The dynamics of rock glaciers in marginal periglacial environments are poorly understood, especially in Eastern Europe where the enhanced continentality produces a distinct pattern of periglacial phenomena. Multi-temporal image analysis of high-resolution optical and radar satellite imagery of the Southern Carpathian Mountains, Romania revealed the small dynamic nature and a slow geomorphologic evolution of rock glaciers over a 46-yr period of record . Nine rock glaciers located in glacial cirques and troughs within the central area of Retezat Mountain were included in this study. Overall, the estimated displacement rates are extremely low (i.e., a few cm/year) compared with other active rock glaciers from all over the world. Despite their relative attenuated activity, it appears that Judele, Valea Rea, and Pietrele are still active rock glaciers, but in an evident disequilibrium/imbalance with the actual climate. These findings document the lowest altitude and easternmost active rock glaciers at this

Summary Origins of ancient rockslides in seismic regions can be controversial and must not necessarily be seismic. Certain slope morphologies hint at a possible co-seismic development, though further analyses are required to better comprehend their failure history, such as modelling the slope in its pre-failure state and failure development in static and dynamic conditions. To this effect, a geophysical characterisation of the landslide body is crucial to estimate the possible failure history of the slope. The Balta rockslide analysed in this paper is located in the seismic region of Vrancea-Buzau, Romanian Carpathian Mountains, and presents a deep detachment scarp as well as a massive body of landslide deposits. We applied several geophysical techniques on the landslide body, as well as on the mountain crest above the detachment scarp, in order to characterise the fractured rock material as well as the dimension of failure. Electrical resistivity measurements revealed a possible trend of increasing fragmentation of rockslide material towards the valley bottom, accompanied by increasing soil moisture. Several seismic refraction surveys were performed on the deposits and analysed in form of P-wave refraction tomographies as well as surface waves, allowing to quantify elastic parameters of rock. In addition, a seismic array was installed close to the detachment scarp to analyse the surface wave dispersion properties from seismic ambient noise; the latter was analysed together with a co-located active surface wave analysis survey. Single-station ambient noise measurements completed all over the slope and deposits were used to further reveal impedance contrasts of the fragmented material over in-situ rock, representing an important parameter to estimate the depth of the shearing horizon at several locations of the study area. The combined methods allowed the detection of a profound contrast of 70-90 m, supposedly associated with the maximum landslide material thickness. The entirety of geophysical results was used as basis to build up a geomodel of the rockslide, allowing to estimate the geometry and volume of the failed mass, i.e., approximately 28.5-33.5 million m3.

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Six rock glaciers in the Southern Carpathians have been investigated by means of geoelectrical soundings in order to detect their internal stratigraphy and the existence of frozen sediments. In the case of three relict rock glaciers, the electrical resistivity measurements indicated a typical internal structure. Low resistivity values (<10 kΩm) which are typical of unfrozen fine‐grained materials were obtained, but high resistivity values (25–240 kΩm) measured in the Pietroasa, Ieşu and Pietrele rock glaciers denote the presence of sediments cemented by interstitial ice and ice lenses. Based on the moderate resistivity values, the ice content is probably low to medium in the upper portion of these rock glaciers, that is, above 2040 m. At two sites (Pietroasa and Văiuga rock glaciers), ground surface temperature (GST) evolution was monitored using digital dataloggers. Mean annual ground surface temperature and GST regime throughout the winter were extracted from the recordings and confirmed the probability of permafrost occurrence in Pietroasa rock glacier. In the Ieşu and Pietrele rock glaciers, measurements of bottom temperatures of the winter snow cover were performed in March 2012. Considering the thick active layer, the reduced ice content and the presence of scarce vegetation on their surface it could be assumed that the permafrost exists in marginal conditions in the Southern Carpathians. The ground ice in permafrost is produced by the groundwater freezing or by snow banks buried by coarse angular boulders following large rockfalls.

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