International Journal of Earth Sciences

, Volume 95, Issue 1, pp 119–142 | Cite as

Paleoceanography and climate of the Badenian (Middle Miocene, 16.4–13.0 Ma) in the Central Paratethys based on foraminifera and stable isotope (δ18O and δ13C) evidence

  • Katalin Báldi
Original Paper


Benthic foraminifera and stable isotopes analyses revealed changes emerging in the paleoceanographic scenery in the Paratethys. The percentage of inbenthic, oxyphylic taxa and diversity in the benthic foraminiferal assemblage showed increasing food supply (organic matter), decreasing oxygen level and growing stress on the sea floor. Oxygen isotopes measured in planktonic and benthic foraminifera pointed to strengthening stratification during the Badenian period. The carbon isotopes indicated intensified accumulation of light marine organic matter. This increasing stratification trend is especially pronounced by Late Badenian (13.5–13 Ma) when surface water oxygen isotope values are rather negative. A simple two-layer circulation model was worked out for the Badenian Paratethys explaining these characteristic environmental changes. An antiestuarine (lagoonal) circulation is assumed for the Central Paratethys during the Early (16.4–15 Ma) and mid Badenian (15–13.5 Ma). The mid Badenian period of time comprises the short episode of evaporite formation in the Carpathian Foredeep and the Transylvanian Basin. Evidence presented here supported a reversal of circulation to estuarine type after the deposition of salts by Late Badenian (13.5–13 Ma). The Early Badenian antiestuarine circulation is suggested to associate with the high temperatures of the Mid-Miocene Climatic Optimum, and the Late Badenian estuarine circulation with the cooler period following it.


Miocene Paratethys Stable isotopes Foraminifera Climate 



The present study was funded by the postdoctoral grant of the National Science Foundation (OTKA D 042191). I am grateful for the isotope analyses carried out in the laboratory of Utrecht University and for their selfless support over the years. I am especially indebted to Dr. T. Kouwenhoven (Utrecht University) for her altruistic work of commenting and correcting the manuscript, greatly contributing to its present form. I am obliged to express my gratitude to Dr. I. Vetö (Hungarian Geological Institute) for comments concerning the isotope analyses and Dr. P. Müller (Hungarian Geological Institute) for comments on the Badenian stratigraphy and paleogeography. I am grateful to Prof. Dr. G.J. Van der Zwaan, and Dr. J.E. Meulenkamp (Utrecht University) for the fruitful discussions and support. Thanks are due to my close colleague Dr. O. Sztanó (Eötvös University Budapest) for her remarks concerning the present work and my project leader Dr. A. Nagymarosy (Eötvös University Budapest) for sharing his thoughts on stratigraphy. I am grateful for the useful comments and suggestions of Dr. F. Rögl, Dr. E.Turco and an anonymous reviewer.


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Authors and Affiliations

  1. 1.Department of Physical and Historical GeologyEötvös University BudapestBudapestHungary
  2. 2.Department of Paleontology, Micropaleontology Research GroupUniversity of ViennaViennaAustria

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