Return to front cover
|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|
TD pits B&D
|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).
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.
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