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The entrenched Odra palaeovalley, cut into the bedrock of the distal margin (forebulge basal unconformity) of the Moravian Carpathian Foredeep (peripheral foreland basin) is filled with an almost 300 m thick pile of Miocene deposits. The directon of the valley (NW–SE to NNW–SSE) has been controlled by faults subparallel with the system of “sudetic faults“. The sedimentary succession consists of 5 facies associations/depositional environments, which are interpreted (from bottom to top, i.e. from the oldest to the youngest) as: 1 – colluvial deposits to deposits of alluvial fan, 2 – deposits of alluvial fan, 3 – fan-delta deposits, 4 – shallow water delta to nearshore deposits and 5 – open marine deposits. This fining-up and deepening-up succession reveals the following: the formation of the new flexural shape of the basin; deep erosion connected with uplift and tilting of the forebulge and reactivation of the NW–SE trending basement faults; the Early/Middle Miocene sea level fall; alluvial deposition mostly driven by tectonics and morphology; forebulge flexural retreat; Middle-Miocene sea level rise; back-stepping of valley infill; marine invasion during the Early Badenian with shift of the coastline further landward of the pallaeovalley. Tectonics related to contemporary thrusting processes in the Western Carpathians are assumed to be the dominating factor of the studied deposition at the expense of eustatic sea level changes. Provenance studies have proven that the pre-Neogene basement (i.e. the Early Carboniferous clastic “Culmian facies” of the Moravian-Silesian Paleozoic) represents an important source for the conglomerates and sands, which volumetrically dominate in the palaeovalley infill. However, they also showed, that the deposits of the earlier Carpathian Foredeep Basin sedimentary stage (Karpatian in age?) covered the area under study and were eroded and resedimented into the palaeovalley infill.

Colonization by marine organisms such as foraminifers, molluscs, bryozoans, brachiopods and red algae during the Middle Miocene (Early Badenian) transgression near Přemyslovice (Carpathian Foredeep) was initially affected by a cool water current of unclear origin. However, shortly afterwards, fallout of volcanic material caused a total termination of the biota. After this catastrophe, the biota started recolonize the area. The succeeding association, adopted to warm-water input, is characteristic of the climatic optimum during the Early Badenian and is comparable with those of other sections referred to this interval in the Carpathian Foredeep (such as Kralice nad Oslavou, Podbřežice, and Hluchov).