The aim of the research carried out in the upper Czarna Hańcza valley was to explore the characteristics of channel deposits from various ages and to evaluate their significance in the process of drawing conclusions about the fluvial environment. The deposits of the contemporary Czarna Hańcza channel were analysed; the channel itself is tortuous, locally meandering, with small meanders (with the curve radius of 30 to 70 metres). The deposits of the river with large-magnitude meanders were identified using the example of the Potasznia palaeomeanders, with the curve radius of 500 metres. The deposits of the braided sandur river, providing material for both types of younger fluvial deposits, were revealed in the exposures in Potasznia and Sobolewo. An analysis of the deposits' grain size was conducted using the sieve method, and the texture indicator was determined using the Folk and Ward method (1957). To draw conclusions about the environmental dynamics and the manner of transporting deposits on the basis of sedimentological features, the relationship between the average grain diameter - Mz (on the ϕ scale) and standard variation d₁ (sorting) was used, as well as one between the grain diameter - Mz and the first centile of the grain size distribution – C, which, along with larger ones, account, respectively, for 50% and 1 % of the deposit mass (Passega 1956, Passega Byramjee 1964, Mycielska-Dowgiałło 1995). In the relationship between the average grain diameter - Mz and the standard deviation - σ₁ pattern I was better visible in all the examined deposits, in which the thicker deposits were more poorly sorted. According to Mycielska-Dowgiałło (1995), it is a characteristic feature of a dynamie channel environment. Younger series are characterised by lesser differences in the average grain diameter, accompanied by larger variations in the sediment sorting and, at the same time, a poorer degree of sorting (individual channel types represent the lines with a similar ten dency, Mz-σ₁ but having a smaller channel gradient). Pattern II could be discerned only in the current facies deposits (which until naw has not been identified in the bottom deposits of Polish rivers), in which thicker deposits are better sorted. This is channel lag deposits. Also, in the C-M diagram, most of the points representing the examined deposits can be found in field I, comprising deposits transported in traction in an environment characterised by a high dynamie activity. In the case of contemporary channel deposits, the dependence of the deposition conditions on the channel gradient could be easily visible.
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