Measures of the Vertical Size of River Systems as Indicators of Their Formation Conditions: Case Study of Mountains of Crimea and Caucasian Black Sea Coast

The main measure of a river system is commonly accepted to be its catchment area, which determines its main function, i.e., collecting precipitation. However, the river basin also has a volume and a vertical size. The need to take into account the volume of a river basin and to develop the concept of its vertical size (conventionally, “thickness”) stems from both general methodological considerations and the available experience of hydrological studies. A system of new estimates of the “thickness” and volume of a basin is proposed to characterize, in particular, its cut depth, the vertical dissection, the “thickness” of the zone of active water exchange, etc. These characteristics can significantly improve the efficiency of the methods of structural–hydrographic indication in the analysis of erosion–accumulation processes, solid runoff, and, in regions with the obvious predominance of groundwater inflow, in what regards the parameters of water flow. The efficiency of the proposed characteristics is demonstrated in the analysis of river systems developing under contrast geological conditions, i.e., in the Mountain Crimea and in the southern sector of Caucasian Black Sea coast. The extension of the instrumentation, the improvement of the detail and information content of relief analysis can be of universal value and can be widely applied in the Earth sciences.