Deep vs. shallow – two contrasting theories? A tectonically activated Late Cretaceous deltaic system in the axial part of the Mid-Polish Trough: a case study from southeast Poland

The Polish Basin is a part of a trans-European sedimentary basin comprising the Central European Basin System and stretching from Denmark through Germany to southeastern Poland, and even further to the south into Ukraine. It experienced uplift during the Late Cretaceous, which consequently resulted in the inversion of its axial part (i.e., the Mid-Polish Trough) and development into the Mid-Polish Anticlinorium. In many existing paleotectonic interpretations, southeast Poland - i.e., the subsurface San Anticlinorium and the present-day Roztocze Hills - was included in the Mid-Polish Trough during the Late Cretaceous, representing its axial, most subsiding part. This paleotectonic model was the basis for facies and bathymetric interpretations that assumed Upper Cretaceous sediments, deposited close to the axial part of the Mid-Polish Trough (e.g., in the Roztocze Hills), constituted the deepest facies. In recent years, several studies have contradicted this notion. A growing body of data suggests that this area (southeast Poland) was already a landmass by the Coniacian and Santonian - and certainly in the Campanian and Maastrichtian - rather than forming the deepest part of the Polish Basin.