engleski

Spatial disposition and morphological properties of bigger karst depression in Croatia

Bigger depressions of different geomorphological, geological and hydrogeological properties represent one of the most important landform in the karst morphology of the Dinarides. Previous geomorphologic classification was mainly based on descriptional analysis of genetical, morphometrical and hydrogeological properties. In order to quantitatively define their morphological parameters the bottom of depressions was cartographically defined, the spatial morphological properties of their bottoms and of their surroundings (till maximally 2 km) was analyzed. In the first phase all the bottoms of bigger depressions have been vectorized from the topographical maps in the scale 1:25 000 and Landsat images. For the spatial analysis of disposition and morphology of depression bottoms the GIS tool of the ArcGIS (ESRI) software package has been used. The morphology of the depression bottoms are expressed through the index of compaction, that is, with flattenes and direction of the longer axes of the standard deviation ellipse. The standard deviation ellipse represents the trend of objects spreading (depression bottoms) through the values of standard deviation of distance of points located on the depression rim, from the point representing the average value of the depression centre. The index of compaction is related to the value of the depression size and to the size which would get the circle circumference of that bottom. The analysis of the depression surroundings includes the inclination of slopes (gradient slope), their expositions, the transversal and lengthwise slope curvature as well as the vertical relief dissection using the surface unit of 1 ha. According to the obtained parameters the morphological classification of depressions was done from which an important correlation between the shape of depressions their lithological and structural properties derive what directly reflect the main cause of their genesis.

karst deppresion; GIS; spatial analysis; morphology; Dinarides

nije evidentirano