The Slovenian Basin extends in an east-west direction of central Slovenia. Westwards it continues nearly to the Italian border, and eastwards it passes into neighbouring Croatia and Hungary. The present exposed parts of the Basin measure about 170 km by 40 km. The Slovenian Basin became established during the Ladinian and it persisted continuously until the Late Cretaceous. Several geological studies of these sediments have been conducted, among which conodont researches play an important part. The conodont data obtained enable a precise biostratigraphic definition of Triassic strata.