Keywords and Phrases
Geobiology; Biostratigraphy; Central American Seaway; Colombia; Marine palynology; Paleoceanography
"Marine palynomorphs, mainly dinoflagellate cysts and acritarchs, constitute excellent proxies for biostratigraphic and paleoceanographic studies in neritic sequences. Neogene marine palynological studies have mostly focused on the Northern Hemisphere, resulting in the scarcity of dinoflagellate cysts and acritarchs from tropical latitudes. Forty samples encompassing the late Chattian-late Burgidalian time interval (~24.1- 17.3 Ma) in the Southern Caribbean were analyzed for their marine palynological contents. A biostratigraphic scheme for the region is proposed and includes the upper Chattian-lower Aquitanian Minisphaeridium latirictum Interval Zone (~23.9-22.0 Ma), the upper Aquitanian Achomosphaera alcicornu Interval Zone (~22.0-20.3 Ma), and the Burdigalian Cribroperidinium tenuitabulatum Interval Zone (~20.3-17.5 Ma). Two peridinioid dinoflagellate cyst species, Cristadinium lucyae sp. nov., and Trinovantedinium uitpensis sp. nov., and the acritarch Quadrina? triangulata sp. nov. are formally described. A conspicuous shift from a peridinioid-dominated dinoflagellate cyst assemblage to a gonyaulacoid-dominated assemblage occurs near the Aquitanian- Burdigalian boundary (~20.7 Ma), indicating a reduction in marine primary productivity. This paleoproductivity shift is linked to the initial constriction of the Central American Seaway -- the oceanic pathway along the tectonic boundary between the South American plate and the Panama microplate"--Abstract, page iv.
Hogan, John Patrick
Geosciences and Geological and Petroleum Engineering
Ph. D. in Geology and Geophysics
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
- Early Miocene marine palynology of the Colombian Caribbean Margin: Biostratigraphic and paleoceanographic implications
- New acritarch and peridinioid dinoflagellate cysts species from the Oligocene-Miocene of Colombia
ix, 66 pages
© 2021 Damian Cardenas Loboguerrero, All rights reserved.
Dissertation - Open Access
Cardenas, Damian, "Neogene dinoflagellate cysts from the tropical americas" (2021). Doctoral Dissertations. 2967.