Results of investigations of the discontinuity surfaces in the Lower Kimmeridgian limestones and marls of the south-western Mesozoic margin of the Holy Cross Mts. are reported. Sedimentary discontinuities, indicated by surfaces representing the various stages of the consolidation of the deposit during non-deposition, have been distinguished on the basis of paleoecologlcal and lithological analyses. The evidence now available suggests a very shallow zone of the formation of these surfaces in high-energy marine environment. Breaks in sedimentation were probably connected here with intermittently retarded subsidence.