The article aims to demonstrate how one of the methods of morphotectonic research, particularly the stream length-gradient (SL) index, may be used as one of the indicators of modern tectonic movements in the region of the Kremenets Mountains. The main factor influencing the spatial value of the SL index is the vertical movements of the Earth's crust. SL index is used to study zones of vertical movements of platforms.
For the conducted analysis, thalwegs and watersheds of the second and higher order were taken. The SL index was calculated for 1834 points of the Kremenets Mountains. The constructed map of SL index distribution showed the principal linear and planar areas of the Kremenets Mountains that underwent the Earth's crust vertical movements. As a result, areas along the northwestern escarpment, plateau-like areas of the central part of the studied upland, and the valley of the Viliya River were significantly influenced by tectonic movements. Low values of the SL index are characteristic of the northern part of the escarpment along the Zbytynka River basin, which reflects the greater intensity of erosional processes as a dominant factor.
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