1. BIOTIC CRISES RELATED TO THE PALEOCLIMATE DETERIORATION.
- Author
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Melinte-Dobrinescu, Mihaela, Ion, Gabriel, Briceag, Andrei, Anton, Eliza, and Apotrosoaei, Vlad
- Subjects
OCEAN acidification ,PALEOCLIMATOLOGY ,CLIMATE change ,ICE caps ,SEAWATER ,METEORITES ,OLIGOCENE Epoch - Abstract
Our planet experienced many intervals of climate deterioration due to terrestrial causes, such as intensified volcanism and a very active tectonic regime or extraterrestrial causes. The later includes major meteorite impacts and change in the exosphere, mostly linked to the modification of sunlight amount leading to glaciations. The most sensitive organisms to climate changes are the marine planktonic ones, especially the coccoliths and dinoflagellates. This paper describes modification in the marine planktonic world during three specific intervals: (1) K/T boundary, when the meteorite impact led to the acidification of ocean surface waters and the disappearance of over 80 % of marine planktonic taxa; (2) Oligocene cooling and instauration of permanent North Pole ice cap, along with the separation of the Tethys Ocean in the Mediterranean and Paratethyan Sea; the later occupied large areas in the Central and Eastern Europe; (3) The reconnection of the Black Sea with Mediterranean during Holocene times. These events are accompanied by shift of calcareous nannoplankton assemblages, including blooms of Braarudosphaera bigelowii, along with calcareous dinoflagellate taxa of Thoracosphaera. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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