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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.

The medieval fortification of Mașloc, known as the 'Șanțul Turcilor' (Turkish ditch) is one of the best preserved archaeological sites in the Banat region, Romania. To reconstruct the subsurface archaeological features at the Mașloc site we combined three different geophysical methods: magnetometry, ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) and we used SfM (structure-from-motion) to achieve a detailed digital elevation model and an orthophoto mosaic also. Six hectares were investigated by magnetometry in order to define the basic outline of the medieval settlement, which gradually developed around the fortification. Several GPR and ERT profiles were constructed over the ramparts and ditches of the fortification to determine their extent and the internal structure of the ramparts, ditches and the houses within. The interpretation of these profiles shows for the first time the existence of a second ditch around the fortification: this is not visible in the field. The geophysical mapping precisely identifies the dwellings within the site, which shows the spatial organization of the village. Houses were developed along its main street, oriented northeast-southwest (NE-SW), which were constructed using well-established rules and must have been planned by a local administration. Such organization demonstrates the importance of the village in medieval times, due probably to its location near to the road between two important towns: Timișoara and Lipova. The geophysical results now allow us to associate this settlement with the lost Machalaka, an important village mentioned in the medieval documents. The geophysical investigation demonstrates how this method can delineate village boundaries and the planimetry of internal archaeological features.

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The current paper explores the suitability of geomorphons for the automatic extraction of drumlins. To calibrate the geomorphons to the size of drumlins, it is necessary to optimally define the maximum scale of mapping, i.e., the lookup distance parameter (L). Therefore, based on the concept of topographic grain, we introduce a new automated approach for identifying the specific threshold of L (13 cells) and assessing its potential to generate consistent and accurate results in drumlin extraction. Following an object-based image analysis (OBIA) routine, a new method for mapping and detecting drumlins is proposed. The aggregated geomorphons map was employed both as a thematic layer for image segmentation and as a first criterion for the identification of drumlin candidates. The classification results were quantitatively compared with the reference data in order to evaluate the performance of the drumlin classification, by using five additional L values (3, 50, 100, 200, 400 cells). The evaluation revealed that the highest drumlin detection rate of 91.7% was reached at an L value of 13 cells (65 m), while the lowest value of 84.3% was reached at the default value (L-3 cells). We conclude that the use of the automated procedure for the detection of the L value is useful in achieving a rapid computation of geomorphons, which leads to consistent and accurate results in drumlin extraction. A comparison with previous OBIA methods suggests that the proposed approach produced the most accurate extraction of drumlins. K E Y W O R D S digital elevation model, Eberfinger drumlin field, landform mapping, object-based image analysis, sensitivity analysis, topographic grain