The Racova catchment. Geomorphological peculiarities

Abstract

The Racova Catchment, located within the southern border of the Central Moldavian Plateau is stretching on 32,908 ha. From the range of sedimentary layers, specific to the Moldavian Plateau, the erosion outcrop Middle and Late Miocene (Sarmatian/Serravillian and Maeotian/Tortonian) formations plus the recent Quaternary ones. The sandy-clayey - clayey-sandy Kersonian (Upper Sarmatian) and clayey-sandy - sandy Maeotian strata lie in a general homocline (monocline) structure. The subsequent valley of Racova, through its almost cross orientation against the general S-SE tilt of the geological formations, clearly emphasizes the first order structural asymmetry. This lay down in the local topography by the large double and north-facing cuesta front of Racova developed on the right side of the catchment. At its turn, the left slope of the Racova Valley is pretty heavily dissected by tributaries which sculptured reconsequent or askew subsequent valleys. That’s why it is far away different from the classical shape of a gentle south-looking cuesta back slope. The reconsequent valleys, north-south oriented and some more developed, obsequent valleys, south-north oriented, from Racova cuesta front highlight the second-order morpho-structural asymmetry. That is marked by the presence of lower amplitude cuestas with their west-facing front and the east-looking back slope. The local landforms are typically hilly within this framework of noticeable cuesta extension and small structural-lithological platforms with peripheral position. The prevailing genetic relief type is represented by the sculptural (fluvio–denudational), followed from great distance by the fluvial accumulation and structural-lithologic relief. Besides the large extension of cuestas, the main peculiarities of the study area refer to the following: severe land fragmentation/dissection and almost the even distribution of slopes on both sides of the Racova Catchment, and noticeable prevailing of the valley sides (78.3% of catchment area). On the whole, the cuesta fronts amounts 62% of the slopes area, and two-thirds of the cuesta back slopes are heavily degraded. The structural-lithological plateaus have a reduced and peripheral incidence and the fluvial terraces are preserved on small patches. Based on field data, three compartments with distinct features have been separated.

DOI: 10.15551/lsgdc.v45i0.09