Sedimentary record of the Dukla Basin (Outer Carpathians) and its implications for basin evolution

Abstract

The Late Cretaceous to Oligocene strata of the Dukla Nappe, which is a part of the accretionary wedge formed in front of the Carpathian orogen, record a history of the basin development from remnant to foreland basin stages. The lower part of the succession indicates the first stage of basin evolution characterized by turbidite systems fed from the E (NE) to W (SW). The system encompasses deposits of the Łupków and Cisna formations deposited in a channel-lobe transition (Łupków Fm.) and in sandstone-rich channelized lobes (Cisna Fm.) The transitional phase is represented by deposits of the Submenilite Formation derived from two different sources (SE and N) and deposited in a submarine slope/ramp environment. The third stage of basin evolution is marked by the advancing front of the Carpathian orogen resulting in peripheral foreland basin development. Increased tectonic activity led to a switch in sediment source from the SE to the NW, more complex topography of the basin and a change in sediment distribution. The initial phase of this stage is characterized by low-density turbidites and suspension fall-out sediments of the Menilite Fm. Discrete tectonic pulses are recorded by the thick Cergowa sandstones, mostly deposited by hybrid flows and high-density turbidity currents. A decrease in tectonic activity is suggested by heterolithic deposits  of the Krosno Fm. capping the sedimentary succession.