Eocene microplankton from La Meseta Formation, northern Seymour Island

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...

Full description

Bibliographic Details
Published in:Antarctic Science
Main Authors: Cocozza, Christopher D., Clarke, Ciara M.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1992
Subjects:
Online Access:http://dx.doi.org/10.1017/s0954102092000506
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102092000506
Description
Summary: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 association: Association 1, characterized by low diversity dinoflagellate assemblage of late Early Eocene age which are dominated by Enigmadinium cylindrifloriferum Association 2 characterized by more diverse dinoflagellate cyst assemblages, which show a marked decrease in the dominance of E. cylindrifloriferum , and an increase in relative abundance of Areosphaeridium 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.