I Ti). W LU. I- LU GLACIER SURFACE 500 7 - w E I Z .\c&A G /GLACIER 14/Lso,v 100 BOTTOM - SEA LEVEL --- GL.. -I ] —100 rs rA 5) --

10 KM 1 B.

Figure 1. Radio-echo sounding profiles extending (A) southward from McMurdo Sound through the Wilson Piedmont and Victoria Lower Glaciers to lower Victoria Valley, and (B) northeastward from lower Wright Valley through Wright Lower and Wilson Piedmont Glaciers to McMurdo Sound. Dashed lines representing snouts of valley glaciers are projections from maps or from other radio-echo data. Some small irregularities in glacier surfaces are caused by errors in pressure record of flight recorder. Figure 2. Radio-echo sounding profile westward from McMurdo Sound through lower Ferrar and upper Taylor Glaciers to 155°E. longitude, on Victoria Land plateau.

EAST WEST

ICE SHEET 145 ibco 1 500 200 SEA LEVEL--,

-400 HIS SEEM " -200 KM ncrth—south faults bounding the eastern side of the Antarctic geologic reports and maps mountains may be indicated by steep breaks in slope occurring in the bottom trace of the profiles transect- CAMPBELL CRADDOCK in the Wilson Piedmont area (figs. 1A and 1B). Department of Geology and Geophysics Work described in this paper was undertaken at the University of Wisconsin, Madison Scott Polar Research Institute, Cambridge, England. Work has continued this year on bringing to publi- References cation the results of eight seasons of geologic study in Ca kin, P. E. In press. Glacial geology of the Victoria Valley parts of West Antarctica. Recent effort has focused on system, southern Victoria Land, Antarctica. Antarctic Re- the question of the age and nature of ancient glacia- search Series. tion in the Jones Mountains. Ten new potassium-ar- Ca kin, P. E., R. E. Behling, and C. Bull. 1970. Glacial istory of Wright Valley, southern Victoria Land, Ant- gon ages obtained by Professor R. L. Armstrong of rctica. Antarctic Journal of the U.S., V( I) : 22-27. Yale University indicate that glaciation was under Crary, A. P. 1963. Results of United States traverses in way at least 7 million years ago. A week of study of ast Antarctica, 1958-1961. ICY Glaciological Report, 7. 144 p. the subglacially erupted volcanic table mountains of De ton, G. H., R. L. Armstrong, and M. Stuiver. 1970. northeastern Iceland, in company with Professors MLate Cenozoic glaciation in Antarctica: the record in the Rutford (University of South Dakota) and LeMasur- cMurdo Sound region. Antarctic Journal of the U.S., ier (University of Colorado), revealed strong similari- (1): 15-21. ties to the morphology and rock types of the Jones Drewry, D. J . In press. Subglacial morphology between the ](ransantarctic Mountains and the South Pole. In: Ant- Mountains. The evidence for Tertiary continental gla- arctic Geology and Geophysics. Oslo, Universitetsforlaget. ciation in the Jones Mountains is summarized in a Robin, G. de Q . , S. Evans, D. J . Drewry, C. H. Harrison, forthcoming paper (Rutford et al., 1970). and D. L. Petrie. 1970. Radio-echo sounding of the antarctic ice sheet. Antarctic Journal of the U.S., V(6) Since 1964 I have worked as a contributor to and 229-232. coeditor of a folio of maps portraying the state of

September—October 1971 209 knowledge of antarctic geology. Folio 12 of the Ant- Craddock, C. 1970b. Antarctic geology and Gondwana- arctic Map Folio Series has now been published by the land. Bulletin of the Atomic Scientists, 26(10): 33-39. Craddock, C. 1970c. Antarctic geology in Oslo. Geotimes, American Geographical Society with support from the 15(9): 20-22. National Science Foundation (Bushnell and Grad- Craddock, C. (ed.). 1970d. Earth Sciences Investigations dock, 1970). It can be obtained for $12 from the in the U.S. Antarctic Research Program for the Period American Geographical Society, Broadway at 156th July 1, 1969, to June 30, 1970. National Academy of Sci- Street, New York, New York 10032. The folio con- ences. 31 p. Rutford, R. H., C. Craddock, R. L. Armstrong, and C. M. tains (1) 18 regional geologic maps at a scale of White. 1970. Tertiary glaciation in the Jones Moun- 1:1,000,000 or larger, (2) maps of the entire conti- tains, Antarctica. Geological Society of America. Abstracts nent at a smaller scale portraying geology, tectonics, with Programs, 2(7) : 670-671. In press, Oslo, Univek- fossil and age determination localities, and geo- sitetsforlaget. morphic features, and (3) a map of Gondwanaland. The completion of Folio 12 made possible a new in- terpretation of the tectonics of Antarctica (Craddock, 1970a) and new insight into the place of Antarctica in the former protocontinent Gondwanaland (Craddock, Mummified seals 1970b). of southern Victoria Land There long has been a need for a geologic map of Antarctica at a scale of 1:5,000,000 (a standard scale WAKEFIELD DORT, JR. in general usage elsewhere) to facilitate comparisons Department of Geology between the continents. Although they were published The University of Kansas at a smaller scale, the maps of the entire continent in One of the more puzzling of the many interesting Folio 12 were compiled on the scale of 1:5,000,000 to features of the dry valleys of southern Victoria Land allow the subsequent preparation of such a map by is the presence there of numerous seal bodies well pre- combining the data on the individual maps. A great served by desiccation or mummification in the cold, deal of new information on antarctic geology has dry environment (see cover). These unusual remains become available during the past year, especially at were first discovered when land exploration of the re- the 1970 Oslo symposium, and I have revised the map gion commenced with Captain Scotts first antarctic to include, wherever feasible, all new data available to expedition of 1901-1904. Since 1957, literally dozens me in May 1971. The finished map will include geo- of bodies have been observed by the many parties that logic units, structural data, fossil and age determina- have undertaken field studies in the area. tion localities, bathymetric and ice-cap surface con- Available information is not sufficiently detailed to tours, and references to new sources beyond those permit computation of an accurate total of the num- cited in Folio 12. This map is now in the final draft- ber of carcasses present. A minimum of 210 seal bod- ing stage and should be published shortly. ies have been observed in the three main dry-valley In my role as a member of the Committee on Polar systems; an additional 70 reported sightings may, Research and U.S. member of the Scientific Commit- least in part, represent duplication of discoveries. tee on Antarctic Research Working Group on Geol- However, the University of Kansas field parties re- ogy, during the past year I have (1) assisted in prepa- corded the locations of 106 carcasses in Taylor Valley ration for the SCAR/ International Union of Geologi- alone. Additional finds were reported from the Ferrar cal Sciences symposium on antarctic geology and Glacier by members of the Scott expedition and from solid-earth geophysics held in Oslo in August 1970, (2) smaller ice-free coastal valleys east of the Royal prepared a review of the events of that symposium Society Range by several parties, especially those of (Craddock, 1970c), (3) organized and chaired a sym- Péwé, who discovered 20 carcasses in and near G r- posium on antarctic geology at the 1970 annual meet- wood Valley. ing of the Geological Society of America in Milwau- In the Victoria, Wright, and Taylor Valley syster is, kee, (4) supervised the preparation of an annual re- mummified seals have been found as far as 66 km n- port to SCAR on USARP earth sciences activities land from McMurdo Sound. Most bodies are on or (Craddock, 1970d), and (5) initiated the compilation near the valley floors, especially against easte ly of a lexicon of stratigraphic names introduced by facing escarpments or other topographic situaticns members of U.S. antarctic expeditions. that form cul de sacs impeding easy westward trael. A few seals, however, succeeded in climbing steep References slopes or even isolated peaks before dying at elevations Bushnell, V. C., and C. Craddock (eds.). 1970. Geologic ranging up to 1,200 in sea level. maps of Antarctica. Antarctic Map Folio Series, 12. The occurrence of the remains of seal bodies at in- Craddock, C. 1970a. Antarctic tectonics. Geological So- land locations in southern Victoria Land is not dupli- ciety of America. Abstracts with Programs, 2(7): 527. In press, Oslo, Universitetsforlaget. cated elsewhere in Antarctica. Carcasses observed by

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