In the area where the Darnó Fault belt breaks up as a horsetail fault system in southern Slovakia and northwestern Hungary, beside the dominant lithologies such as calcareous siltstone and claystone several peculiar lithofacies generated in different paleoenvironments of the Buda (Hungarian) Paleogene and Fiľakovo/Pétervásara Eggenburgian Basins occur. Laminated limestone and shale classified as oil shale from the village of Drienovec, the Szendrö and the Bátka vicinities (Eocene-Oligocene and Early Miocene in age) came to existence in coastal lagoons and/or subtidal lagoons under anaerobic conditions at the bottom and affected by seasonal weather changes. The Bátka, Novaj, Budikovany, Bretka bioclastic and organogenic limestone units (Kiscellian and Egerian in age respectively) were deposited under shallow marine littoral conditions. The Drienovec and Szuhogy Conglomerate units originated under fluviatile conditions. Almost all mentioned lithologies were generated in genetic (conglomerate) or spatial (oil shale) relationship to the Darnó Fault Belt. The Bátka Limestone as well as the Hostišovce Member are related to the Šafárikovo Rise, a faulted structure perpendicular to the course of the Darnó Fault Belt.