Paleoenvironmental reconstruction of the Middle Eocene Trieste-Pazin basin (Croatia) from benthic foraminiferal assemblages

摘要: Foraminiferal assemblages from four stratigraphic sections of the Trieste-Pazin basin in central Istria, Croatia (southwest- ern Tethyan realm) were investigated to reconstruct paleoenvironmental conditions and determine age these deposits. The fol- lowing five Middle Eocene planktonic foraminiferal zones identified range frequency species: Globigerinatheka kugleri/Morozovella aragonensis Zone (E9), Acarinina topilensis (E10), Morozovelloides lehneri (E11), Orbulinoides beckmanni (E12), crassatus (E13). A data set benthic foraminifera relative has been subjected R- Q-mode cluster analyses demonstrate linkage between taxa distribution gra- dients. Benthic biofacies indicate that environment evolved an initially mesotrophic upper bathyal slope setting towards a deeper, more oligotrophic, middle influenced by turbidity currents. oligotrophy was result deepen- ing processes, consequential decrease organic flux. documented short-term periods eutrophic within deeper oligotrophic regime might represent paleoceanographic influence water-masses adjacent northwest, thus recording its paleogeographic connection with during (Lutetian).