pop-up recorders to measure bottom currents at if at all. (2) The eastern side of the plateau is nor- strategic locations. The Massachusetts Institute of mally faulted and very steep and appears to be a Technology geochemistry program required five large mirror-image of Broken Ridge (to the north) but samples of sea water in the deep ocean basins near is a much more complicated structure. (3) A ridge the Kerguelen Islands and near Australia. spur northeast of the Kerguelen Islands was pre- Owing to equipment malfunctions (now repaired) viously unreported and has an important effect on the sonobuoy program obtained only poor to fair bottom water circulation. results. Pack ice and limited time prevented the The sediments on the plateau and its flanks are oceanographers from obtaining water samples near mostly 1 to 2 km thick. Slump structures and a sedi- the Amery Ice Shelf. All other objectives were ment ridge exist on the eastern side. Basement veloc- achieved satisfactorily. ities on the plateau are typically 5.0 to 5.5 km per Preliminary results are not yet available from the sec. Normal faulting within the plateau massif is station work, which requires a good deal of analysis. complex and includes repetitive basin-and-range However, underway geophysical investigations re- structures and numerous graben-horst systems. There vealed numerous significant bottom features at vari- is evidence that much of the plateau has undergone ance with the existing bathymetry: (1) Gribb Bank wave-base erosion and that it has subsided about does not exist in its plotted position (61 30 S. 88°E.), 1,300 in the erosion.
Track of USNS Eltanin Cruise 47. Numbers show selected station locations.
Geological investigations in the Queen Maud Mountains
DAVID H. ELLIOT and DONALD A. COATES Mountains. The continuing program called for (1) data collection for 1:250,000 reconnaissance geologi- cal mapping of the Queen Maud Mountains, Institute of Polar Studies regional correlation and stratigraphic study of the The Ohio State University Beacon sequence, (3) regional studies of the baseme t rocks, (4) investigation of the late Cenozoic glacil deposits, and (5) the search for more vertebrae The success of the 1969-1970 field season in the fossils. Beardmore Glacier area (Elliot, 1970) provided a The scientific staff ranged from eight to 14 duririg consid rable stimulus to the 1970-1971 field program the season. Ten geologists from The Ohio State Urü- of the Institute of Polar Studies in the Queen Maud versity and one from the University of Wisconsin car-
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ned out geological and geophysical programs. The crusty type which develops in areas of little wind. search for vertebrate fossils was conducted by verte- Parts of the surface will support a man, but other brate paleontologists from the University of California parts will let him break through and drop 20 to at Berkeley and The American Museum of Natural 25 cm to the next crusty layer. The LC-130 planes History, New York. James Kitching, a vertebrate always break through the top surface and pack the paleontologist from the Bernard Price Institute for snow beneath. Probing for crevasses is difficult because Palaeontological Research, University of the Wit- crusty layers beneath the surface stop the probe even watersrand, Johannesburg, South Africa, participated in snow bridges within crevasses. Light winds at the as an exchange scientist with the U.S. Antarctic Re- McGregor campsite made helicopter maintenance and search Program. His skill and knowledge of the South other camp work far easier than it was at Coalsack African Triassic vertebrate faunas were invaluable Bluff the previous year and at the Amundsen Camp assets to the expedition. The scientists were supported later. in the field by 16 officers and men of the VXE-6 Although investigations from the McGregor Glacier helicopter detachment and six men from Antarctic camp were principally in the Shackleton and Ramsey Support Activities of the U.S. Navy. Glacier areas, geologists worked at points as far dis- tant as the Dominion Range at the head of the Camps at McGregor and Amundsen Glaciers Beardmore Glacier and Mount Patrick near the mouth of the Beardmore. The helicopters flew a The first camp, consisting of four Jamesway huts, heavy schedule almost every day, and much was was established on McGregor Glacier by a U.S. Navy accomplished. construction crew and occupied by the scientists on David Elliot and James Collinson returned to November 8. Fieldwork began on November 10 and McMurdo and the United States in mid-December, continued without any major break until December 22 and Donald Coates took over from Elliot as scientific when the camp was moved to the Amundsen Glacier. leader. The move to the Amundsen Glacier camp, The McGregor campsite had been occupied by a constructed by the U.S. Navy, was accomplished on Texas Tech University geological expedition during December 22. This camp (0.5 km southeast of the the 1964-1965 season; the skiway used then by the 1963-1964 camp of Long and others) was colder LC-130 planes was still outlined by barrels, but to and windier than the McGregor Glacier camp and avoid any possibility of striking buried objects, the more typical of the Transantarctic Mountains. Work skiway was placed in a different position. Unfor- from this camp suffered more weather delays than at tunately, this new skiway proved to have a number McGregor Glacier, but by late January all major of small crevasses crossing it diagonally, and on No- objectives were accomplished, and the camp was vember 25 one was uncovered that might have caused closed on January 21. damage to a plane. So the old runway was intensively probed and dragged, but no crevasses were found, and Geological investigations it was used without incident until the camp was closed. The snow surface on McGregor Glacier is the The Queen Maud Mountains have been investi- gated by a number of geological field parties (La 120W 140W 160W 180 160E 140E Prade, 1970; Long, 1965; McLelland, 1967; Minshew, 1966; McGregor, 1965a,b; Wade et al., 1965), and therefore the scientific program this season concen- 85S Bennett trated on specific problems rather than a regional 11,61, Platform Dominion 01 survey. The stratigraphy is set out in the table; the formation names established earlier in the Queen Amunds:nj coalsock Alexandra Range, 200 km to the northwest (Barrett, O W Bluff in press), are used because the individual units es- ShocIleton G1. 7 Patric, ) J 160 Ramsey GI Beardmore tablished there are recognizable also in the Queen 83 S 83 S / Maud Mountains. / Ross Information was gathered for the completion of The Cloudmaker and Plunket Point quadrangles and l6 OW Ice for compilation of five more quadrangles covering the area between the Shackleton Glacier and the Scott LEW Glacier. S 6 elf ARCTICA\ f-8Is Edmund Stump studied the metasedimentary and 9OE metavolcanic basement rocks. He found that the Late Precambrian metasedimentary Goldie Formation and its probable equivalent, the La Gorce Formation, crop Em out only northwest of the Ramsey Glacier and in the
July—August 1971 115 Geologic section of the Queen Maud Mountains.
Thickness, Age Formation Group or Supergroup Description m
Late Recent lateral moraines Cenozoic Sirius Semilithified till with water-sorted lenses Jurassic Kirkpatrick Basalt Ferrar Group Tholeiitic basalts, a few sedimentary inter- 420+ beds with conchostracans Ferrar Dolerite Sills and dikes of tholeiitic dolerite through- out pre-Jurassic rocks Prebble Pyroclastic and laharic deposits 460+ Triassic Falla Sandstone, shale, Dicroidiurn 200+ Fremouw Beacon Arkosic sandstone, green-gray mudstone 700+ Supergroup Lystrosaurus zone fauna near base Buckley Arkosic and volcanic sandstone, dark-gray 450 shale, coal, Glossopteris Permian Fairchild Beacon Massive arkosic sandstone 200 Mackellar Supergroup Medium to dark-gray shale, with sand- 160 stone interbeds Pagoda Tillite, sandstone, mudstone, interbedded 3-150 Devonian Alexandra Beacon Sandstone, cross-bedded, fine to coarse 0-90+ Supergroup grained, buff Cambrian Henson Marble Marble, coarse-grained, gray to white, with Leverett minor intercalated clastic layers Wyatt Ross Massive, dark, silicic volcanics, minor units Taylor Supergroup of marble and cross-bedded quartzite Late Goldie Metagraywacke and shale, black, thin- to Precambrian La Gorce thick-bedded southern Amundsen and Scott Glacier areas, the uniform throughout the central Transantarctic Moun- intervening area being formed of the much less de- tains, and formations are relatively easy to correlate formed volcanics of the Wyatt and Taylor Formations over long distances despite this being a terrestrial and of the Queen Maud Batholith. On the Nilsen sequence. David Elliot investigated several Triassic Plateau the metavolcanic rocks are clearly uncon- sequences and one reported Triassic sequence in formable on the metasedimentary rocks. John the Dominion Range that turned out to be Permian. Burgener of the University of Wisconsin mapped and He also assisted Vaughn Wendland in a detailed sampled the Queen Maud Batholith for a geochemical study of the Jurassic lavas at Mount Bumstead and study. collected conchostracans from Mauger Nunatak, a Donald Coates made a regional study of the locality from which Paul Tasch had hoped to collect Permian tillite, which covers the post-Devonian the year before but was unable to reach because of erosion surface. The tillite ranges from silty with weather conditions. scattered pebbles to sandy with boulders. It is 3 to Paul Mayewski and R. P. Goldthwait studied 10 m thick over extensive areas of the fiat, post- glacial geology and discovered deposits of an early Devonian Maya erosion surface and as much as stage of glaciation in several areas.. These deposits 150 m thick in small areas. Coates also carried out are especially well preserved on Bennett Platform a regional reconnaissance gravity survey to extend and near Plunket Point in the Dominion Range. They the work of the previous season. correlate with the Sirius Formation, which was first Helmut Ehrenspeck investigated postglacial Per- investigated by Mercer (in press) at Mount Sirius mian sediments and collected Glossopteris from the near Coalsack Bluff. Investigation of the Sirius Buckley Formation. He also measured and sampled Formation will be extended to the McMurdo region Lower Triassic sedimentary rocks. James Collinson in the 1971-1972 season. Evidence was also found studied the Triassic stratigraphy and in particular indicating former higher levels of the Shackleton Glacier and other major outlet glaciers. the vertebrate fossil-bearing beds of the lower Fremouw Formation. Both the Fremouw and the Falla Exciting paleontological discoveries Formations, defined in the Queen Alexandra Range, were recognized in this area. The stratigraphy of the Undoubtedly, the most exciting discoveries were Triassic, like that of the Permian, is remarkably in vertebrate paleontology. On the first day of field-
116 ANTARCTIC JOURNAL awfiadgffiviam
work, as happened also last season at Coalsack Bluff, Force. We would like to thank the U.S. Navy for a major fossil locality was discovered. This season the support we have had during the last two field Collinson found fossil bones and a Thrinaxodon cast seasons. Much of the work accomplished would have on the lower slopes of Mount Kenyon, and sub- been extremely arduous and time-consuming, and sequently four more major sites were discovered by no small part of it would have been impossible with- vertebrate paleontologists James Kitching, Tom Rich, out the use of helicopters. Perhaps we can best ex- and John Ruben and by others. However, almost all press our thanks by listing some of the accomplish- prospecting and collecting was done by the vertebrate ments and discoveries of the 1969-1970 and 1970- aleontologists. At Coalsack Bluff, the fossils are 1971 field seasons: disarticulated fragments in channel sandstones and, 1. Discovery of Lystrosaurus at Coalsack Bluff 4lthough not badly waterworn, are far from ideal, (Colbert, in press). lecause identification of amphibians and reptiles 2. Discovery of five major vertebrate localities in rquires adequate skull material. The only species the Shackleton Glacier area (Kitching et al., Positively identified so far from the 1969-1970 finds in preparation). at Coalsack Bluff is Lystrosaurus murrayi (Colbert, 3. Discovery at Mount Augusta of the paleobotani- ii press), which is the most common species in the cally very important silicified peat related to Lystrosaurus Zone of lower Triassic age in the Karroo the Glossopteris flora (Schopf, 1970). s quence of South Africa. In the Shackleton Glacier 4. Discovery also of Triassic silicified peat related area, however, the vertebrate fossils occur not only to the Dicroidium flora. s disarticulated bones in sandstones but also as articu- 5. Discovery of Jurassic Holostean fish (Schaeffer, I ted skeletons. These occur in fine-grained sandstone in preparation). nd siltstone that was deposited in the floodplain 6. Discovery of new localities of conchostracan djacent to the streams depositing the coarse channel fossils (Tasch, 1970). sandstone. These fossiliferous rocks have yielded 7. Regional mapping, which has gathered enough abundant Lystrosaurus murrayi and several specimens information for 1:250,000 reconnaissance geo- of Thrinaxodon, an advanced mammal-like reptile. logic maps covering the area from the Queen Other elements of the fauna include thecodont rep- Alexandra Range to the Scott Glacier. tiles and labyrinthodont amphibians, but identification 8. Discovery of extensive areas of late Cenozoic must await further study by James Kitching and tillite that is probably related to the early stages Edwin Colbert, who are currently studying the of glaciation of Antarctica (Mercer, in press; collection from Coalsack Bluff. Nevertheless, certain Mayewski, in preparation). preliminary conclusions can be drawn from the new 9. Regional correlation and interpretation (much fauna: (1) the fauna collected this season appears of it still in the stage of data reduction) of the to be very similar to the fauna of the Lower Triassic basement rocks and the Beacon strata. Published Lystrosaurus Zone of the Karroo sequence and (2) results stemming from the 1969-1970 season this great similarity is substantial evidence for include Gunner and Faure (in press), Coates Gondwanaland and continental drift. Lystrosaurus (in press), Elliot et al. (1970, in press). was the first definitive evidence for land connection between Antarctica and the other southern continents, References but it is only one genus. Now the varied vertebrate fauna strengthens greatly the argument for sub- Barrett, P. J. In press. Stratigraphy of the mainly fluviatile stantial land connection. and Permian and Triassic Beacon Group rocks, Beardmore The fossils collected in the 1970-1971 season are Glacier area. In: Antarctic Geology and Geophysics. under study at present, and a preliminary report is Universitetsforlaget, Oslo. in preparation (Kitching in preparation). The Coates, Donald A. In press. Pagoda Formation: Evidence et al., of Permian glaciation in the central Transantarctic Moun- discovery of five major fossil sites in one season is tains. In: Antarctic Geology and Geophysics, Univer- remarkable and suggests that vertebrate fossils are sitetsforlaget, Oslo. widely distributed. However, Antarctica is not the Colbert, E. H. In press. Triassic tetrapods from Antarctica. ideal place for field work, and it may be many years In: Antarctic Geology and Geophysics. Universitetsfor- laget, Oslo. before the full extent of the fauna is determined and Elliot, D. H. 1970. Beardmore Glacier investigations, 1969- comparisons made with the faunas from the other 1970. Narrative and geological report. Antarctic Journal Gondwana continents. of the U.S., V(4) : 83-85. Elliot, David H., E. H. Colbert, W. J. Breed, J. A. Jensen, and J. S. Powell. 1970. Triassic tetrapods from Antarctica: Accomplishments since 1969 evidence for continental drift. Science, 169: 1197-1201. The scientists were ably assisted in the field by Elliot, David H., James W. Collinson, and Jon S. Powell. In press. Stratigraphy of Triassic tetrapod -bearing beds Philip Colbert, Stephen Etter, and Vaughn Wend- of Antarctica. In: Antarctic Geology and Geophysics. land, and various members of the U.S. Navy Support Universitetsforlaget, Oslo.
July—August 1971 117 Gunner, J., and Gunter Faure. In press. Rb-Sr geochronology As a continuation of the 1969-1970 exploration, of the Nimrod Group, central Transantarctic Mountains. three paleontologists—Mr. Thomas H. Rich of the In: Antarctic Geology and Geophysics. Universitetsfor- laget, Oslo. American Museum of Natural History, Mr. John A. Kitching, J . W., J. W. Collinson, D. H. Elliot, and E. H. Ruben of the University of California (Berkeley), Colbert. In preparation. Lystrosaurus zone (Triassic) and the writer—carried on investigations during fauna from Antarctica. 1970-1971 in two localities: the McGregor Glacier La Prade, K. E. 1970. Permian-Triassic Beacon Group of the Shackleton Glacier area, Queen Maud Range, Trans- area (November 10 to December 22) and Amundsen antarctic Mountains, Antarctica. Geological Society of Glacier (December 22 to January 7). Working with America. Bulletin, 81: 1403-1410. others under the scientific leadership of Dr. David Long, W. E., 1965. Stratigraphy of the Thorvald Nilsen Elliott of The Ohio State University, the three men Mountains, Queen Maud Range, central Antarctica. had as their main objective the exploration of the Special Paper. Geological Society of America, Abstracts for 1964, 82: 124. Frernouw Formation, a sequence of horizontal sanà- Mayewski, P. In preparation. Ph.D. Dissertation, The Ohio stones and mudstones deposited during the eary State University. Triassic. The extensive Fremouw deposits, intruded McGregor, V. R. 1965a. Notes on the geology of the area and capped by Ferrar dolerite dykes and sills, bear between the heads of the Beardmore and Shackleton Glaciers, Antarctica. New Zealand Journal of Geology a remarkable similarity to the lower Triassic sedi - and Geophysics, 8(2) : 278-291. ments characteristic of the Karroo Basin of South McGregor, V. R. 1965b. Geology of the area between the Africa. Axel Heiberg and Shackleton Glaciers, Queen Maud On the first day in the field, Dr. James Co11insoi Range, Antarctica. Part 1—basement complex, structure, of The Ohio State University discovered an almost and glacial geology. New Zealand Journal of Geology and Geophysics, 8(2) : 314-343. complete skeletal impression of the mammal-like McLelland, D. 1967. Geology of the basement complex, reptile Thrinaxodon in a thick sandstone horizon Nilsen Plateau. Unpublished manuscript. the base of Mount Kenyon on the western slope of Mercer, J . H. In press. Some observations on the glacial a hill now called Thrinaxodon Cul (85°12 . geology of the Beardmore Glacier area. In: Antarctic Geology and Geophysics. Universitetsforlaget, Oslo. 174°19 W.). Later, other specimens of the same Minshew, V. H. 1966. Stratigraphy of the Wisconsin Range, genus were discovered 450 m east of the first di- Horlick Mountains, Antarctica. Science, 152: 637-638. covery. Lystrosaurus and some small lizard-like rep- Schaeffer, B. In preparation. Jurassic fishes from Antarctica. tiles were also recovered from this locality, and a rich Schopf, J . M. 1970. Petrified peat from a Permian coal fossil bone bearing channel in a sandstone horizon bed in Antarctica. Science, 169: 274-277. Tasch, P. 1970. Paleolimnology of some antarctic non- was located at the base of Thrinaxodon Cul. marine deposits. Antarctic Journal of the U.S., V(4): From Mount Kenyon the activities of the pale- 85-86. ontologists were extended to Kitching Ridge (85 12 S. Wade, F. A., V. L. Yeats, J . R. Everett, D. W. Greenlee, 177 06 W.), Mount Rosenwald, Collinson Ridge K. E. La Prade, and J. C. Schenk, 1965 . The geology of the central Queen Maud Range, Transantarctic Moun- (85 0 131S. 175 0 21 W.), part of Halfmoon Bluff, tains, Antarctica. Texas Tech University Research Report Shenk Peak, and as far afield as Graphite Peak, where Series, Antarctic Series, 65-1, 54 p. the first indication of vertebrate fossils in the Ant- artic was discovered by Peter Barrett during the austral summer 1967-1968. Vertebrate fossils from the Antarctic are character- ized by the genus Lystrosaurus, a highly specialized, mammal-like reptile especially abundant in the lower Triassic beds of South Africa. Discovery of this Paleontological investigations genus a year ago afforded a definite clue to the close relationship between the ancient land-dwelling reptiles in the McGregor Glacier area of South Africa and Antarctica. In addition to Lystrosaurus, the fossil remains of small thecodonts, JAMES W. KITCHING labyrinthodont amphibians, the skulls and skeletons of Thrinaxodon, and a small reptile known as Bernard Price Institute Procolophon were recovered, as well as a large number for Palaeontological Research of small lizard-like reptiles most probably belonging University of the Witwatersrand, Johannesburg to the suborder Captorhinomorpha and the order Eosuchia. Thrinaxodon, like Lystrosaurus and Procolophon, Readers may recall the discovery of a large number is characteristic of the reptile fauna represented in of tetrapod fossil remains—including the genus the Lower Triassic deposits of South Africa. The Lystrosaurus—at Coalsack Bluff during the 1969- collections from the last two seasons suggest beyond 1970 austral summer and the impact this discovery reasonable doubt that Antarctica and Africa were had on geological thought. connected during Triassic times, forming the ancient
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