include bivalves, gastropods, echinoderm spines, and abun-dant wood.

This work was supported by National Science Foundationgrant DPP 80-20096.

References

Andersson, J. C. 1906. on the geology of Graham Land. Bulletin of theGeological Institute of the University of Upsala, 7, 19-71.

Elliot, D. H., Rinaldi, C. A., Zinsmeister, W. J., Trautman, T. A., Bryant,W. B., and del Valle, R. 1975. Geological investigations on SeymourIsland, Antarctic Peninsula. Antarctic Journal of the U.S., 10(4),182-186.

Howarth, M. K. 1966. Ammonites from the Upper Cretaceous of theJames Ross Island Group. Bulletin of the British Antarctic Survey, 10,55-69.

Olivero, E. G. 1981. Esquema de zonaciOn de ammonites del CretácicoSuperior del Grupo de Islas James Ross, Antártida. VIII CongressoGeologico Argentino, San Luis, September 20-27, 1981. Acta, 311,897-907.

Rinaldi, C. A. 1982. The Upper Cretaceous in the James Ross IslandGroup. In C. Craddock(Ed.), Antarctic geoscience. Madison: Universityof Wisconsin Press.

Rinaldi, C. A., Massabie, A., Morelli, J., Rosenman, H. L., and delValle, R. 1978. GeologIa de la Isla Vicecomodoro Marambio. Contribu-ciones del instituto Antdrtico Argentino, 217, 1-37.

Spath, L. F. 1953. The Upper Cretaceous cephalopod fauna of GrahamLand. Falkland Islands Dependencies Survey, Scientific Reports, 3, 1-60.

Palynological investigations ofCampanian to lower Oligocenesediments on Seymour Island,

Antarctic Peninsula

-;ROSEMARY A. ASKIN

Geology DepartmentColorado School of MinesGolden, Colorado 80401

R. F1\11lY F1I:MIN;

Department of Geological SciencesUniversity of Colorado

Boulder, Colorado 80309

Palynomorphs have been recovered from all of the first prepa -rations of samples collected during the February-March 1982expedition to Seymour Island. In all, 363 samples were col-lected, mainly from Seymour Island but also from Snow HillIsland (provided by B. Huber), Cape Lamb on Vega Island, TheNaze on northeastern James Ross Island, and Cape Melville onKing George Island.

The stratigraphy of Seymour Island is summarized by Mac-ellari and Huber (Antarctic Journal, this issue; Campanian to? Paleocene, Lopez de Bertodano and Sobral Formations) andby Zinsmeister and DeVries (Antarctic Journal, this issue; ? Pal-eocene to lower Oligocene, Seymour Island Group). Apart fromcemented resistant sandstone beds and concretions, most ofthe sedimentary sequence on Seymour Island is unconsoli-dated. Fine-grained sediments (mud and silt) are abundant inplaces particularly in the Sobral Formation. Much of the fine-grained sediment is carbonaceous and highly suitable for pal-ynological sampling.

The best continuously exposed section of predominantlyfine-grained sediment crops out in the central part of SeymourIsland. This approximately 300-meter-thick section includes theSobral Formation and is believed to include the Cretaceous-

A B

/

C

4.1E F

5Opm

Photomicrographs of fossil pollen from Seymour Island (bar isequivalent to 50 micrometers). A, M!crocachryidites antarcticusCookson; B, Phyllocladidites mawsoniiCookson; C, Nothofagiditesfleming!! (Couper) Potonie; D, Proteacidites parvus Cookson; E,Haloragacid!tes harris!! (Couper) Harris; F, Tricolpates sp. A, B, D,and E occur in the Sobral Formation and throughout the SeymourIsland Group; C occurs in the Seymour Island Group; and F occursIn the Sobral Formation and the Cross Valley Formation.

70 ANTARCTIC JOURNAL

Tertiary boundary. Over much of this section it was possible tocollect at 1.5-meter intervals; for most of the remainder, wecould collect at 3-meter intervals.

Cretaceous strata (Lopez de Bertodano Formation) croppingout on the southwestern part of the island are characterized bylow topographic relief (in comparison with the rest of the is-land), and much of the strata is covered with debris; therefore,continuous sampling for palynomorphs was not possible in theolder sandy units.

Sampling was carried out throughout the Cross Valley Forma-tion, although horizons suitable for palynomorphs are rare inthe predominantly coarse-grained lower part of the formation.A coal bed presumed to be included in the Cross Valley Forma-tion (see Fleming and Askin, Antarctic Journal, this issue) wassampled, as was much of the La Meseta Formation, including aunit adjacent to the marsupial bone locality (see Woodburne,Antarctic Journal, this issue).

Distinct palynomorph assemblages are recognized from sam-ples provided by the 1974-75 expedition of Elliot and others(1975) and our recent collections (figure). Podocarpaceous pol-len predominates in Sobral Formation sediments, with lesscommon Nothofagidites spp. (fusca and brassi groups), some pro-teaceous species, and pteridophyte spores. In the SeymourIsland Group, podocarpaceous species and Nothofagidztes spp.(fusca, brassi, and menziesii groups) are dominant; proteaceouspollen is often abundant but shows a noticeable decline inrelative abundance in the upper part of the La Meseta Forma-tion. A succession of other distinctive and previously un-described angiosperm pollen, some of which appear to haverestricted ranges, occurs throughout. A few of these speciesalso occur in the Ross Sea region (Truswell personal communi-

cation), but some may have been endemic to the Seymour Islandregion. Simple tricolpate species are common in Sobral Forma-tion samples.

In summary, a good, representative sampling for pal-ynomorphs on Seymour Island has been obtained. These sam-ples may provide both a palynostratigraphic zonation and infor-mation on the changing vegetation and paleoenvironmentalconditions in the area.

We thank fellow members of the expedition for companion-ship and enthusiastic support, and Captain Coste and the crewof USCGC Glacier for logistic support. This research is funded byNational Science Foundation grant DPP 80-20095.

References

Elliot, D. H., Rinaldi, C., Zinsmeister, W. J., Trautman, T. A., Bryant, W.A., and del Valle, R. 1975. Geological investigations on SeymourIsland, Antarctic Peninsula. Antarctic Journal of the U.S., 10(4),182-186.

Fleming, R. F., and Askin, R. A. 1982. Early Tertiary coal bed onSeymour Island, Antarctic Peninsula. Antarctic Journal of the U.S.,17(5).

Macellari, C., and Huber, B. T. 1982. Cretaceous stratigraphy ofSeymour Island, East Antarctic Peninsula. Antarctic Journal of the U.S.,17(5).

Truswell, E. M. Personal communication, 1981.Woodburne, M. 0. 1982. Newly discovered land mammal from Ant-

arctica. Antarctic Journal of the U.S., 17(5).Zinsmeister, W. J., and DeVries, T. J . 1982. Observations on the stratigra-

phy of the lower Tertiary Seymour Island Group, Seymour Island,Antarctic Peninsula. Antarctic Journal of the U.S., 17(5).

Observations on the stratigraphy ofthe lower Tertiary Seymour

Island Group, Seymour Island,Antarctic Peninsula

WILLIAM J. ZINSMEISTER and THOMAS J. DEVRIES

Institute of Polar StudiesOhio State UniversityColumbus, Ohio 43210

The 1981-82 geological program on the Tertiary of theSeymour Island Group represents a continuation of fieldworkinitiated on Seymour Island by a joint U.S.-Argentina expedi-tion during the austral summer of 1974-75 (Elliot et al. 1975).Results of the fieldwork this year have greatly enhanced ourknowledge of the Tertiary succession on Seymour Island andthe stratigraphic relationships between the Tertiary and theunderlying Upper Cretaceous Marambio Group. The most sig-nificant events were recognition of approximately 300 meters of

additional sediments in the lower part of the La Meseta Forma-tion in Cross Valley and verification of the formation's unconfor-mable relationship with the underlying Cretaceous.

During the 1974-75 field season, Elliot and Trautman (1982)determined that the La Meseta Formation has a thickness ofabout 450 meters. Because of the faulted nature of the basalcontacts of the sections they measured at the northern end ofthe island, it was suggested that the formation was probablythicker. Work this year around Cross Valley (figure 1) revealedapproximately 300 meters of additional sandy siltstones refera-ble to unit I of the La Meseta.

These sediments are characterized by finely laminated tothinly bedded sandy siltstones with clayey sands. Several fos-siliferous, coarser, sandy facies similar to the shell banks of unitII were encountered approximately 200 meters above the base.Lenticular beds near the western mouth of Cross Valley con-tained moderately abundant leaf impressions and fish scales, aswell as marine mollusks. Fossilized logs, which are common inthe overlying shell bank facies of unit II, were not observed inthis newly discovered part of the La Meseta Formation.

We were also able to demonstrate that the sequence acrossCross Valley was nearly continuous, not cut by a series of largefaults as previously thought (Elliot et al. 1975). Several smallfaults were observed, but none had any significantdisplacement.

711982 REVIEW