Powodziowe procesy erozji, transportu i sedymentacji w Beskidach Zachodnich

Abstract

The author draws the reader's attention to the fact that inundational accumulation occurs not only in valleys where the gradient is slight, but also in incised valleys where the gradients exceed 100‰. The latter valleys were modelled by stone-and-mud streams. The aggradation of valleys brought about a change in the number and location of rock sources at the river bed. During inundation time a highly differentiated material was accumulated: from clays to sediments of anglomerate texture. The whole material in adequate proportions should be considered the contemporary inundational facies in the West Beskidy Mts. Such being the seddmentological situation, it seems objectionable to choose any exposures at random and to consider them as typical, since from different exposures of the same inundational facies one may draw different conclusions on the mode of sedimentation and on the circumstances under which it took place. A common feature characteristic of every tributary is the suspension of valley beds and bottoms currently modelled by inundational waters. In the main valley at inundational time it is the transport which prevails while the course of water stays at the same level, far the erosion curve is nearing equilibrium, whereas in the lower oourse of the lateral valley a strong accumulation brings about the suspension of the bottom of the latera1 valley over that of the main valley.