Próba wyjaśnienia genezy spękań ciosowych margli opolskich

Abstract

An explanation of the genesis of the joints in the Opole marlstonesThe joints observed in the Turonian marlstones in the vicinities of Opole are classified into two systems, viz., a system of vertical joints and a system of oblique ones. The joints of the oblique system cross each other along almost horizontal tines. In the slits of the oblique jointing sometimes there appear the tectonic breccias, pieces of which are glued with lateral secretion. In the pieces of breccias oblique microjoints, which follow the oblique joints were found. The strain ellipsoids of both systems of joints are constructed. A comparison of the orientation of their axes shows that the described systems of joints were caused by different stresses. The system of vertical joints is regarded as formed earlier, probably by tension oriented similarly as that which acted contemporarily in the adjacent areas (Cracovian Upland, Sudetes). The system of oblique joints was formed as a result of horizontally acting tension. A supposition that the latter tension was connected with the folding of the Carpathians is expressed.