Ryfej na obszarze platformy Polski

Maria Wichrowska

Abstrakt


THE RIPHEAN DEPOSITS ON THE POLISH PLATFORM AREA

Summary
The oldest (Upper Proterozoic in age), non-metamorphosed sedimentary formation in Poland occurs on slope of the East-European platform near Lublin and is named "the Podlasie series". It consists of motley sandy deposits intercaleted with rare siltstone and claystone beds. Its approximate thickness and distribution on area of the Wolyń-Polesie Depression (the Lublin region forms its margin) are shown of Fig. 1 but the depth of occurrence of the Riphean deposits and thickness of overlaying Vendian ones - in Fig. 2. P. Rocks of the Polesie series from platform area of eastern Poland were found in 4 boreholes: Kaplonosy IG 1, Niwa 1, Roskosz 1, Busowno IG 1. The wells from the Terebiń area did not reach bottom of the Vendian effusive rock. The litological-petrographical profile of the Kaplonosy IG 1 borehole still exists as the stratotype profile for the Riphean in Poland due to its complete coring and frequent sampling. The complex list of the lithological and mineralogical rock features of the Polesie series there is shown in Fig. 3. Such sedymentological parameters were discussed as: fractional grading, lamination, markers of grain orientation (fabric), deformation phenomena. Approximate sorting was estimated from quartz grain size and frequency: maximum and most common diameter. Such lithological parameters reflected vertical rock changes of colour, matrix type, stage of recrystalization and mineral composition. Other profiles: Niwa 1, Roskosz 1 and Busowno IG 1 were described in similar way. The Riphean deposits from the Lublin area consist of fine and various grained quartz-feldspar sandstones with quartz and/ or clayey-ferruginous matrix. These deposits are: 1 - inland (origined in fluvial environment), 2 – inland (party eolian, formed during seasonal drying of creeks and rivers), 3 - epicontinental (lagunal deposits, composed mainly of fine, well sorted sandstones). Discussed sandstones of the Polesie formation composed the sedimentary transitional complex, participating in rebuilding of structural plan of the platform area and due it they are regared as perspective bodies for oil and gas prospection.