Selected geomorphic method applied to neotectonic studies in the Northern Carpathians

Abstract

A number of geomorphic techniques have been applied to study morphotectonic pattern of the Northern Carpathians. Apart from classical ones, a wide range of morphometric and statistical methods has also been used. Among these, the construction of the base-level, goniobase and isolong maps require most serious consideration. Neotectonic implications can also be drawn from careful analyses of geometries of the valley network. The highest bifurcation ratios are usually confined to areas showing most intensive Quaternary uplift. The same applies to increased drainage density measures and the ratio of first-order valleys to the total number of valleys. Parameters of longitudinal river bed profiles are sometimes indicative of tectonic tendencies. The North Carpathian rivers reveal an eastward increase in order, length and relief, being accompanied by a decrease in the mean river bed gradient. The highest concavity measures express the river profile maturity while the position of inflexion point delimits sectors modelled by erosional and accumuiationai processes. Another opportunity for morphotectonic reasoning is provided by the studies of orientation of principal stress axes, inferred from the drainage pattern. All these techniques should be verified by detailed geological mapping, aided by interpretation of aerial photographs and radar images, as well as by geophysical soundings.