Dajki neptuniczne w Rezerwacie Przyrody Nieożywionej Bonarka w Krakowie - świadectwo późnokredowych ruchów tektonicznych na Wyżynie Krakowskiej – replika

Józef Wieczorek, Thierry Dumont, Jean-Pierre Bouillin, Barbara Olszewska

Abstract


NEPTUNIAN DYKES OF BONARKA - A TESTIMONY OF THE LATE CRETACEOUS TECTONIC MOVEMENTS IN THE CRACOW UP LAND - REPLY

Summary
In our opinion the arguments presented by Dżułyński for Tertiary (Upper Miocene) age of faults at Bonarka (Fig. 1) are not convincing. The drawings of Bonarka (Fig. 5) published by Książkiewicz [11] and by Gradziński [7] are in agreement with our interpretation of the Late Cretaceous age of the faults. Neptunian dykes (not "clastic dykes"!) described in our article are tectonic fissures filled mainly by well dated Santonian marls which show some signs of primary lamination. A very similar Santonian material was trapped in bioerosional depressions as well as in narrow fissures, both visible on Jurassic surface (Fig. 2-4). The age of epigenetic silification closely related to tectonic fissures is not documented, but it is possible that this silification took place in Late Cretaceous. The Late Cretaceous extension is marked in several places of the Cracow Upland and in other peri-Tethyan regions, which were affected by an important change in plate dynamic during Late Cretaceous.