Buntsandstein magnetostratigraphy from the northern part of the Holy Cross Mountains

Abstract

Lower and Middle Buntsandstein sediments from the northern part of the Holy Cross Mountains (Central Poland) were studied palaeomagnetically. The obtained palaeomagnetic pole fits well to the Early Triassic segment of the stable European apparent polar wander path. This indicates that there were no detectable horizontal tectonic rotations in this part of the Holy Cross Mountains after the Early Triassic. In the lowermost part of the Buntsandstein sequence (the A0 and A1 units) the basal Triassic normal polarity zone was identified, whereas a reversed polarity dominates in the youngest rocks of the studied sections. This predominantly reversed part can be correlated with the Pomorze Formation (lower part of the Middle Buntsandstein). The correlation of these magnetic polarity records with magnetostratigraphic data from the other parts of the Central European Basin as well as from the Tethyan sections shows that in the studied area, the Permian-Triassic boundary should be placed near the boundary between the Top Terrigenous Series (uppermost Zechstein) and the A0 unit (lowermost Buntsandstein). In the German part of the Central European Basin the Permian-Triassic boundary coincides with the boundary between the Lower and Upper Bröckelschiefer. The Buntsandstein rocks from the localities of Wióry and Sosnowica contain numerous vertebrate tracks. According to the results of magnetostratigraphic correlation they are of Dienerian (Early Triassic) age.