The present article is dedicated to the well-known Basarabean paleontologist Vladimir Rosca, to the geologists Anatol Zaharov, Vladimir Sergheev and Eugenia Hiora, with whom the author had collaborated in 1982-1987 during the process of geological system mapping in the Central region of the Nistru River area. During this research the geological limitations of different lithological systems and stratigraphic discontinuity within the region have been determined. As a result of a detailed study of the fauna’s reminiscences of the Inferior and Medium Sarmatium it was determined that this stratigraphic discontinuity - material and geocronological – did not coincide and differ in space. Comparing the litological and paleontological data, it was confirmed that the N1sm1 / N1sm2 stratigraphic discontinuity is crossing over a couple of lithological varieties and is not placed on the limiting surface between them as it is often drawn up by the majority of geologists during the process of the sedimentary systems’ mapping.