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 Unpublished manuscript.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°19W.). 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 12S. Wade, F. A., V. L. Yeats, J . R. Everett, D. W. Greenlee, 17706W.), 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 21W.), 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

118 ANTARCTIC JOURNAL supercontinent Gondwanaland. All the fossil reptilian understanding of the relationships among the terrace remains from Antarctica are those of terrestrial ani- sediments, the fluctuations of glaciation, and the mals that could have moved back and forth only by periglacial phenomena will also result from the studies. way of an extensive dry-land connection. This evi- We thank the National Science Foundation for its dence of a land-living fauna inhabiting a broad invitation to participate in USARP field activities, continental region is another factor of utmost impor- and the pilots and crews of VXE-6 for assistance tnce supporting the theory of continental drift. in the field.

Belgian exchange scientists Geologic studies of basement rocks in the dry valleys in southern Victoria Land

T. VAN AUTENBOER ROBERT F. FLORY, DONALD J . MURPHY, SCOTT B. SMITHSON, and ROBERT S. HOUSTON Belgian Antarctic Expeditions Department of Geology University of Wyoming The dry valleys west of McMurdo Sound have been studied by a host of scientists representing a very wide scope of interests. As a result, much general During the 1970-1971 field season, a field party information exists about the valleys, and several mapped basement rocks on Skelton Glacier. It had reconnaissance maps of the glacial deposits have been hoped that the heavy snowfall that had ham- been prepared. However, detailed and systematic pered field work in 1969-1970 would not be as se- studies are still lacking in some fields. This fact was vere. Unfortunately, the area between Baronick and kept in mind when our 1970-1971 geology program Cocks Glaciers was again marked by heavy snow and was established in collaboration with Dr. P. Calkin high winds. Despite the weather problems, it was of the University of Buffalo in New York. possible to map the general geology with the aid of Dr. R. Paepe (Belgian Geological Survey), whose low-level aerial photographs taken in early Decem- main interest is in the fossil permafrost features of ber by the U.S. Navys Antarctic Development Squad- the European Pleistocene, and Mr. E. Paulissen ron Six. (National Center for Geomorphology), interested in geomorphologic mapping, carried out the program. The Ant Hill Limestone between Hobnail Peak Paying attention to stratigraphy, sedimentology, and and Cocks Glacier is complexly folded, but it has been periglacial phenomena of the terraces, the geologists possible to subdivide the formation by use of top and spent the first half of the season in the Taylor Valley bottom criteria into five lithologic units. From oldest around Lake Fryxell and the second half in the same these are thin layered metalimestone, graywacke-mud- valley near the Ross Sea. Several well exposed (up stone, quartzite, slate, and metalimestone. The pre- to 100 m long and 10 to 15 in sections through vailing strike of bedding in these units is east, chang- the terraces were mapped and the lithostratigraphy ing to north-northeast near Hobnail Peak. The major recorded in great detail. Numerous samples were structural feature north of Cocks Glacier is an east- taken for mineralogical, morphometric, and grain- plunging syncline with its southern limb cut out by a size analyses. major northeast-striking fault. The east-trending Small-scale geomorphologic mapping over the lower structural pattern is disrupted by later north-striking Taylor Valley was carried out. Special attention was fold systems. paid to the distribution and relationship between Despite a careful search of bedding planes, no fos- deposits caused by local glaciation, drainage glaciers, sils were found in the Ant Hill Limestone. Some orbi- and Ross Ice Shelf invasions. Additionally, longitudi- cular structures, which may be organic features, were nal profiles along valleys cutting the terraces were found in the limestone near Cocks Glacier. measured around Lake Fryxell and near the Ross Work has continued on samples collected during the Sea. Indications are that several terrace levels are at 1969-1970 field season in the Meserve Glacier area. similar heights on both sides of lower Taylor Valley. The rocks exposed between the Meserve and Good- This work will establish the relationship between the speed Glaciers are now known to include mineral as- two topographic bases (or levels) conditioning the semblages containing potassium feldspar, biotite, silli- erosion process in each area. We hope that a better manite, cordierite, plagioclase, quartz, and garnet, and

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