Study of Slow Moving Landslide Umka Near Belgrade, Serbia (IPL-181)

Abstract

The IPL project No 181 titled "Study of slow moving landslide Umka near Belgrade" started in November 2012. The study area is located on the right bank of Sava River, 25 km south west of Belgrade, Serbia. The basic objective of the Project was to enable the analysis, correlation and synthesis of data obtained from various phases of investigation of Umka landslide after 35 years of research. Apart from this, the analysis of data from monitoring conducted during certain phases of research was compared with data from automated GNSS monitoring over the last six years, although during numerous investigations various research methods were used for research and monitoring. The project was focused on: analysis of previous detail site investigations and field instrumentation from 1990-2005, analysis of aerial photos and orthophoto images from 1957-2010, analysis of automated GNSS monitoring results from 2010 to end of the Project and analysis of precipitation and levels of the Sava River. Project beneficiaries are local community and local and regional authorities. In this paper we will present results of the proposed project targets performed by Project participants.

Using Historical Aerial Photography in Landslide Monitoring: Umka Case Study, Serbia

“…The "Umka" landslide was formed on the unevenly urbanized hillsides that span between the River Sava, streams of Stepašanica and Duboko, with average terrain slope from 9 • up to more than 25 • (in the zones of landslide main scarps). The watershed passes of the slope, on which the landslide was formed, are 350-1050 m away from the local erosion base of the Sava River, with a maximum height difference of approximately 135 m. The slopes affected by the sliding process are sporadically undulated, with pronounced occurrences of valleys, elevations, secondary scars and depressions that are of the dm-m order of magnitude [17][18][19]. In the wider area of the hilly high grounds of the research area, an intensive sliding process has developed, which has variable dynamics, as well as river and stream erosion.…”

“…Pannonian sediments are represented by argillaceous marls, marls, marley clays and rare interlayers of marl and limestone up to 10 cm thick. The thickness of the Pannonian sediments is from 10 to 170 m. Pont is represented by gray-blue marley and ferruginous clays, siltstones and fine-grained sand, the sediments are up to 10 m thick [17]. The Quaternary is represented by the Pleistocene, built of gravel, sand, clay, conglomerate, sandstone and loess, as well as the Holocene, built of sandy clay, sand and loess [18].…”

Permanent GNSS Monitoring of Landslide Umka

“…[16]. In addition to geotechnical investigations, the dynamics of Umka landslide was investigated by various geodetic survey techniques, among which are aero photogrammetry [17], UAV photogrammetry [10] and automated permanent GNSS monitoring [1,[5][6][7][8][9].…”

“…The observed GNSS monitoring results, as well as the correlations between precipitation and Sava river level with landslide dynamics were presented in numerous publications [5][6][7][8][9]. Despite the numerous interruptions over the period of almost ten years of permanent monitoring (which are expectable due to the system complexity), the dynamic of Umka landslide is successfully determined and analyzed through time [1].…”