Profil jury i kredy w Raciborowicach koło Krakowa

Abstract

Profile of Jurassic and Cretaceous series at raciborowice near Kraków W Raciborowicach, położonych na NE od Krakowa, nawiercono pod czwartorzędem i miiocenem utwory kredy, a pod nimi malm. Profil kredy podobny, jest do opisanej już poprzednio kredy okolic Krakowa przez swoją litologię, faunę oraz charakterystyczną przerwę, obejmującą koniak. Pod turonem stwierdzono obecność margli kimerydu, a pod nimi gąbkowy wapień skalisty. The bore-hole at Raciborowice (north-east of Kraków) pierced the Quarternary, Miocene, and Cretaceous systems, and entered Upper Jurassic limestones, in which karst forms are present. The Cretaceous is similar to that of the well known Cretaceous exposed in the vicinity of Kraków, and the resemblances are marked in lithology, fauna, and a very characteristic hiatus covering the Coniaeian and partly the Upper Turonian. The Upper Jurassic sediments contain a very poor fauna and it is difficult to establish a detailed stratigraphic division in this series. In- Informational conglomerates, limestones and marls contain a fauna indicating their Astartian — Kimeridgian age. Also the microfauna indicates the Kimeridgian age, and suggests even the presence of the Upper Kimeridgian. The described series is separated by an erosional surface from the underlying „rocky” (biohermal) limestones of Middle and Upper Rauracian age, as indicated by the presence of Septaliphoria moravica (Uhl). It is possible that the uppermost part of the „rocky” limestones containing large light-coloured flints belongs to the Astartian. The described Rauracian „rocky” limestones are identical with the coeval „rocky” limestones exposed in the vicinity of Kraków and Ojców, and there are no traces of influence of the facial region of the Miechów basin described by J. Czarnocki (1939).