Vegetation and climate dynamics during the early Middle Miocene from Lake Sinj (Dinaride Lake System, SE Croatia)

Abstract

Pollen data from sediments from an outcrop section in the ancient Lake Sinj (Dinaride Lake System, SE Croatia) record variations in vegetation during the early Middle Miocene. Good correspondence between the palaeo-vegetation and the sedimentological profile suggests that both records are mainly controlled by variations in the past climatic conditions. Periods of frequent coal deposition generally coincide with high abundance of thermophilous and xeric indicators suggesting warm and dry climate. Pollen and sediment records show two large-scale warming and shallowing-upward cycles and smaller-scale cyclicity. The high relative percentage of warm pollen taxa in the entire record, with Engelhardia as the main component, generally indicates a subtropical humid climate for this area during the early Middle Miocene, probably related to the Miocene Climatic Optimum. This study shows a response of the vegetation to climate change at short-term, probably related to orbital cyclic variations in summer insolation during the Middle Miocene.