History of the Belanovica (Serbia) Neogene lake basin inferred from petrological and geochemical data

Abstract

The petrological and geochemical composition of Neogene lacustrine successions and basement rocks of the Belanovica basin in Central Serbia, were investigated in three exploration boreholes, drilled in the central part of the former lake. Two boreholes accessed the basement, while the third one terminated in the lowermost Neogene interval, composed of coarse-grained clastics. Formation and diversification of the lake basin was influenced by strong syndepositional volcanic activity. The vertical distribution of selected elements from basal clastics (Cr, Ni, and Mg) and from overlying lake sediments (Ba, Sr, Na, K, etc.) indicates both the southern and northern margins of the basin, as potential source areas. The elemental concentrations are consistent with petrography. Based on the derived data, a reconstruction of the basin history is presented. The lack of index fossils resulted in a less accurate stratigraphy and the need for further updating by employment of the fission-track low-temperature thermochronometers. Additionally, outcrop studies and correlation with lake sediments in the Valjevo-Mionica basin is suggested.