Paper contribution

Weathering properties of rock blocks and rock mass at natural heritage site Devils Town, Serbia

Miloš Marjanović; Ksenija Micić; Zoran Berisavljevic; Dragana Đurić; Dušan Berisavljević; Biljana Abolmasov

Proceedings
EUROCK 2026
Pages
1249-1255
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The Devils Town site in southern Serbia is a protected natural area where selective erosion is at work. More than 200 rock pillars, typically a few meters wide and up to 15 meters high, have formed within frail volcanic tephric and tuffiaceous deposits subjected to long-term weathering. They are composed of pyroclastic matrix and andesitic rock blocks of various sizes, but usually the largest ones are at the highest positions. The landscape is dominated by the pillars that are capped with such blocks, which are few dm to m across, as they offer better protection against the erosion agents, chiefly intensive seasonal rainfall and snow thaw. In this work, some index properties for reconstructing how weathering is distributed throughout the rock mass are determined, using several approaches. These were limited to non-invasive techniques due to the protected status of the site, including in-situ needle penetrometer tests and geophysical seismic profiling, as well as slake durability tests on solid rock samples from surrounding blocks that are equivalent to those atop the protected pillars. The obtained results suggest both zonal weathering into the depth of the rock mass, ranging from 1.0 to 2.5 m, but also some weathering effects in accordance with micro-location conditions and groundwater retention. Rock blocks on the other hand are expectedly relatively resistant to weathering, with slaking index Id2 in a range of 0.96 to 0.97. Long-term weathering effects are also discussed in respect to possible climate change influence, indicating their acceleration in the future. This research contributes to the ongoing DEMONITOR project, and activities of the UNESCO Chair GeoHARM.

Contributors

Authors

  1. Miloš Marjanović University of Belgrade Faculty of Mining and Geology ORCID 0000-0002-9675-1401
  2. Ksenija Micić University of Belgrade Faculty of Civil Engineering
  3. Zoran Berisavljevic University of Belgrade Faculty of Mining and Geology ORCID 0000-0003-3148-9825
  4. Dragana Đurić University of Belgrade Faculty of Mining and Geology
  5. Dušan Berisavljević University of Belgrade Faculty of Mining and Geology
  6. Biljana Abolmasov University of Belgrade Faculty of Mining and Geology

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References

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