• Dimitar Krenchev Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography, Sofia
  • Rositsa Kenderova Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography, Sofia
  • Simeon Matev Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography, Sofia
  • Nina Nikolova Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography, Sofia
  • Georgi Rachev Sofia University “St. Kliment Ohridski”, Faculty of Geology and Geography, Sofia
  • Martin Gera Comenius University, Faculty of Mathematics, Physics and Informatics, Bratislava



debris flows, geomorphological features, synoptic situations, rainfall


Over the last decades, numerous extreme climate events such as extreme temperatures, droughts, heavy precipitation, and storms associated with climate change have been recorded in many countries, including Bulgaria. As a result, geomorphological hazards such as landslides, debris flows, mudflows, high-speed soil erosion, etc. often occur on the territory of the country. The debris flow is one of the most common hazardous processes in small catchments of the main river basins in Bulgaria. The Kresna Gorge located in the middle part of Struma River valley is a typical area with such processes which often cause the damages to the E79 international highway. The purpose of the present study is to characterize debris flows in Kresna Gorge (southwestern part of Bulgaria) by comparative analysis between the two events (occurred on May 24, 2009 and July 28, 2019). In order to achieve the aim of the study the geomorphological features and flow type of 2019 event were identified and the results were compared with the previous publications which investigated the event on May 24, 2009. In the present paper, the sediments and the type of transportation of the investigated event (July 2019) were determined by grain-size and clast-shape analysis. The impact of weather conditions on debris flow occurrence was shown by the analysis of the synoptic conditions on the day before the event. The results of the study bring to clarifying the geological-geomorphological and meteorological factors for the occurrence of debris flow and are important for geomorphological hazard management.

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How to Cite

Krenchev, D. ., Kenderova, R. ., Matev, S., Nikolova, N., Rachev, G., & Gera, M. . (2021). DEBRIS FLOWS IN KRESNA GORGE (BULGARIA)—GEOMORPHOLOGICAL CHARACTERISTICS AND WEATHER CONDITIONS. Journal of the Geographical Institute “Jovan Cvijić” SASA, 71(1), 15–27.