Permian and Triassic Palynostratigraphy of the Central Transantarctic Mountains

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This award supports a project to establish a palynostratigraphic framework for the Permian to Triassic sedimentary rocks of the central Transantarctic Mountains. This will help provide a chronostratigraphic reference for Antarctic studies. Palynomorph data can also add to knowledge of the composition of the Permian and Triassic floras and has important biogeographic and paleoclimatic implications. This research will give a clearer picture of the timing and nature of southern high latitude biotic and climatic changes which are vital for understanding causes and effects of the end- Permian global biotic crisis and mass extinctions. This work will concentrate on the Shackleton Glacier area and includes one field season to collect samples and two years of laboratory work. Existing rock collections as well as samples collected by other geologists working in the Shackleton Glacier region will also be utilized to obtain as complete a stratigraphic section as possible. Correlations will be made with other parts of Gondwana and palynological data will be integrated with other fossil and lithologic data to establish a sound, process related stratigraphic framework. Field work will focus on the post-glacial sedimentary units of the Victoria Group (Beacon Supergroup): the Mackellar, Fairchild, Fremouw, and Falla Formations, and their equivalents. Except for marginally brackish, inland-sea Mackellar beds, the succession consists of fluvial and lacustrine deposits. Palynomorphs in these rocks are almost entirely spores and pollen from land plants, with occasional acritarchs. The zonation will build upon and formalize the preliminary zonation established previously for southern Victoria Land. Fossil spore and pollen assemblages can indicate their parent plants and thus reflect at least part of the indigenous vegetation. This information can be added to other plant fossil (leaves, wood, et cetera) and paleosol data for paleoclimatic interpretations. Certain p alynomorph taxa (and assemblages) have specific biogeographical or environmental implications. Furthermore, stratigraphic and geographic distribution patterns of the palynomorphs yield information on evolutionary trends and rates, provincialism of the floras, and dispersal pathways.