Utwory górnokredowe i trzeciorzędowe na obszarze pomiędzy Działoszycami a Jędrzejowem

Abstract

UPPER CRETACEOUS AND TERTIARY FORMATIONS IN THE AREA BETWEEN DZIAŁOSZYCE·AND JĘDRZEJÓWThe area stretching between Działoszyce and Jędrzejów (Fig. 1) constitutes a part of a tectonical unit called the Nida synclinorium. The top formations occurring in this area belong to the Upper Cretaceous and younger Tertiary. The Upper Cretaceous deposits are developed as homogenous opoka, locally with minute intercalations of sandstones. The opoka represents a compact, very hard rock, light grey in colour. Content of calcium carbonate amounts approximately to 50 per cent that of silica is a little lower. Among the accessory components, the pelitic pyrite disseminated throughout the rock, as well as the pyrite in crystals and in concretions are worthy of stress. Lack of flints and a slight admixture of glauconite are characteristic feature here. Intercalations of sandstones or admixture of quartz grains (up to 2 cam in diameter) are typical of the marginal parts of the Upper Cretaceous sedimentary basin, and occur in the north-eastern portion of the Nida synclinorium. The scanty microfauna does not allow too make stratigraphical subdivision, thus the stratigraphy must have been based on microfauna only (Tab. 1). During examinations, the Upper Campian and the Lower Maestrichtian deposits were distinguished. It was also stated that in bore hole Czarnocin a contact between the Upper and the Lower Campian (or the Santonian) deposits exists and that a transition of the Maestrichtian into the Campian may be observed in all the bore holes studied (Fig. 2).