The genesis and evolution of uvalas in Gajina mlaka paleovalley on the Ku aj mountains

The evolution of Gajina mlaka paleovalley from pre-karstic to current phase reveals the complexity of process of transformation of valleys in karst and formation of fluviokarst uvalas. The creation of river network and formation of the valley of Gajina mlaka are related to successive withdrawal of the Pontiac Sea. Predominance of karstic process over fluvial causes the transformation of fluvial morphology into karstic. The degree of transformation depends on relationship of the intensity between these two opposed processes. Karstification covers all parts of Gajina mlaka valley which are built in karst. Riverbeds are almost completely transformed and dolines are formed along them. In the parts of valleys with more significant lithologic differences, more complex tectonic relationships and different pre-karstic fluvial morphology, larger forms of relief are created by karstic process and they are called uvalas. According to the presented method of genesis and evolution of uvalas it can be concluded that they are clearly morphologically and genetically individualized karst landforms, which negates some contemporary opinions that exclude both the term and form uvala as karstic element of relief.