Late Cenozoic Glaciation in has it ever partly or wholly disappeared? Has the Ice Sheet undergone changes in area and volume and, if Antarctica: The Record in the so, were the changes contemporaneous with world- wide Quaternary glaciations? Has the Antarctic Ice McMurdo Sound Region Sheet experienced catastrophic surges (Wilson, 1964), or has it merely reacted passively to sea-level changes induced by Northern Hemisphere Quaternary ice GEORGE H. DENTON sheets (Hollin, 1962), or has it fluctuated out of phase Department of Geological Sciences with worldwide Quaternary glaciations as a result of University of Maine increased accumulation during interglacial ages (Scott, 1905; Markov, 1969)? Will the future be- RICHARD L. ARMSTRONG havior of the Ice Sheet involve large-scale surges, Department of Geology and Geophysics widespread melting, continuation of present growth, Yale University or stability? Finally, have any areas remained free of and ice to serve as possible biologic refugia throughout the long history of antarctic refrigeration? MINZE STUIVER Some of these questions can be answered partially Department of Geology by examining the glacial history of ice-free areas in University of Washington the McMurdo Sound region of southern Victoria Land. Here is preserved a unique and datable record of the history of the three major glacier systems in the Introduction region (Fig. 1). First, the huge ice sheet of East Ant- arctica is dammed west of the Transantarctic Moun- More than 50 years of antarctic research have pro- tains, which in this region trend nearly north-south vided numerous observations and diverse ideas, along along the coast. Taylor and Wright Upper Glaciers, with many unanswered questions about the long his- which are small tongues of the ice sheet, spill over tory of antarctic glaciation. What is the history of the bedrock thresholds and occupy the western ends of Antarctic Ice Sheet? When and why did it form? Has Taylor and Wright Valleys—glacially carved valleys the Ice Sheet existed continuously since its origin, or that cross the mountains from the ice sheet on the 1700 IQ 0

770

I 8°

Figure 1. Index map of the McMurdo Sound region, southern Victoria Land, Antarctica.

January-February 1970 15 west to McMurdo Sound on the east. Second, the Valley. The eastern half of the valley is now free of Ross Ice Shelf floats on the surface of the Ross Sea to ice except for small alpine glaciers on the valley walls. the east of the Transantarctic Mountains. The Ross However, on at least five occasions in the past, in- Ice Shelf is nourished by direct accumulation of snow, creases in the surface level of the ice sheet in East by discharge both from the ice sheet in West Antarc- Antarctica have caused major advances of Taylor tica and from outlet glaciers draining the ice sheet in Glacier (Fig. 3) . The drift sheets or erosional fea- East Antarctica, and perhaps by bottom freezing. tures of all five Taylor advances are related to the ice Finally, independent alpine glaciers occur throughout sheet in East Antarctica and are not associated with the Transantarctic Mountains in the McMurdo local alpine glaciers or intermontane ice sheets. Sound area. A few of these glaciers are shown in During Taylor Glaciation (s) V, which probably Fig. 1. was multiple, ice tongues reached McMurdo Sound Past fluctuations of the three major glacier systems and carved all the major features of glacial erosion of the McMurdo Sound region were not synchronous. in the valley, including truncated spurs, riegels, hang- Therefore, the history and chronology of each system ing valleys, and over-steepened walls. Taylor and must be considered independently, as indicated in Fig. Wright Valleys thus attained their present profiles 2. In the McMurdo Sound region, changes in surface during Taylor Glaciation (s) V. Subsequent glacia- level of the ice sheet in East Antarctica were recorded tions of Taylor Valley have caused very little erosion, by advances and recessions of Taylor Glacier and suggesting that the ice tongues that carved the valleys Wright Upper Glacier. In the following, these events were wet-based, whereas subsequent ice tongues were in Taylor Valley are termed Taylor Glaciations. dry-based. Expansions of the Ross Ice Shelf into ice sheets, which Ice of Taylor Glaciations V, IV, and III also were largely grounded on the floor of the Ross Sea, reached McMurdo Sound. However, the advance of are termed Ross Sea Glaciations .2 Likewise, expan- Taylor Glaciation II was relatively minor and ex- sions of alpine glaciers are called Alpine Glaciations. tended only about 4 km downvalley from the present The advances of each glacier system are numbered terminus of Taylor Glacier. Taylor Glaciation I, as from youngest to oldest. All the terminology, includ- will be detailed in a later section, is current; and Tay- ing the numbering system, is provisional and will be lor Glacier, Wright Upper Glacier, and the edge of replaced by formal geologic nomenclature on com- the ice sheet in this area now occupy their maximum pletion of the research. positions since before the beginning of the Wisconsin The absence of good stratigraphic sections of gla- (Würm) Glaciation as defined elsewhere in the world cial deposits requires that identification of glacial (Denton and Armstrong, 1968; Denton et al., 1969). sequences be based on surface deposits. Thus, the se- Considerable ice recession separated each Taylor quences record only successively less extensive ad- Glaciation. Lava flows deposited in Taylor Valley be- vances, and some glaciations undoubtedly were not tween Glaciations V and IV provide K/Ar dates that identified explicitly. range from 2.7 to 3.5 m.y.; volcanic cones in a similar stratigraphic position in nearby Wright Valley are Glacial Geology and Chronology about 3.7 m.y. old. Lava flows separating drifts of Taylor Glaciations IV and III are between 1.6 and Taylor Glacier drains the ice sheet in East Ant- 2.1 m.y. old. arctica and, at the present time, spills over a bedrock On at least four occasions, the Ross Ice Shelf ex- threshold to occupy the western 70 km of Taylor panded into an ice sheet grounded on the floor of the Ross Sea (Fig. 4). During these Ross Glaciations, ice sheets in the Ross Sea and McMurdo Sound reached Previously, the term "glacier episode" had been used high on the flanks of Mount Discovery, Brown Penin- (Denton and Armstrong, 1968; Denton et al., 1969) in def- erence to the definition of the American Commission on sula, and Black, White, and Ross Islands. Glacier Stratigraphic Nomenclature (1961, P. 660), which restricted tongues from these ice sheets pushed westward up "glaciation" to a climatic episode. This definition does not Taylor Valley and the valleys fronting the Royal So- apply in Antarctica, where fluctuations of glaciers were not ciety Range, leaving well-preserved moraines on the related to climate in a simple manner. Therefore, as defined here, a "glaciation" was an event during which large glaciers valley floors and along the coast. advanced, attained a maximum extent, and receded. This definition removes all the climatic connotations inherent in the definition of the American Commission on Stratigraphic Nomenclature (1961, p. 660). 2 Previously, these were called "Ross Glacial Episodes" Péwé (1960) was the first to discover multiple glaciation (Denton and Armstrong, 1968; Denton et al., 1969). "Ross in Antarctica and to describe advances of Taylor Glacier. Sea Glaciations" is used here because of the definition given Similar advances have been recognized in Wright Valley in the first footnote and because the term "Ross" duplicates (Bull et al., 1962; Nichols, 1961) and in the Victoria Valley New Zealand glacial terminology. system (Calkin, 1964).

16 ANTARCTIC JOURNAL

Taylor Glaciations I Ross Sea Glaciations (Ice Sheet in East Antarctica West of I Alpine Glaciations Taylor and Wright Valleys) I (Ross Ice Shelf) 4450 yrs. B.P. (L-627; Marble Point) 5900 yrs. B.P. (L-462; Hobbs Glacier )2 6100 yrs. B.P. (Y-2401; Hobbs Glacier) Taylor I 9490 yrs. B.P. (Y-2399; Hobbs Glacier) Alpine I

12,200 yrs. B. P. (1-3019; Hobbs Glacier) Ross I 34,800 yrs. B.P. (no laboratory number given; Cape Barne)4 Alpine II >47,000 yrs. B.P. (Y-2641; Cape Barne; same locality as sample dated 34,800 K/Ar dates; 2.1 to 0.4 m.y. yrs. B.P.) (Walcott Glacier area) >49,000 yrs. B.P. (Y-2642; Cape Barne) Ross II Taylor II Ross III Ross IV Taylor III K/Ar dates; 3.1 to 1.2 my. (Walcott Glacier area) K/Ar dates; 1.6 to 2.1 m.y. (Taylor Valley) K/Ar dates; 2.1 my. (Taylor Valley)

Taylor IV Alpine III

K/Ar dates; 2.7 to 3.5 my. (Taylor K/Ar dates; 3.5 my. (Taylor Valley) Valley) and 3.7 my. (Wright Valley)

Taylor(s) V

1 Nichols (lOGS, p. 471) ; Olson and Broecker (1961, P 150). The C" date given in the chart and text is corrected. The uncorrected date Is 3650±150 yrs. B.P. (L-027). (1961). 3 Black and Bowser (1969). Wilson (In press).

Figure 2. Schematic correlation chart and chronology of glacial events in the McMurdo Sound region. The K/Ar dates given here are rough averages of numerous age determinations made over a period of several years. The dating is still in progress; thus, the averages given here and in previous papers have changed and will change slightly as new dates become available.

Several K/Ar and C 14 dates place limits on the drift of Ross Sea Glaciation IV, thus placing a rnaxi- ages of Ross Sea Glaciations. In the vicinity of Wal- inum age on all recognized Ross Sea Glaciations. At cott Glacier, lava flows dated at 1.2 ln.y. underlie two localities on Cape Barne, Ross Island (Deben- ham, 1921; Wilson, in press), raised marine beds con- taining numerous shells occur immediately beneath C4 dates in Antarctica must be interpreted with caution. erratics or drift presumably deposited during Ross The base for the age determinations given here is 0.95 per- Sea Glaciation I. On this stratigraphic basis, the ma- cent of the C14 activity of oxalic acid. Because the waters of rine beds are assigned to the interval between Ross McMurdo Sound are deficient in C 14, dates calculated in this manner are too old and must he adjusted by 600 to 1300 Sea Glaciations I and II, when McMurdo Sound was years (Broecker and Olson, 1961, p. 200; Marini et al., free of grounded glacier ice. However, the shells 1967). Likewise, samples of algae from hard-water lakes may possibly date from an earlier interval of ice also may be too old in some cases; this problem is not re- recession. Shells from one of the marine deposits, stricted to Antarctica but is encountered in numerous areas throughout the world. Unless otherwise indicated, the dates located at 59-63 m above the present sea level, gave given here are not corrected. an age of >49,000 yrs. B.P. (Y-2642). Shells from

January-February 1970 17

163° 162°

1 0 5 10 TKILOMETERS / -. -- 77045 77045 N. — Taylor Glacier Mary GI - / - nR

- .-i- mcr. GI. Matterhorn 6!.

ROSS SEA DRIFT TAYLOR DRIFT Canada GL McMurdo (till) llhlllllUI(strandlines I Current (Taylor 61.) Sound & lacustrine sediment ) It 31 (till) Itt - (till) (till) 77°30 77°30 163° 162°

Figure 3. Schematic map showing some of the major glacial units in Taylor Valley. Many units, including drift deposited by alpine glaciers and by older Ross ice sheets, cannot be included at this scale.

1580 70°

I ROSS SEA I Mt Discovery cr1 C I Z ( (1) Black Walcott M ICE White 61 z —I —1 Brow IV Peninsula Z 780 780 MiersGl. SHEET Hobbs 61. — (1) Blue 61 I)

GIocierier

Cope Borne Ross Island Valley Cona da Gl el z iacIer McMurdo Marble Pt victorioValley Sound System CA

00 20 30 40 5060 KILOMETERS D r C = C A 770 77° 170° 158°

Figure 4. Schematic map showing the extent of the Ross Sea I ice sheet. In places, the thickness of this ice sheet exceeded 1000 m. The present-day configuration is shown for the ice sheet in East Antarctica.

18 ANTARCTIC JOURNAL the other deposit, located at 28.5 to 31.7 m above sheets pushed westward up Taylor Valley to the vicin- present sea level, gave conflicting results. A. T. Wil- ity of the present Canada Glacier (Fig. 3). These son (in press) reports a date of 34,800± 2300 yrs. tongues dammed large lakes in Taylor Valley. The B.P. (no laboratory number given) for these shells. resulting strandlines are common throughout the However, another sample collected by the writers eastern half of the valley; those of Ross Sea I age from the same locality gave an age of >47,000 yrs. occur up to about 310 m in altitude and those of Ross B.P. (Y-2641). Sea II age reach 400 m. Subsequent to recession of Several C 14 dates afford minimum ages of reces- Ross Sea I ice and concomitant draining of lake sion of the Ross Sea I ice sheet from coastal areas water from Taylor Valley, Taylor Glacier advanced back into McMurdo Sound. Most of these samples across Ross Sea I strandlines, across moraines de- consist of fresh-water algae buried in, or resting on, posited by alpine glaciers during the Ross Sea TI/I ice-cored moraines deposited along the west coast of interval of ice recession, and across Ross Sea II McMurdo Sound by the Ross Sea I ice sheet. The strandlines (Fig. 3). The geometric relation of Taylor algae originally grew in small kettle lakes, which Glacier to these features shows that the glacier pres- formed on ice-cored moraine and which were de- ently occupies its maximum position since before Ross stroyed by shifting of moraine due to melting of ice Sea Glaciation II. Second, a vast difference in weath - cores. In the area of the present Hobbs Glacier, algae ering exists between Ross Sea I drift and Taylor II samples provide minimum dates for initial retreat drift, which borders Taylor Glacier. Granite boulders from the outer portion of Ross Sea I drift of 5900 on Ross Sea I glacial deposits are very little weath- yrs. B.P. (L-462) (Olson and Broecker, 1961, p. 149; ered. In sharp contrast, granite boulders on Taylor II Péwé, 1960, p. 512), 6100 yrs. B.P. (Y-2401), and deposits immediately bordering Taylor Glacier are in 9490 yrs. B.P. (Y-2399). Another C14 date from this an advanced state of cavernous weathering and some area indicates that ice had receded from the present are weathered to ground level. Highly weathered drift coastline prior to 3930 yrs. B.P. (Y-2401). An algae also borders Wright Upper Glacier and the adjoining sample resting on Ross Sea I drift at an altitude of edge of the ice sheet where it abuts against the Trans- 65 m on Cape Barrie, Ross Island, gives a minimum antarctic Mountains. The sharp weathering difference date for ice recession of 2760 yrs. B.P. (Y-2623). between Ross Sea and Taylor drifts indicates that Finally, based on the corrected age of an elephant these ice bodies presently occupy their maximum po- seal buried in a raised beach at Marble Point, ice sitions since before the Ross Sea Glaciation I. These recession had proceeded sufficiently for seasonal open data are consistent and, taken as a whole, indicate water to exist there prior to 4450 yrs. B.P. (L-627) that Taylor Glacier, Wright Upper Glacier, and the (Nichols, 1968, p. 471). adjoining ice sheet were smaller than at present dur- The ages and distribution of mummified seals rest- ing Ross Sea I time, that they have since expanded, ing on ice-free surfaces in the McMurdo Sound re- and that they now occupy their maximum positions gion give information about the withdrawal of the since before Ross Sea Glaciations I and II. In view Ross Sea I ice sheet from McMurdo Sound, since of the C14 ages of young Ross Sea events, Ross Sea nearby open water was necessary for seal immigra- Glaciation II must have occurred during or prior to tion. The corrected ages of the oldest mummified seals the Early Wisconsin (Wünn) Glaciation as defined in the ice-free areas range from about 900 yrs. B.P. to elsewhere in the world. Thus it follows that the ice about 3000 yrs. B.P. (Barwick and Balham, 1967; sheet west of Taylor and Wright Valleys probably Siegel and Dort, 1968). Furthennore, mummified occupies its maximum surface level since before Wis- seals are common in ice-free areas only as far south consin (Würrn) time. These data are in complete ac- as Miers Valley, which fronts the Royal Society cord with the conclusion previously reached by Wil- Range and trends eastward from Miers Glacier to the son (1967, p. 157) from geochemical data that Taylor Ross Ice Shelf. Extensive search by the writers re- and Wright Upper Glaciers did not advance eastward vealed only one mummified seal south of Miers Val- through the valleys during Wisconsin (Wiirrn) time. ley. This distribution seems to rule out a recent re- The fluctuations of alpine glaciers have been dis- treat of the Ross Ice Shelf, for such retreat would cussed by Denton and others (1969). All three recog- have opened ice-free areas south of Miers Valley to nized alpine glacier fluctuations were minor. The extensive seal immigration. youngest two occurred in opposite phase to Ross Sea Two parameters relate recent Ross Sea and Taylor Glaciations, probably reflecting the presence or ab- Glaciations, and allow comparison of their relative sence of a precipitation source in the Ross Sea due to chronologies. First, the present tongue of Taylor Gla- opening or closing of that water body by ice sheets. cier is in physical contact with deposits of Ross Sea I In addition, a slight change in shape of alpine glaciers and Ross Sea II ages, which in turn are related to the has occurred within the last several thousand years, C14 dates mentioned above. During Ross Sea II and and may record a relatively recent change from a Ross Sea I Glaciations, ice tongues from Ross Sea ice wanner, moister climate to a cooler, drier climate.

January-February 1970 19 Conclusions system of the ice sheet in East Antarctica (Giovinetto et al., 1966). Radiometric dates and geologic rela- tions indicate, in fact, that the ice sheet in this area 1. The huge ice sheet in East Antarctica had at- is now at its maximum height since before the Wis- tained a full-bodied stage more than 4 m.y. ago. The consin (Würm) Glaciation as defined elsewhere in buildup of this ice sheet and the accompanying fall the world (Denton et al., 1969). The recorded of sea level through about 55 m thus occurred during changes in surface level of the ice sheet in East or before the Pliocene Epoch. Rutford and others Antarctica were not synchronous with worldwide (1968) have shown that a large ice sheet occupied glaciations. much of West Antarctica by the late Miocene. Since 3. All four recognized Ross Sea Glaciations were it was largely grounded below sea level, this ice sheet confined to the last 1.2 m.y. The withdrawal phase in West Antarctica must have been preceded by ice of Ross Sea Glaciation I coincided closely with the shelves, which in turn required polar conditions and rapid rise of sea level during Late Wisconsin (Würm) snowlines very close to sea level. Considering the con- time. The most probable explanation for this apparent ditions in West Antarctica, it may be reasonable to correlation is provided by Hollins (1962) model of assume that an ice sheet in East Antarctica also ex- alternate grounding and floating of the Ross Ice isted during late Miocene time, especially in view of Shelf due to sea-level changes caused by Northern the probable long history of glaciation that occurred Hemisphere ice sheets. It is unlikely that the fluctua- in Taylor and Wright Valleys prior to 4 m.y. ago. tions were climatically controlled, because alpine Supporting evidence for the existence of late Miocene glaciers in the area diminished in size during Ross ice sheets in polar regions is given by a plot of Ter- Sea Glaciations. A third alternative, which is un- tiary sea level, which shows that eustatic sea level likely but which cannot be dismissed at the present began a rapid decline during the Miocene (Tanner, time, is that ice surges from West Antarctica caused 1968). Finally, data from deep-sea sediment cores in- Ross Sea Glaciations. dicate that calving glacier ice has existed in Antarc- In addition to the major Ross Sea Glaciations, tica continuously for more than 5 m.y. without major which were not synchronous with surface-level intergiacials (Goodell et al., 1968). Whether large glaciers existed in Antarctica prior changes of the ice sheet in East Antarctica, minor to the Miocene remains an open question. Tertiary fluctuations of the Ross Sea Shelf may have resulted sea-level data provide no evidence for polar ice sheets from variations in discharge of outlet glaciers which prior to the Miocene (Tanner, 1968). Furthermore, drain into the Ross Ice Shelf from East Antarctica. Australia and East Antarctica were contiguous during Such discharge variations could have resulted from the early Tertiary. About 40 m.y. ago, the continents the surface-level changes of the ice sheet in East Ant- separated, and sea-floor spreading has since moved arctica recorded by Taylor Glaciations. them to their present positions. Lack of evidence for 4. Extensive ice-free areas have existed in the glaciation in the early Tertiary stratigraphic sections McMurdo Sound region throughout the last 4 m.y., of southern Australia suggests that the East Antarctic- and perhaps throughout the long history of Cenozoic Australian land mass did not support large ice sheets glaciation in Antarctica. These ice-free areas may prior to about 40 m.y. ago. In accord with this, Adie have served as biologic refugia. (1964), Cranwell and others (1960), McIntyre and Acknowledgements. The field work reported here Wilson (1966), and Wilson (1967) have reported was carried out during the austral summers of 1967- temperate floras and faunas in rocks of Eocene, Ol- 1968 and 1968-1969 under NSF grants GA-1 156 and igocene, and early Miocene age on the Antarctic Pen- GA-4034 to the American Geographical Society and insula and in the Ross Sea area. On the other hand, GA-1157 to Yale University. The K/Ar dating was the presence of quartz grains with glacial surface tex- done by Armstrong under NSF GA-1 157; the Yale tures in Eocene sediments from deep-sea cores taken C14 dates were done by Stuiver with NSF support. in the southern oceans suggests that glaciers may have Montague Alford and Wibj3rn Karlén assisted in the existed on Antarctica during the early Tertiary field work, and Paul N. Taylor assisted in the K/Ar (Geitzenauer et al., 1968). Whether these quartz dating laboratory. Discussions with Robert L. Nichols, grains represent local calving glaciers in coastal Parker E. Calkin, and A. T. Wilson provided numer- mountains, or whether they represent large ice sheets, ous insights into the glacial history of the McMurdo is unknown. Sound region. 2. The ice sheet to the west of Taylor and Wright Valleys in East Antarctica has undergone several changes in surface level during the last 4 m.y. The References latest increase in level is current, in accord with the Adie, R. J., 1964. Geologic history. In: Antarctic Research present large positive mass budgets for this drainage Butterworths, London, p. 118-162.

20 ANTARCTIC JOURNAL American Commission on Stratigraphic Nomenclature. 1961. Olson, E. A. and W. S. Broecker. 1961. Lamont natural Code of stratigraphic nomenclature. American Association radiocarbon measurements VII. Radiocarbon, 3: 141-175. of Petroleum Geologists. Bulletin, 45: 645-665. Péwé, T. L. 1960. Multiple glaciation in the McMurdo Barwick, R. E. and R. W. Balham. 1967. Mummified seal Sound region, Antarctica; a progress report. Journal of carcasses in a deglaciated region of south Victoria Land, Geology, 68: 498-514. Antarctica. Tuatara, 15: 165-180. Rutford, R. H., C. Craddock, and T. W. Bastien. 1968. Late Black, R. F. and C. J . Bowser. 1969. Salts and associated Tertiary glaciation and sea-level changes in Antarctica. phenomena of the termini of the Hobbs and Taylor Gla- Palaeogeography, Palaeo climatology, Palaeoecology, 5: ciers, Victoria Land, Antarctica. International Union of (1) 15-39. Geology and Geophysics. Commission on Snow and Ice. Publication 79: 226-238. Scott, R. F. 1905. Results of the National Antarctic Expedi- tion, I. Geographical Journal, 25: 353-372. Broecker, W. S. and E. A. Olson. 1961. Lamont radiocarbon Siegel, F. R. measurements VIII. and W. Dort, Jr. 1968. Mirabilite and asso- Radiocarbon, 3: 176-204. ciated seal bones, southern Victoria Land, Antarctica. Bull, C., B. C. McKelvey, and P. N. Webb. 1962. Quater- Antarctic Journal of the U.S., III (5) : 173-175. nary glaciations in southern Victoria Land, Antarctica. Tanner, W. F. 1968. Tertiary Sea Level Symposium: Journal of Glaciology, 4(31): 63-78. In- troduction. Pala eogeograp hy, Palaeoclimatology, Palaeoe- Calkin, P. E. 1964. Geomorphology and Glacial Geology of cology, 5 (1): 7-14. the Victoria Valley System, Southern Victoria Land, Ant- arctica. Ohio State University. Institute of Polar Studies. Wilson, A. T. 1964. Origin of ice ages: an ice shelf theory Report no. 10. 66 p. for Pleistocene glaciation. Nature, 201: 147-149. Wilson, A. T. 1967. The lakes of the McMurdo dry valleys. Cranwell, L. M., H. J. Harrington, and I. G. Speden. 1960. Lower Tertiary microfossils from McMurdo Sound, Ant- Tuatara, 15: 152-164. arctica. Nature, 186: 700-702. Wilson, A. T. In press. Radiocarbon age of a raised marine Debenham, F. 1921. Recent and local deposits of McMurdo deposit on Cape Barne, Ross Island, Antarctica. Sound region. British Antarctic (Terra Nova) Expedition. Wilson, G. J. 1967. Some new species of lower Tertiary dino- Natural History Reports. Geology, 1: 63-100. flagellates from McMurdo Sound, Antarctica. New Zea- land Journal of Botany, Denton, G. H. and R. L. Armstrong. 1968. Glacial geology 5 (1): 57-83. and chronology of the McMurdo Sound region. Antarctic Journal of the U.S., III (4): 99-101. Denton, G. H., R. L. Armstrong, and M. Stuiver. 1969. Histoire glaciaire et chronologie de la region du detroit de McMurdo, sud de la Terre Victoria, Antarctide; note préliminaire. Revue de Géographie Physique et de Géol- ogie Dynamique, 11: 265-278. Geitzenauer, K. R., S. V. Margolis, and D. S. Edwards. 1968. Evidence consistent with Eocene glaciation in a South Pacific deep-sea sedimentary core. Earth and Plane- tary Science Letters, 4 (2): 173-177. Giovinetto, M. B., E. S. Robinson, and C. W. M. Swithin- bank. 1966. The regime of the western part of the Ross Ice Shelf drainage system. Journal of Glaciology, 6 (43): 55-68. Antarctic Journal: Goodell, H. G., N. 0. Watkins, T. T. Mather, and S. Koster. 1968. The antarctic glacial history recorded in Subscription Cost Increased sediments of the Southern Ocean. Pala eogeograp hy, Pa- laeoclimatology, Palaeoecology, 5 (1): 41-62. As of January 1, 1970, the Government Printing Hollin, J. T. 1962. On the glacial history of Antarctica. Office has increased the subscription cost for the Journal of Glaciology, Ant- 4 (32) : 173-195. arctic Journal to $3.50 in the U.S.A. and Canada and Marini, M. A., M. F. Orr, and E. L. Coe. 1967. Surviving $4.50 elsewhere. macromolecules in antarctic seal mummies. Antarctic Journal of the U.S., 11(5): 190-191. Markov, K. K. 1969. The Pleistocene history of Antarctica. In: The Periglacial Environment. McGill-Queens Uni- Back Issues of versity Press, Canada, p. 263-269. McIntyre, 0. J. and G. J. Wilson. 1966. Preliminary palyn- Antarctic Journal ology of some antarctic Tertiary erratics. New Zealand Journal of Botany, 4: 315-321. A limited number of copies of the following back Nichols, R. L. 1961. Multiple glaciation in the Wright Val- issues of the Antarctic Journal are available for free ley, McMurdo Sound, Antarctica. Tenth Pacific Science distribution on request to the Editor: Congress. Abstracts of Papers Presented, p. 317. Vol. 11(1967), Nos. 3 and 6. Nichols, R. L. 1968. Coastal geomorphology, McMurdo Sound, Antarctica. Journal of Glaciology, 7 (51): 449- Vol. III (1968), Nos. 1,2,3,4,5, and 6. 478. Vol. IV (1969), Nos. 2, 3, and 5.

January-February 1970 21