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Late Jurassic-earliest Cretaceous evolution of the epicontinental sedimentary basin of southeastern Poland and Western Ukraine

Gutowski J., Popadyuk I. V., Olszewska B.

Geological Quarterly

2005

Vol. 49, No. 1

31–-44

The following Late Jurassic depositional systems have been recognized in the WUkrainian and SE Polish margin of the East European Platform: shelf slope/basin, open shelf, carbonate ramp, siliciclastic shelf, fluvial/playa, deltaic/swamp, restricted marine/evaporate lagoon. Three depositional megasequences have been identified. Their upper boundaries have been dated by means of targeted stratigraphic studies, compilation of existing data and reinterpretation of stratigraphic correlation concepts respectively as: lower Kimmeridgian divisum/hypselocyclum zones boundary, uppermost upper Kimmeridgian and lower Berriasian. Analysis of thickness and depositional system architecture within themegasequences in six regional cross-sections indicates that depocentre was located in the SW margin of the Mid-Polish Trough during Oxfordian and early Kimmeridgian times and propagated in Tithonian time to the Lviv region. This can be explained by changes in the palaeostress field. Approximately N–S oriented extension during Oxfordian and earliest Kimmeridgian times was replaced by approximately NE–SW oriented extension in Tithonian time. The thickness pattern of the megasequences as well as proximity trends of the system tracts within the sequences clearly coincide with the depocentre propagation.

Sequences of the lithofacies and depositional intervals in the Godula Beds of the Polish Outer Carpathians

Słomka T., Słomka E.

Annales Societatis Geologorum Poloniae

2001

Vol. 71, No 1

35-42

The Markov chains procedure was applied to the study on the sequences of lithofacies and depositional intervals in the Godula Beds (Turonian-Lower Senonian) of the Flysch Carpathians. The model (depositional) and modal (a most frequent in profile) diagrams were constructed and corresponding sequences were recognized. It was found that deposition from high-density turbidity currents of variable retardation rates was the dominating mechanism whereas the low-density turbidity currents were rather rare. The newly deposited sediments were commonly eroded by the succeeding, dense currents. Deposition processes were dominated by the two clearly separated environments: channels and depositional lobes. Their systems were subjected to frequent changes due to lateral migration caused by tectonic movements (uplift of cordilleras and subsidence of sea floor) and eustatic changes of sea level.