Author	Cocozza, C.D. and Clarke, C.M.
Year	1992
Journal	In: Duane, A.M., Pirrie, D. and Riding, J.B. (eds.), 1992: Palynology of the James Ross Island Are
Title	Eocene microplankton from La Meseta Formation, northern Seymour Island

Abstract Cocozza, C.D. and Clarke, C.M., 1992; Eocene microplankton from La Meseta Formation, northern Seymour Island. In: Duane, A.M., Pirrie, D. and Riding, J.B. (eds.), 1992: Palynology of the James Ross Island Area, Antarctic Peninsula. Antarctic Science, Volume 4,No.3: 355-362 Special Issue, September 1992. Blackwell Scientific Publications Abstract: Twenty two samples collected from the Tertiary La Meseta Formation of Cape Wiman, Seymour Island, Antarctic Peninsula yielded abundant and moderately diverse assemblages of marine palynoflora, dominated by dinoflagellate cysts, together with acritarchs and chlorophyta. The assemblages can be divided into three associations: Association 1, characterized by low diversity dinoflagellate assemblage of late Early Eocene age which are dominated by E~ligmadi~lium cyli~ldrifloriferum; Association 2 characterized by more diverse dinoflagellate cyst assemblages, which show a marked decrease in the dominance of E. cyli~Zdrifioriferum, and an increase in relative abundance of Areospllaeridium cf. diktyoplokus; and Association 3 which is characterized by a decrease in dinoflagellate cyst diversity up section. Changes in dinoflagellate cyst dominance and diversity throughout the section suggests a gradation from a stressed, shallow marine palaeoenvironment to a more open near-shore, shallow marine system becoming progressively more nearshore up section. The assemblages are no older than late Early Eocene in age, and possibly as young as Mid-Late Eocene.