Osady dolnokredowe w okolicach Izbicy w wierceniu Pagórki (Kujawy)

Abstract

LOWER CRETACEOUS SEDIMENTS IN THE REGION OF IZBICA AND IN THE PAGÓRKI BORE - HOLE (CENTRAL POLAND)In recent years, in connection with the exploration of iron ores, there have been undertaken investigations of the Neocomian sediments in the region of Izbica. Tectonically, this region belongs to the Izbica-Kłodawa anticline (Święty Krzyż­Kujawy-Pomorze zach). The Izbica-Kłodawa anticline is situated in the central part of this arch. In its axial part it is bunt of Lias sediments on which, in turn. lie younger members, i. e. Dogger, Malm, Neocomian and Upper Cretaceous.Furthermore, there appear in the Izbica region Zechstein sediments which have pierced through the Lias sediments, forming a salt dome (Fig. 1). Due to this, the Mesozoic deposits lie here at a steep angle, of about 35°. Towards southwest, the·Lower Cretaceous dips underneath thick Upper Cretaceous sediments the latter fill the so-called "Gopło" basin (Fig. 4). It is only south of Sompolno that they rise again, and here we observe a second "Gopło" anticline. On the southeastern flank of this anticline heretofore known solely from geophysical investigations, there has recently been undertaken the deep bore hole Pagórki which pierced the sediments of the Upper and Lower Cretaceous and the upper members of the Purbeckian. In this bore hole, the sediments of the Lower Cretaceous and the Purbeckian dip at a 35° angle too.