engleski

Calculating tectonic strain and stress from the sinkhole distribution

The relation between geological structure and landforms has always been an important subject in geomorphology, but, in the last few decades, the plate tectonic theory has strongly increased the interest in this subject. Many researchers have focussed their attention on the influence of active tectonism on landform development. As the style and location of landform development are determined by the type, location and rate of tectonic movements and their associated stress field (Brunsden, 1990) the aim of this work is the determination of the relation between the karstic relief forms and tectonic processes. We wanted to discover to what extent the tectonic movements influence the development of karst relief and in what measure these influences can be studied from relief. Stress has been invoked in explanation of a number of minor forms, developed mainly in granite (e.g. Jennings and Twidale, 1971), but also in other lithological settings. From this, two questions arise : Can the stress and strain be measured from relief ? Can the deformation rate be measured from relief ? The analyses were applied to the Velebit mountain range which is a typical karstic area. It is a part of the Outer Dinarides, which is in turn a part of the Adriatic-Eurasia collision zone. Its numerous specific relief forms and the recent tectonic activity make the Velebit mountain range pertinent for such analyses. In the karstic domain, dolines can be used as a sensitive indicator of tectonic activity. Even if the development of dolines is primarily the consequence of the rock nature and climatic conditions, its spatial repartition is basically determined by the geological structure. The spatial analysis of dolines allows us the measurement of strain and stress to which the studied area has been submitted during recent periods.

karst; doline; Velebit; Croatia

nije evidentirano