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least diffcrentiated Mz values (from —0.6 to 3.3 0) and by a woli sorting. These facts indicate ihat thc hydrodynamic conditions under which transport a tui sedimentation took place did not changc esscntiully, although in this ca*c channel shift was not aocompanied by incision. The latter is typical of meandenng rivcrs.

Channel deposits of thc Younger Subatlantic meandenng river show similar properties in both valleys. These properties are characteristic of deposits the accumulation of which depended on the highly variable current velocities and stream discharges (Mz ■ from —2.1 to 6.3 0). It is noteworthy that samples of sediment from suspension inerease in amount. This fact may bc explained by the overloading of the river with materials derived from both slopes and undermined terrace edges. Furthermore, as incision proceeded conditions were favourable for the sedimentation of fine materials (being similar to the overbank deposits) in different parts of the river channel.

ChanneMag deposits show properties of channel deposits. These constitute the coarsest channel deposit only in the analysed profile.

Overbank deposits in the Wisłoka valley include floodplain deposits dating from the Atlantic period and levee deposits accumulated in the Younger Subatlantic. In the upper Vistula vałley those deposits comprisc levcc deposits belonging to the Younger Subatlantic and floodbasin deposits accumulated outside the levee. The similarity of overbank deposits of differing age in both valleys is noteworthy (Fig. 14B). Such deposits are fine (Mz — 3.6 — 7.4 0) and poorly sorted. The lack of variations in grain sizes and sorting of the overbank deposits forming terrace levels of differing age was previously stated by L. Koutaniemi (1980) and G. R. Brakenridge (1984).

Overbank deposits of the Pleniglacial braidcd rivers rest on thc surfacc of the extensive alluvial fans built up by the Vistula (Chybie sitc) and by thc Biała (Kaniów site). These deposits are clustered between Mz = 3.4 0 and 7.2 0 (Fig. 14B). Sorting is very poor and, locally, poor. Properties are similar to those of the above described ovcrbank deposits of the meandering rivers.

Channel fili deposits in the Wisłoka valley were noted at the sites Brzeźnica A, B, D, Grabiny and Podgrodzie, and in the upper Vistula valley at thc sites Drogomyśl, Chybie and Kaniów. Their sedimentation took place in thc following periods: IPL, PL2, LG, PB —BO and SA2 (age designations are as for Table 1). Distinct differences between deposits dating from various periods of both the Vistulian and the Holocene are lacking (Fig. 14C). However, the twofold division of these deposits due to different conditions of both transport and sedimentation is clearly yisible. The first group a comprises morę coarse--grained deposits (Mz = —0.2 to 4* 3.1 0). As fining proceeds changes from very poor and poor to moderate, and even well sorting occur. Properties are identical with those of the channel deposits in similar fractions. This fact may indicate that either a cutoff or an abandoned channel fragment becamc reoccupied by the river.

The second group of deposits b is characterized by smali diameters (Mz = 3.5 —8.3 0). For the most part, sorting is very poor. Somc coarser samples are poorly sorted. Properties of the above sediments from suspension in the oxbows rcsemble those of the overbank deposits.

Alluvial fan deposits dating from the Atlantic period havc been described