Nowy reper stratygraficzny ordowiku w okolicy Myszkowa

Abstract

A NEW ORDOVICIAN STRATIGRAPHIC REFERENCE POINT IN THE VICINITIES OF MYSZKÓW Summary The knowledge of stratigraphy of Lower Paleozoic rocks forming basement of the Mesozoic at NE margin of the Upper Silesian Coal Basin remains unsatisfactory. Of these, the Silurian are fairly well known whereas a complex of carbonate rocks from the borehole A-4 Mrzygłód was up to the present almost a single stratigraphic reference point of the Ordovician with paleontological record in this region. Paleontological studies on core material of Paleozoic rocks from numerous drillings in this region, carried out by the Geological Institute, made it possible to find a new stratigraphic reference point for the Ordovician. The new section comprises rocks with identifiable faunal remains, occurring at depths from 198 m to 300 m, directly beneath the Triassic in the borehole 45 WB Mysłów (Fig. 2). Within this packet two major units are differentiated: carbonate- clastic formation and that of siliceous shales. The studies solved the question of age of these strata, hitherto interpreted in various ways.