In the small and extremely beautiful gorge of the Boljetinska Reka continuous geological column is exposed from transgressive Dogger to Aptian. The base is of red Permian sandstones and ignimbrites and the Jurassic part of the column could be divided into formations: Bivolja Stena Formation -the lowest unit (6 m) composed of sandstones and conglomeratic sandstones (Bajocian). Lepenski Vir Formation – (15 m) with lower part of Bajocian coarse-crystalline limestone and middle and upper parts of knotty micrite and biomicrite with filaments and Callovian ammonites (Macrocephalites macrocephalus). Pesača – Greben Formation, first 10 m are platy and layered micrite, biomicrite with filaments and radiolarians, and the upper part is with cherts (Oxfordian). Valanginian (38 m) includes gray marly micrite and marls with cherts Hauterivian (60 m) is of gray-greenish marly micrite and marls with ammonites. Barremian and Aptian (120 m) is represented by alternation of marls and marly limestones with Barremian ammonites (downward) and by gray- greenish marls and clayey sandstones with ammonites and rare belemnites (upward).