprint Corporation). [In German]

Karaswa, S., and H. Fukushima. 1977. Diatom flora and environmental factors in some freshwater ponds of East Ongul Island. Antarctic Record (Japan), 59, 46­54.

Kellogg, D.E. In preparation. Diatom evidence for high-frequency changes in high-elevation atmospheric circulation patterns above Antarctica.

Kellogg, D.E., and T.B. Kellogg. 1984. Nonmarine diatoms in the Sirius Formation. Antarctic Journal of the U.S., 19(5), 44­45.

Kellogg, D.E., and T.B. Kellogg. 1986. Diatom biostratigraphy of sediment cores from beneath the Ross Ice Shelf. Micropaleontology, 32(1), 74­94.

Kellogg, D.E., and T.B. Kellogg. 1987a. Diatoms of the McMurdo Ice Shelf, Antarctica: Implications for sediment and biotic reworking. Palaeogeography, Palaeoclimatology, Palaeoecology, 60, 77­96.

Kellogg, D.E., and T.B. Kellogg. 1987b. Microfossil distributions in modern Amundsen Sea sediments. Marine Micropaleontology, 12, 203­222.

Kellogg, D.E., and T.B. Kellogg. 1996. Diatoms in South Pole ice: Implications for eolian contamination of Sirius Group deposits. Geology, 24(2), 115­118.

Kellogg, D.E., M. Stuiver, T.B. Kellogg, and G.H. Denton. 1980. Nonmarine diatoms from Late Wisconsin perched deltas in Taylor Valley, Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology, 30, 157­189.

Kellogg, T.B., and D.E. Kellogg. 1981. Pleistocene sediments beneath the Ross ice shelf. Nature, 293, 130­133.

Kennett, J.P. 1995. Modern shallow marine faunas of the Antarctic: Long-term evolutionary consequences of a relatively stable, isolated, cold-water ecosystem. Abstracts, Pliocene Antarctic Glaciation Workshop, 19­21 April 1995, Woods Hole, Massachusetts, Woods Hole Oceanographic Institution.

Kennett, J.P., and D.A. Hodell. 1993. Evidence for relative climatic stability of Antarctica during the early Pliocene: A marine perspective. Geografiska Annaler, 75A, 205­220.

Kennett, J.P., and D.A. Hodell. 1995. Stability or instability of antarctic ice sheets during warm climates of the Pliocene? GSA Today, 5, 1, 10­13, 22.

Kuivinen, K.C., B.R. Koci, G.W. Holdsworth, and A.J. Gow. 1982. South Pole ice core drilling, 1981­1982. Antarctic Journal of the U.S., 17(5), 89­91.

Lavrenko, G.Y. 1966. Algae of a lake near Novolazareveskaya Station. Soviet Antarctic Expedition Information Bulletin 55/56, 6, 53­66.

Marchant, D.R., G.H. Denton, J.G. Bockheim, S.C. Wilson, and A.R. Kerr. 1994. Quaternary changes in level of the upper Taylor Glacier, Antarctica: Implications for paleoclimate and east antarctic ice sheet dynamics. Quaternary Research, 23(1), 29­43.

Marchant, D.R., G.H. Denton, D.E. Sugden, and C.C. Swisher, III. 1993. Miocene glacial stratigraphy and landscape evolution of the western Asgard Range, Antarctica. Geografiska Annaler, 75A, 303­330.

McIntosh, W.C., and T. Wilch. 1995. Applications of 40Ar/39Ar dating of volcanic ash to antarctic Neogene climate and glacial history: A review of some published and ongoing studies. Abstracts, Pliocene Antarctic Glaciation Workshop, 19­21 April 1995, Woods Hole, Massachusetts, Woods Hole Oceanographic Institution.

McKelvey, B.C., P.-N. Webb, D.M. Harwood, and M.C.G. Mabin. 1991. The Dominion Range Sirius Group: A record of the late Pliocene­early Pleistocene Beardmore Glacier. In M.R.A. Thompson, J.A. Crame, and J.W. Thompson (Eds.), Geological evolution of Antarctica. Cambridge: Cambridge University Press.

Oppenheim, D.R. 1990. A preliminary study of benthic diatoms in contrasting lake environments. In K.R. Kerry and G. Hempel (Eds.), Antarctic ecosystems: Ecological change and conservation (Proceedings of the 5th SCAR Symposium on Antarctic Biology). Berlin: Springer-Verlag.

Parish, T.R., and D.H. Bromwich. 1987. The surface windfield over the antarctic ice sheets. Nature, 328, 51­54.

Patrick, R., and C. Reimer. 1966. Diatoms of the United States. Philadelphia: Academy of Natural Sciences.

Scherer, R.P. 1991. Quaternary and Tertiary microfossils from beneath ice stream B: Evidence for a dynamic west antarctic ice sheet history. Palaeogeography, Palaeoclimatology, Palaeoecology (Global and Planetary Change Section), 90(4), 395­412.

Schmidt, R., R. Maeusbacher, and J. Mueller. 1990. Holocene diatom flora and stratigraphy from sediment cores of two antarctic lakes (King George Island). Journal of Paleolimnology, 3(1), 55­74.

Seaburg, K.G., B.C. Parker, G.W. Prescott, and L.A. Whitford. 1979. The algae of southern Victoria Land, Antarctica. Vaduz: J. Cramer.

Shaw, G.E. 1978. Particles in the air at the South Pole. Antarctic Journal of the U.S., 13(5), 194­196.

Stroeven, A.P., and M.L. Prentice. 1995. Marine diatoms in antarctic Tertiary tills: A new dataset from Mount Fleming, south Victoria Land, indicates possible transport mechanisms. Abstracts, Pliocene Antarctic Glaciation Workshop, 19­21 April 1995, Woods Hole, Massachusetts, Woods Hole Oceanographic Institution.

Stuiver, M., G.H. Denton, T.J. Hughes, and J.L. Fastook. 1981. History of the marine ice sheet in West Antarctica during the last glaciation: A working hypothesis. In G.H. Denton and T.J. Hughes (Eds.), The last great ice sheets. New York: Wiley-Interscience.

Truesdale, R.S., and T.B. Kellogg. 1979. Ross Sea diatoms: Modern assemblage distributions and their relationship to ecologic, oceanographic, and sedimentary conditions. Marine Micropaleontology, 4(1), 13­31.

van Heurck, H. 1896. A treatise on the diatomaceae. London: William Wesley and Son.

Webb, P.-N., and D.M. Harwood. 1991. Late Cenozoic glacial history of the Ross embayment, Antarctica. Quaternary Science Reviews, 10(2/3), 215­223.

Webb, P.-N., D.M. Harwood, B.C. McKelvey, J.H. Mercer, and L.D. Stott. 1984. Cenozoic marine sedimentation and ice-volume variation on the east antarctic craton. Geology, 12(5), 287­291.

West, W., and G.S. West. 1911. Freshwater algae. British Antarctic Expedition (1907-1909), 7, 263­298.

Wilch, T.L., G.H. Denton, D.R. Lux, and W.C. McIntosh. 1993a. Limited Pliocene glacier extent and surface uplift in middle Taylor Valley, Antarctica. Geografiska Annaler, 75A, 331­351.

Wilch, T.I., D.R. Lux, G.H. Denton, and W.C. McIntosh. 1993b. Minimal Pliocene­Pleistocene uplift of the dry valleys sector of the Transantarctic Mountains: A key parameter in ice-sheet reconstructions. Geology, 21(9), 841­844.

Davida E. Kellogg and Thomas B. Kellogg, Institute for Quaternary Studies and Department of Geological Sciences, University of Maine, Orono, Maine 04469

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