Comparative study regarding the causes of land instability phenomena in the area of the Getic Subcarpathians

In Romania, as in many other countries of the world, there are areas, more or less extensive, which are naturally prone to landslides. Such an area, with great extension, is represented by the Getic Subcarpathians. In general, this predisposition of the mentioned area to landslides is favored by its geology and hydrogeology, its lithological structure, its morphology, the rainfall regime and to a lesser extent the tectonics of the region. Based on these considerations, in this paper, we have conducted a comparative study aimed at highlighting in a more concrete manner the causes that led to the onset of land instability phenomena recorded in the past 17 years in this area, also taking into account the human activities. For this purpose, we delimited three study areas, corresponding to the counties of Gorj (an area with shutdown mining activities), Vâlcea (area with lignite open-pits in operation) and Argeş (where human actions that can trigger landslides are related to infrastructure constructions, especially by excavation, other constructions, but also deforestation). This approach allows us to draw conclusions about the extent to which human activities amplify the frequency and intensity of land instability phenomena, and which of these activities has the most unfavorable influence.