Inżyniersko-geologiczna charakterystyka mad doliny Wisły

Abstract

ENGINEERING-GEOLOGICAL CHARACTERISTICS OF MUDS IN THE VISTULA RIVER VALLEY Summary The paper presents the results of analyses of properties of muds deposited in valleys of the Vistula River and its selected tributaries. A marked differentiation of the muds was found already in the cours e of field studies. Two major series (I and II) were recognized in the vertical section. The series may be traced in almost all the studied section, regardless the mode of development of a river valley. Laboratory studies confirmed the validity of that subdivision. The two series differ in both lithology and other engineering-geological properties. The series I is represented by deposits of meandering, slowly flowing river. It i• characterized by fine-grained deposits, i.e. those with increased content of clay fraction. Moreover, in comparison with deposits of the series II, the muds are more moist, plastic and compressible. The mud series II corresponds to deposits of wild, braided river with markedly quicker flow of water. This results in higher share of coarse (silt and sand) fractions in the muds and, therefore, differences in their physico-mechanical properties in relation to muds of the series I. The results of the studies implicate that morphogenetic features may be a leading criterior for evaluating lithological and engineering-geological properties of mud deposits.