It has been recently demonstrated that the early‐time portion of the ground‐penetrating radar (GPR) signal, consisting of the direct air and ground wave events, is dependent on the shallow subsurface bulk electromagnetic properties of the material; these properties are strongly controlled by the water content in this material. While several controlled experiments have been conducted to study the effects of water content variations on the antenna–material coupling, they considered a limited range of moisture variations and soil textures. Furthermore, those previous experiments did not consider highly dynamic shallow moisture responses that would be encountered under natural field conditions. For these reasons, general acceptance of this method requires that it be tested in real‐life applications. Our paper evaluates the early‐time GPR technique under natural field conditions where surface roughness, lithology, lateral heterogeneities, vegetation and water content dynamics are not controlled. We assess the capacity of the early‐time amplitude technique over the complete annual cycle of soil moisture conditions at three textural sites. To evaluate the sensitivity of the early‐time amplitudes to subsurface water content variations, we compare the early‐time results acquired using the enveloped amplitude of the first part of GPR signals with the bulk dielectric permittivity obtained from concurrently collected common‐midpoint direct ground wave velocity and gravimetric water content measurements. Our results demonstrate that the early‐time method can yield near‐surface permittivity information that is consistent with that obtained from direct ground wave velocity measurements, and accurate predictions of shallow soil moisture conditions.

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Several factors affect antenna‐soil coupling in a Ground Penetrating Radar (GPR) survey, like surface roughness, lithology, lateral heterogeneities, vegetation, antenna height from the surface and water content. Among them, lithology and water content have a direct effect on the bulk electromagnetic properties of the material under investigation. It has been recently pointed out that the wavelet of the early‐time portion of a radar signal is correlated to the shallow subsurface dielectric properties of a material. This result indicates that some information on such properties can be directly extracted from the analysis of GPR early‐time traces. In the present paper, we use the early‐time GPR signal, in terms of average envelope amplitude computed on the first half‐cycle, to map the near‐surface (few centimetres) lateral distribution of dielectric parameters, induced by changing the shallow water content on a concrete slab. This controlled experiment was specifically designed to study the effect of water content variations on antenna‐material coupling, minimizing the influence of both surface roughness and heterogeneity. The quantitative control of the water in the shallow portion of the slab is performed by using a portable unilateral Nuclear Magnetic Resonance (NMR) sensor, which is able to determine the water content in the material on the basis of the measured proton density. The results show a matching pattern of the physical parameters measured with the two different techniques and a very high degree of linear correlation (r = 0.97) between the radar early‐time signal average amplitude and the intensity of the NMR signal, which is proportional to the proton density, i.e., to the water content. This experiment suggests that the early‐time approach could be used as a fast and high‐ spatial resolution tool for qualitatively mapping water content lateral variations in a porous material at shallow depth, using a ground‐coupled single‐offset antenna configuration and that a quantitative evaluation of the moisture content would require a calibration procedure.

Due to the versatility of the drone, it can be applied in various areas and for different uses and as a practical support for human activities. In particular, this paper focuses on the situation in Italy and how the authorities use drones for the search and rescue of missing persons, especially now that a 10-year plague that has afflicted Italy with a large number of such incidents annually. Knowledge of the current legislation, the implementation of the drone with other instruments, specific pilot training, and experiential contributions are all essential elements that can provide exceptional assistance in search and rescue operations. However, to guarantee maximum effectiveness of the rescue device, they should seriously consider including teams with proven expertise in operating drones and count on their valuable contribution. Besides drones’ capacity to search large areas, thereby reducing the use of human resources and possibly limiting intervention times, to operate in difficult terrain and/or dangerous conditions for rescue teams, remote sensing tools (such as GPR or ground penetrating radar) as well as other disciplines (such as forensic archeology and, more generally, forensic geosciences) can be implemented to carry out search and rescue missions in case of missing persons.

Alabastro listato or fiorito of Hierapolis in Phrygia was a prestigious coloured marble widely used in Roman architecture and decoration. This stone is generally identified in artefacts on autoptic examination, but it may sometimes be confused with alabasters of different provenances. This study describes a simple, but effective, scientific method to contribute to the determination of Hierapolis alabaster. Due to its unique genetic context, it is characterized by a distinctive carbon isotope signature. A comparison between the stable carbon isotope data from this paper and from the literature confirms the uniqueness of the isotopic character of Hierapolis alabaster. Carbon isotopes can ensure a reliably provenance attribution of the alabaster artefacts along with visual recognition by an expert eye. sanctuary for the gods of the Underworld, was built on a hot bubbling spring. The temperature of the water is close to 35°C, and its emergence to the surface, after a long, deep subterranean circulation, is favoured by crustal tectonic discontinuities that act as preferential ascent routes (Dilsiz 2006;Kele et al. 2011).Hot waters also characterized many springs in the Denizli Basin in the past, most of which bordered the north-eastern flank of the valley. This evidence is provided by the late Quaternary travertine deposits that formed at different times over the last 400 kyr and scattered along the borders of the Denizli Basin, punctuating tectonic lineaments (De Filippis et al. 2012).The travertine outcrops in the Denizli Basin can be classed into five morphological types according to Altunel and Hancock (1993a,b): terraced-mound travertine, range-front travertine, fissure-ridge travertine, eroded-sheet travertine and self-built channel travertine. The area's most characteristic landform is the fissure ridge, a term that dates back to 1883, when Hayden used it to describe an elongated mound with a central fissure along its long axis, characterizing the travertine deposition from hydrothermal hot waters rising along fractures in the bedrock. They are characterized by two main structure types that show different dispositions. The first structure is 'bedded', which has the typical aspect of porous, encrusted travertine and is located on the flanks of the ridge. The second structure, called 'banded', is deposited in the fissures and veins, with a massive aspect, coloured to form brown, yellow and white patchy patterns, sometimes translucent and similar to the cave speleothems. Both types were quarried in ancient and modern times, but the latter was greatly appreciated for its colours and aspect in classical times. Its popularity led it to be exported to Rome and used as prestigious coloured marble in Roman architecture and decoration. It was classified by the Roman stonemasons as alabaster and was later dubbed Alabastro fiorito or listato, probably due to 19th-century literature (Corsi 1845).Bruno (2002) reported the possibility that Strabo recorded the arrival of this stone in Rome, along with different coloured stones...