Depositional development of the Polish Upper Rotliegend Basin and evolution of its sediment source areas

Abstract

In the Polish Upper Rotliegend Basin three major depositional systems were predominant: fluvial, aeolian and playa. Sedimentary development of the basin has been controlled by two principal factors: climate and tectonics. the latter related to lithospheric extension leading to subsidence and accomodation space development. Within the framework of structural and climatic constraints. the depositional systems have been developing as a complex pattern of mutual interrelationships. Nine main depositional sequences have been described basing on results of sedimentological analysis coupled with a palaeostructural basin model focused on tracing shifts of depocentres. Definition of the sequences enabled further analysis of a sedimentary balance of the basin and an attempt to define presumable sediment source areas. The brief description of the latter areas is presented and it is shown that their changing size and shining directions of a sediment transport considerably influenced deposition in the basin. During early stages of the basin development main source areas have been located in the west and north while later on eastern and southern provenance has become more important. An important role in a sedimentary budget of the basin has been played by periodic transfer zones linking the Central Basin (= Mid-Polish Trough) with peripheral sub-basins located on the Precambrian East European Platform.