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In GPR (georadar) studies, one of the most popular procedures for determining electromagnetic waves propagation velocity in a rock mass is the selection of theoretical hyperbolic time-distance curves and subsequent comparison with the time-distance curve obtained from a GPR measurement. This procedure is based on the model of homogeneous medium, but nowadays the subject of GPR study is often inhomogeneous media, such as horizontally layered media characteristic of loose permafrost zone sediments. The paper presents the findings of studying the formation of hyperbolic time-distance curves of georadar impulses in a horizontally layered medium without taking into account the dispersion and absorption of electromagnetic waves. On the basis of geometrical optics laws, formulas were derived to calculate the shape of the hyperbolic lineup of georadar impulses reflected from a local feature in a multilayer frozen rock mass. On the example of a permafrost zone rock mass containing a layer of unfrozen rocks, the effect of the thicknesses of rock layers and their relative dielectric permittivity on the apparent dielectric permittivity resulting from the calculation of the theoretical hyperbolic time-distance curve was shown. The conditions under which it is impossible to determine the presence of a layer of unfrozen rocks from a hyperbolic time-distance curve are also presented. The established regularities were tested on synthetic georadar radargrams calculated in the gprMax software program. The findings of the theoretical studies were confirmed by the comparison with the results of the analysis of the georadar measurements computer simulation data in the gprMax system (the relative error was less than 0.5%).

In this work, a geophysical characterization of the subsoil of a civil structure corresponding to the basement of a residential complex in Bogotá, Colombia was carried out, using the GPR technique. We were chosen to establish the affectation caused by weeping willow (Salix Babylonica) trees planted near the retaining wall of the structure's foundation and its parking lot platforms. We acquired GPR profiles all throughout the area of the internal part of the basement and the outer retaining wall part. The pieces of equipment used were SIR 4000 and a HS 350 MHz center frequency antenna. The data presented a good and consistent signal. High resolution subsoil images of up to 3m in depth of the area below the parking lots were generated through the analysis of information derived from the processing and interpretation of the data. All of these were compared with information from geotechnical and topographic studies of the area. The results obtained show that the trees' roots are causing scour due to a drying effect of the subsoil, which caused damage to the slab in the parking lot and on the retaining wall. [ABSTRACT FROM AUTHOR]

This study assessed the safety against overturning of an old entrance structure located at the entrance of Lady of Solitude Cemetery (1850) in Belém do Pará/Brazil. A non-destructive technique using ground penetrating radar (GPR) was used to map the existing foundation and the assessment was made by analyzing the action of load on its centroid and comparing the results of the net allowable capacity of the soil with the maximum pressure exerted at the base of the foundation, also, comparing the moment resistance and the overturning moment in terms of the minimum safety factor required. The GPR results revealed the type of shallow foundation with a depth of 1 m; while the geotechnical results showed that there was no tension in contact with the base. The position of the centroid within the column kern resulted in a safety factor 10 times greater than the minimum recommended value.

Определение возможностей применения метода георадиолокации, относящегося к методам малоглубинной геофизики, в сейсмоактивных районах позволит повысить информативность и достоверность результатов, особенно при инженерно-геологических изысканиях для обеспечения сейсмостойкого строительства в геодинамических активных областях, к которым относится Камчатка. Для оптимизации метода георадиолокации необходимо сопоставление и анализ результатов наблюдений в различных геологических условиях. Поскольку метод георадиолокации интенсивно развивается в последние годы, то теоретические исследования в области обработки данных необходимо иллюстрировать многочисленными примерами практического использования георадаров на разных объектах исследования. Цель исследований заключается в создании научно-методической основы метода георадиолокации применительно к Камчатке, включая методику обработки и интерпретации данных, с учетом практического опыта применения на различных объектах. В статье приводятся опыт и особенности работы с прибором георадар «Тритон-М» на территории города Петропавловск-Камчатский. Объектом исследований являются геологические особенности и грунтовые условия территории города Петропавловска-Камчатского, требующие уточнения и детального изучения. Охарактеризованы некоторые результаты георадиолокационного профилирования. Даны рекомендуемые значения параметров измерений при проведении работ. С практической точки зрения самыми важными параметрами георадара являются глубина зондирования (глубинность) и разрешающая способность по глубине. Прибор георадар «Тритон-М» применим для решения геологических задач на территории города Петропавловск-Камчатский, при этом оптимально подобранные значения параметров измерений минимизируют запись помех и дают более точную полезную информацию о зондируемой среде. Для точной интерпретации радарограмм необходимо использовать сведения о геологическом строении исследуемой территории.

Определение возможностей применения метода георадиолокации, относящегося к методам малоглубинной геофизики, в сейсмоактивных районах позволит повысить информативность и достоверность результатов, особенно при инженерно-геологических изысканиях для обеспечения сейсмостойкого строительства в геодинамических активных областях, к которым относится Камчатка. Для оптимизации метода георадиолокации необходимо сопоставление и анализ результатов наблюдений в различных геологических условиях. Поскольку метод георадиолокации интенсивно развивается в последние годы, то теоретические исследования в области обработки данных необходимо иллюстрировать многочисленными примерами практического использования георадаров на разных объектах исследования. Цель исследований заключается в создании научно-методической основы метода георадиолокации применительно к Камчатке, включая методику обработки и интерпретации данных, с учетом практического опыта применения на различных объектах. В статье приводятся опыт и особенности работы с прибором георадар «ПИТОН-3» на территории города Петропавловск- Камчатский. Объектом исследований являются геологические особенности и грунтовые условия территории города Петропавловска- Камчатского, требующие уточнения и детального изучения. Охарактеризованы некоторые результаты георадиолокационного профилирования. Даны рекомендуемые значения параметров измерений при проведении работ. Георадар «ПИТОН-3» — геофизическая аппаратура радиолокационного подповерхностного зондирования. Данный георадар информативен для исследования на большие глубины при решении геологических задач на территории города Петропавловск- Камчатский. Стоит учесть, что теряется информативность верхней части зондируемой среды (более мелкие геологические структуры можно не обнаружить). Для точной интерпретации получаемых радарограмм необходимо использовать сведения о геологическом строении исследуемой территории.

In the laboratory analysis of geological data, a number of problems arise due to the insufficient accuracy of the results. For example, different laboratories may provide different end results for the same samples, which creates a problem. This can lead to unreliable results, which can ultimately reduce the quality of the assessment. Machine learning allows to speed up the processing of radar data, as well as avoid the above-mentioned «misunderstandings». The problem of conducting scientific research at specialized landfills for a comprehensive assessment of the possibilities of using computer technology in the interpretation of georadar profiles is urgent. This makes it possible to objectively evaluate the result of automatic interpretation of georadar data. The several machine-learning algorithms described in the article are designing to improve the analysis and interpretation of data by incorporating various methods for optimizing georadar data processing processes. These methods include regression, classification and clustering. By incorporating these methods of optimizing the processing of georadar data into several machine-learning algorithms, the software can provide a comprehensive analysis and interpretation of the data obtained. This allows for a better understanding of the relationships, patterns and trends in the data, which ultimately leads to more informed decision-making and improved understanding. To improve the understanding of the results, the following quantitative indicators were obtained: correlation coefficient - 0.7072, determination coefficient - 0.5001, all these indicators correspond to these models. The deviation from the regression line is on average 22.37 units. Based on the classification results, the soil was determined to be wet. Errors in the sets do not exceed 1 %. [ABSTRACT FROM AUTHOR]

The use of geophysical techniques can contribute considerably to the advancement and optimization of subsurface surveys, due to the low costs and time effectiveness. Ground penetrating radar (GPR) has great potential to rapidly and non-invasively evaluate soil in sites affected by the Fundão dam collapse, Southeastern Brazil. The objective of this work was to investigate the thickness of the iron ore tailing layer deposited in a stretch of the Gualaxo do Norte River, besides identifying the most efficient electromagnetic frequency for analysis of this type of material. Three antennas (200, 400 and 900 MHz) were used for GPR surveys in three transects. The radargrams were processed with filtering and gain techniques, aiming to improve the signal quality. We could detect three ground reflection zones with different electromagnetic properties, representing, sequentially, the topsoil, the tailing layer, and the C horizon of the original soil, separated by two reflectors representing the boundaries layers. The tailing layer presented an average thickness of approximately 1 m. 200 MHz presented the best results, whose signal reached the greatest penetration depth and detected the entire tailing layer thickness, besides the others layers present. Using field control points, we could observe that the depths obtained with radargrams had 93% of concordance with the actual depths, which is very satisfactory. The results indicate that the 200 MHz antenna is a better option in surveys involving stratification on Technosols constituted by tailings and GPR should be more explored in the evaluation of soil and sediments. [ABSTRACT FROM AUTHOR]

Precise determination of the location of underground utility networks is crucial in the field of civil engineering for: the planning and management of space with densely urbanized areas, infrastructure modernization, during construction and building renovations. In this way, damage to underground utilities can be avoided, damage risks to neighbouring buildings can be minimized, and human and material losses can be prevented. It is important to determine not only the location but also the type of underground utility network. Information about location and network types improves the process of land use design and supports the sustainable development of urban areas, especially in the context of construction works in build-up areas and areas planned for development. The authors were inspired to conduct research on this subject by the development of a methodology for classifying network types based on images obtained in a non-invasive way using a Leica DS2000 ground penetrating radar. The authors have proposed a new classification algorithm based on the geometrical properties of hyperboles that represent underground utility networks. Another aim of the research was to automate the classification process, which may support the user in selecting the type of network in images that are sometimes highly noise-laden. The developed algorithm shortens the time required for image interpretation and the selection of underground objects, which is particularly important for inexperienced operators. The classification results revealed that the average effectiveness of the classification of network types ranged from 42% to 70%, depending on the type of infrastructure. [ABSTRACT FROM AUTHOR]

The study of methods of searching for explosive objects is an important problem, as it allows to determine the effectiveness of the application of each of the existing methods, which is extremely important for the safety of civilians who are in war conditions, and also allows to prevent possible terrorist acts. This article examines three main methods: laser Raman spectroscopy, ground-penetrating radar, and the terahertz search method. Laser Raman spectroscopy is one of the rather promising methods for the study of explosive objects. It is based on the analysis of the spectrum of light scattered after illumination with a laser beam. Each substance has its own characteristic scattered spectra that can be used for its identification. Laser Raman spectroscopy is highly specific and sensitive to the chemical composition of materials, including explosive substances. It can be applied for non-invasive and rapid detection of such substances, even if they are present in large volumes. GPR is another method for finding explosive objects. It uses radio wave radiation to measure the properties of materials and can detect changes caused by the presence of explosive substances. Ground-penetrating radar has high resolution and the ability to penetrate through different layers of materials, which makes it effective in detecting hidden objects. The use of a terahertz signal is also a promising method in the search for explosive substances. It is based on the use of radiation in the terahertz frequency range, which is between the microwave and infrared ranges. This method is characterized by high sensitivity to chemical changes in materials and the ability to detect even very low concentrations of substances. The use of data processing algorithms and artificial intelligence contributes to the development of effective systems for detecting explosive materials. A summary analysis of the latest research and publications indicates the effectiveness and perspective of the methods of terahertz technology, ground-penetrating radar and laser Raman spectroscopy in the detection of explosive objects. These methods are characterized by high sensitivity, specificity and the ability to work in real time. Additional research and development of these techniques can contribute to further improvements in security systems by effectively detecting and removing explosive objects to prevent potential hazards. [ABSTRACT FROM AUTHOR]

Zoogenic impact plays a critical role in stream processes, especially bank stability and resulting channel dynamics. This study focuses on bioturbation by groundhogs (Marmota monax) along the riparian zone of Mill Creek (Bucks County, Pennsylvania, USA). Several complexes comprising at least 32 active burrows (average diameter: 25.9 cm) were geolocated, with morphometric measurements obtained at selected sites. Two networks were imaged using high-frequency 800 MHz ground-penetrating radar (GPR) and included: 1) a grid of parallel 3-m-long transects on the south bank, and 2) an 11-m-long profile on the north bank. Post-processed electromagnetic signal traces (A-scans) comprising 2D radargrams (B-scans) revealed voids as reverse-polarity anomalies (hollow inclined shafts and tunnels), allowing for a general assessment of burrow depth and orientation. At the southern cutbank site, a large burrow had an entrance diameter of 0.3 m and a westerly dip. A sloping tunnel section was detected at ~0.5 m depth, based on the geometry of point-source (transverse) hyperbolic diffractions corresponding to the roof and a floor ‘pull-up’. The second locality traversed three open burrow entrances adjacent to large tree roots. This survey along a tributary channel shows multiple hyperbolics below adjacent openings, with the latter showing the characteristic signal ‘breakout’. GPR data show hyperbolic signatures ~0.3–0.4 m below the ground surface. Along this transect, burrowing activity appears to increase with proximity to the northern bank of Mill Creek. An example of a depth slice (bedding-plane view) from a nearby riverbank demonstrates the potential for 3D visualization (C-scans) of burrow networks using a grid of closely spaced GPR profiles. Groundhog burrows constrain maximum long-term level of the groundwater table and serve as important zoogeomorphic structures in diverse ecotones, including developed landscapes. Abundant evidence of bank slumping, incision, and treefall suggests that burrowing activity likely weakens root systems and enhances groundwater flow, thereby initiating or accelerating geomorphic cascades leading to slope failure.

В статье представлены результаты работы с прибором георадар «ОКО-250» в кратере вулкана Горелый (Камчатка). В мировой практике это первый опыт проведения исследования методом георадиолокации в кратере активного вулкана. В 2010-2011 году на вулкане Горелый регистрировалось непрерывное спазматическое вулканическое дрожание. Периодически из кратера вулкана наблюдалась парогазовая деятельность. В августе 2011 года, когда были проведены полевые работы, сейсмичность на вулкане Горелый продолжала оставаться выше фона. Данная работа является частью исследований, направленных на решение основной цели, которая заключается в создании научно-методической основы метода георадиолокации применительно к Камчатке, включая методику обработки и интерпретации данных, с учетом практического опыта применения на различных объектах. Одна из решаемых задач, затрагиваемая в данных исследованиях, заключается в применение некоторых методов дополнительной обработки результатов зондирования на конкретных объектах исследования для изучения особенностей волновой картины на радарограммах. Представленные в работе методы дополнительной обработки радарограмм позволяют детально проанализировать волновую картину. При этом выбор методов будет зависеть от поставленных целей и решаемых задач.

The Saint-Seurin Church of Bordeaux is a structure continuously modified from the Middle Ages to the present day. It developed from a mausoleum of Late Antiquity, whose masonry was integrated into a crypt beneath the nave of the church. During an archaeological operation conducted there in 2015, Ground Penetrating Radar (GPR) investigations were carried out on the walls of the thick masonry of the chapels located in the crypt and on the floor of the church, in the nave and in the choir. They highlighted the structure of the masonry of the crypt, encompassing those of the Late Antiquity building, and strengthened the hypothesis of the existence of conduits extending from the chapels to the east of the crypt.

Caral stands as the Americas' oldest city, boasting a heritage spanning 5,000 years. Over time, various natural forces have woven a complex geological stratum. To gain a deeper understanding of the Caral civilization, nonintrusive exploration methodologies like ground penetrating radar (GPR) are beginning to be used. This method safeguards the integrity of ancient subterranean remains. A GPR system is in development, tailored to the [200-500] MHz range, employing a 2×2 antenna array with dual polarization. These features enhance resolution without compromising penetration depth. However, using multiple antennas within complex, multilayered environments introduce impedance band constraints and exacerbates antenna coupling issues. This study assesses the coupling of two antenna candidates: the Vivaldi with defected ground structures (DGS) and the log periodic dipole array (LPDA). The scattering parameters show that the LPDA antenna performed better considering measured and simulated data. Cross-polarization exhibited a broader bandwidth in the LPDA antenna, evident in both simulated and measured data. Additionally, a comprehensive comparison of GPR simulations for each antenna type within an 11-level multilayer medium, with different electromagnetic properties, further highlights LPDA. This antenna boasts a 209 MHz bandwidth and a coupling better than -23 dB for the cross-polarization configuration, firmly showing its best performance. [ABSTRACT FROM AUTHOR]

Archaeological excavations at the site of Raevskoe (northwestern Caucasus) have revealed numerous traces of seismic deformations in building structures erected in ancient times. Although only the foundation parts of the buildings and the lower rows of masonry have been preserved, tilts and collapses, extensions and reversals, and ruptures of ancient building structures are clearly visible in archaeological excavations. The most important identified deformation is the horizontal sublatitudinal displacement of the eastern city wall by 1.4 m near the southern tower. The cause for this displacement was movement along a seismogenic fault: a right-hand fault th+at came to the surface within the site at the turn of the 2nd–1st centuries BC as a result of an earthquake with M = 6.8–7.2. The second strong earthquake occurred in the middle of the 1st century AD. In buildings of Roman age destroyed by the second earthquake, besides seismic inertial deformations, there are also small submeridional horizontal breaks in the foundation parts of the masonry: right-hand shifts with an amplitude of the first tens of centimeters. The cause of the second seismic event could be also movements along the seismogenic fault, which is expressed by an erosion–tectonic scarp with a steepness of up to 40° on the left side of the Muskaga River valley and is traced through the settlement. The data can be used to adjust the seismotectonic model and clarify the seismic hazard of the northwestern Caucasus. [ABSTRACT FROM AUTHOR]

In this paper, we present the first results of complex geological and geophysical studies of active tectonics in the northeast of Taymyr that were carried out during the expedition of the Northern Fleet and the Russian Geographical Society in 2020. At the foot of the Byrranga Mountains, a wide zone of active fault-folded tectonic deformations was identified and studied. The general kinematics of displacements is reverse-thrust with signs of shear. The structural style of young tectonic deformations bears a direct resemblance to well-studied structural analogues of the Central Asian seismic belt. The Taymyr seismotectonic zone reveals both spatial and genetic isolation. It has an individual model of the Late Cenozoic geodynamic evolution and modern seismotectonic regime, which differs sharply from the Laptev Sea rift zone adjacent to the east. A complex of geological and geophysical methods showed the high efficiency of application in the Arctic to identify young fault-fold structures, which are potential sources of strong earthquakes. [ABSTRACT FROM AUTHOR]

Purpose: to perform diagnostics using non-destructive testing devices for reinforced concrete lining and soil foundation of the Kryukovskoe reservoir dam for its technical condition assessment. Materials and methods. The materials for the study were the data of a visual survey of the Kryukovskoe reservoir, the hazardous areas, where the instrumental control by non-destructive methods was performed, were identified. Later the hazardous areas were examined in detail for the presence of defects and damage. In the course of research, an instrumental survey of the reinforced concrete lining of the Kryukovskoe reservoir was carried out in problem areas 12 km long by the Oko-3 georadar. When processing the obtained data, there is a possibility of three-dimensional visualization of the parameters of the medium under study and the attributes of the wave field. At the same time, the soil foundation of the dam was surveyed by a high-frequency detector Nokta Invenio Smart, in real time using the functions of a geoscanner, a three-dimensional model of the studied section of the soil foundation is modelled, displaying the geometric characteristics of hidden cavities and soil softening. Results. Diagnostics of the technical condition of the reinforced concrete lining and soil foundation of the dam of the Kryukovskoe reservoir was performed. The abutments of earthen structures to concrete ones, the state of temperature-settlement joints of concrete and reinforced concrete structures that could affect stability were examined. Radargrams of soil foundation subsidence locations, formed as a result of the accident and removed during the dam reconstruction, were obtained. Conclusions. On the basis of the conducted studies it was defined that the reinforced concrete lining of the reservoir dam is, in general, in a satisfactory condition and serves its functional purpose. Diagnostics of the dam foundation showed the need to strengthen the stability of the structure.

A diverse quite of vertebrate traces covers beach, aeolian, and bay-side (deflation flats) surfaces along the NW Black Sea coast of Ukraine. These include avian, ungulate, and canid footprints, as well as mammal burrows (length >5 cm; depth ~2 cm). The preservation of biogenic structures is enhanced by rapid burial (low-energy sedimentation or event deposition), algal mat formation, and salt encrustation. Continuous high-frequency (800 MHz) ground-penetrating radar (GPR) imaging aided in visualizing subsurface sections of an active burrow complex within a beach-dune ridge. Images near an active fox burrow captured distinct subsurface anomalies (point-source hyperbolic diffractions) in the upper aeolian section above the water table. Unfilled tunnel sections are easily distinguished from buried roots and other targets based on signal velocity and polarity reversals relative to air-to-sediment response at the ground surface. The diffraction geometry (angle) is related to signal velocity, providing valuable information about relative saturation of the overlying substrate. Decimeter-scale deformation of shallow reflections may be attributed to tracking surfaces, with similar examples found immediately below modern surfaces affected by anthropogenic trampling. It is likely that muddy lagoonal tracking surfaces may be preserved under layers of sand (overwash or aeolian deposition) and, following saltwater expulsion, may be recognized in geophysical images as clear deformed paleo-surfaces. Heavy-mineral concentrations (e.g. magnetite-rich sand) are common for beach and dune horizons that have undergone reworking and such anomalies often accentuate physical and biogenic deformation structures. Due to moderate-to-high fraction of ferri- and paramagnetic minerals, these anomalies are also well-expressed in GPR images due to its electromagnetic signal response. A conceptual framework of trace preservation potential (taphonomy) and geophysical recognition (GPR) suitability is proposed for this coastal region, with implications to paleo-environmental reconstruction.

Geophysical studies in archaeological areas use effective archeogeophysical methods that offer a more economical, faster and non-destructive solution compared to classical archaeological techniques in investigating the location and geometry of buried cultural heritages. The most common of these are magnetic, ground electric and ground penetrating radar (GPR) methods. In this study, an archeogeophysical study was carried out to display possible buried archaeological remains in the Stadium area of the ancient city of Sillyon, located in the Pamphylia region of Antalya's Serik district, in the middle of Aspendos and Perge. In this context, vertical gradiometric magnetic total field, dipole-dipole twodimensional electrical resistivity and ground radar methods, which are non-destructive methods of archaeogeophysics, were used in the study area. Within the framework of the findings obtained, determinations were made that could guide the excavation works. Magnetic anomaly findings of the stands were obtained in the middle part of the stadium area, and it is thought that there is a water flow path that cuts the area vertically on the north side of the stadium. This study contributes to the historical and archaeological importance of the ancient city of Sillyon. [ABSTRACT FROM AUTHOR]

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The paper describes the research findings on georadar detection of hydraulic fractures in hydrocarbon reservoirs. Numerical and physical modeling enables studying effect exerted by the electromagnetic properties of the created fracture fill and by the properties of the enclosing formation on the coefficient of high-frequency EM wave reflection from the interface. [ABSTRACT FROM AUTHOR]

Stratigraphy is a fundamental classification tool for archaeology on which modern excavation techniques are based, and essentially consists of a sedimentological, pedological and archaeological interpretation of the multiple cultural layers found while digging; this concept can be adopted when studying monumental buildings and, in particular, their hidden parts or elements. The precious and delicate surfaces of monuments need non-invasive techniques such as geophysical methods and in the present article, the use of GPR technique has been exploited through a dataset collected over the nave of the church of San Leonardo de Siete Fuentes in Sardinia. First, the georadar results have been jointly analyzed by means of the B- and C-scans, in which some most significant patterns were detected and analyzed by looking at their signal features over the investigated volume. Following the analysis, elements from the signal attribute analysis and horizon detection and visualization, with a 3D approach, were used. To strengthen the reliability of the GPR results, a thermal infrared survey was simultaneously carried out. Thanks to the integrated geophysical and historical analysis of the monument, the ancient layout of the church has been reconstructed and other targets of potential archaeological interest identified [ABSTRACT FROM AUTHOR]

Coastal archives of changing hydrometeorological conditions include mineralogical anomalies, such as heavy-mineral concentrations (HMCs) of variable thickness and intensity, which contain varying ferrimagnetic (e.g., magnetite) fractions. As an effective alternative to laborious mineralogical and granulometric analysis, we present the first set of bulk-volume low-field magnetic susceptibility (MS) databases from beach and dune lithosomes in the Western Estonian archipelago: Harilaid cuspate foreland (westernmost Saaremaa Island) and Tahkuna strandplain (northernmost Hiiumaa Island). Readings were conducted both in situ from trench walls and on core subsamples. At the Tahkuna site, late Holocene beach ridges reveal substantially lower values: quartz-dominated dune sequences grade from 5–20 μSI downward to diamagnetically dominated (−1–7 μSI) beach facies. Values are higher (20–140 μSI) in historically reactivated parabolic dunes that are encroaching southward over the strandplain. At the Harilaid site, four beach dune ridges (height: 2–3 m) that span the past 250–300 years show a general increase in mean MS from 320–850 μSI with decreasing age, with peaks of 1000–2000 μSI below the dune crests (depth: ~0.3–0.6 m) likely related to contemporary wind acceleration during ridge aggradation. The highest mineralogical anomalies range from 2000–5500 μSI in the historic dune sections and exceed 8000 μSI along the actively eroding upper-berm segments, typical of HMCs generated by moderate storms. MS anomalies are likely correlated with high-amplitude electromagnetic signal responses in georadar records and provide useful information for optical luminescence sampling strategies. Our study demonstrates that magnetic susceptibility trends provide a useful means of rapidly assessing relative temporal changes in overall wave/wind climates, help identify and correlate discrete anomalies related to extreme events, serve as local beach/dune boundary indicators, and represent potentially quantifiable paleo-energy indices. [ABSTRACT FROM AUTHOR]

As part of the activities within the Living Danube Limes project (INTERREG PROGRAM), geophysical research was conducted in the area of the village of Kopačevo in Baranja. The survey was carried out by the Ludwig Bolzman Institute from Vienna (Austria) in collaboration with the Institute of Archaeology. The survey covered 2.4 hectares in and around Kopačevo. [ABSTRACT FROM AUTHOR]

The traditional identification of the ancient port of Ilici with the current town of Santa Pola in Alicante (Spain) has been based on a small number of punctual, unconnected, and too partial archaeological interventions. Since 2017, a program of geophysical surveys has been performed with a Stream X model multi-channel georadar IDS. This program has been focused mainly on the so-called Mercado de Viguetes, an area in which archaeological excavations have hardly been carried out. The geophysical surveys have allowed us to draw part of the urban fabric of the central core of the Portus Ilicitanus, revealing a set of structures that can be assimilated into a port area: warehouses, houses, open spaces, and decantation basins to produce salted fish, and the probable eastern boundary of the complex identified with the port dock. Altogether, two predominant alignments can be assimilated into the Early Imperial and Late Imperial construction phases. Non-invasive archaeological methodologies have become the main resource for archaeological analysis and heritage protection in view of the current impossibility of carrying out archaeological excavations in this area of Santa Pola. [ABSTRACT FROM AUTHOR]

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Sand is one of the most abundant, naturally occurring materials in many parts of the world, which is used in local rural areas in infrastructure projects such as in the construction of low volume paved and unpaved road layers due to their availability at low cost and scarcity of other suitable construction materials. Several geotechnical solutions for sand stabilization have been undertaken to improve their properties in order to overcome erosion, failure of pavements under traffic loading, embankments, cuts and excavations caused by failures of sand structure. In this investigation, bentonite clay–water slurry was used due to its cohesive and eco-friendly nature to improve sand strength by the means of manual injection in the laboratory and pilot scales. Sand was stabilized using variation of bentonite clay contents, 0%, 1%, 2%, 3%, and 4% (by weight of dry sand), at different curing times: 0 days, 1 day, 2 days, and 3 days. Direct shear tests were conducted to determine shear strength parameters for sand before and after stabilization process. Furthermore, a transparent polypropylene box (60 cm × 40 cm × 30 cm) was used in this study as a larger scale for sand stabilization technique by applying manual grouting of bentonite clay–water slurry to the sand mass. A mechanical shaker was used at 100, 200, 300, and 400 rpm for 10 min at each stage to test the stability of sand in addition to using a Scanning Electron Microscope (SEM) to obtain images for stabilized sand and Ground Penetrating Radar (GPR) to scan soil mass before and after stabilization. The test results showed that a slurry composed of 3% of bentonite clay additive with 10.3% added water by weight of dry sand mass are the optimum amounts for the stabilization process, which provides a substantial resistance to shear forces. [ABSTRACT FROM AUTHOR]

The relevance of the work is determined by the fact that no radiowave methods have ever been used to study the water areas of rivers and lakes and their geoelectric sections within the Baikal natural territory (BNT) in winter time. The purpose of the research is to determine the electrical and geometric characteristics of the layered medium "ice – water – bottom soil" and the ice cover of the Selenga River on the BNT in the VLF-LF and VHF radio wave bands according to the data of instrumental radiophysical measurements by GPR and radio impedance methods, including the determination of the structure of the ice crossings over the Selenga River. Using the Selenga River as an example, consideration has been given to the results of combining VLF-LF and VHF methods of electromagnetic diagnostics of a layered medium in a wide range of radio waves (from tens of kilohertz to units of gigahertz). Radio impedance profiling and sounding in the VLF-LF bands with the IPI-300 equipment made it possible to determine the sub-bottom structure of the soil from the change in impedance and geoelectric section. GPR in the VHF band made it possible to differentiate the fine structure of the Selenga River in winter by thickness of snow, ice and water. The sounding involved the use of georadar "Oko-2" with antenna units "Triton" (central frequency 50 MHz), AB-400 (central frequency 400 MHz), AB-700 (central frequency 700 MHz), and AB-1700 (central frequency 1700 MHz). The thickness of ice of the road crossing in the Mostovoy microdistrict of Ulan-Ude city was 0.5–1.2 m – 0.1–0.2 m thicker than that beyond the road crossing. It was found that the presence of snow cover beyond the road crossing prevents the ice mass from freezing. Calibration sounding of ice with borehole drilling yielded ice dielectric constant ε=3.17. The specific electrical resistance (SER) of water from boreholes is 71–74 Ohm·m at a temperature of 1 °C. The methods used complement each other and provide a quantitative description of the object of research. The integration of various methods of radio wave diagnostics provides more detailed information on the structure of the layered medium "ice – water – bottom soil". The obtained results and the developed methods of radio impedance and GPR sounding and profiling of an inhomogeneously layered underlying environment in winter time can be used in engineering and geological surveys in the eastern and northern regions of Russia.

В статье представлены результаты работы с прибором георадар «ОКО-250» с целью уточнения грунтовых условий в центральной исторической части города Петропавловска-Камчатского на юго-западном берегу Култучного озера. Метод георадиолокации выполнен впервые. Важно отметить значимость георадара для выявления содержания влаги и эрозии грунтов. Благодаря полученным данным, появляется возможность принять правильные решения при проектировании объектов строительства.

The results of laboratory experiments that show the capabilities of modern georadars are presented. Analysis of GPR capabilities allowed to propose a new approach to solving the actual problem of detecting subsurface cracks. The proposed method for recording pulse signals and data processing is based on algorithms and software previously developed by the authors. With the help of this method and the experiments carried out, the possibility of agreed solution to the problem of choosing the optimal parameters of the GPR pulsed signals was shown. To confirm the effectiveness of the developed signal processing methods, a series of laboratory experiments were carried out. The new version of the program "GeoVizy-2020" made it possible to increase the efficiency of processing complex impulse signals. To check the adequacy of the results obtained, a method was used, which is based on the procedure for direct measurement of the real layer thickness in laboratory and field conditions and comparison of the data obtained with the results of numerical simulation. As a result, evidence is presented of the advantages of using pulsed signals for assessing layer parameters, searching for subsurface cracks and processing the results of surveys of road surfaces is presented.

Stratigraphy is a fundamental classification tool for archaeology on which modern excavation techniques are based, and essentially consists of a sedimentological, pedological and archaeological interpretation of the multiple cultural layers found while digging; this concept can be adopted when studying monumental buildings and, in particular, their hidden parts or elements. The precious and delicate surfaces of monuments need non-invasive techniques such as geophysical methods and in the present article, the use of GPR technique has been exploited through a dataset collected over the nave of the church of San Leonardo de Siete Fuentes in Sardinia. First, the georadar results have been jointly analyzed by means of the B- and C-scans, in which some most significant patterns were detected and analyzed by looking at their signal features over the investigated volume. Following the analysis, elements from the signal attribute analysis and horizon detection and visualization, with a 3D approach, were used. To strengthen the reliability of the GPR results, a thermal infrared survey was simultaneously carried out. Thanks to the integrated geophysical and historical analysis of the monument, the ancient layout of the church has been reconstructed and other targets of potential archaeological interest identified

There were done multiple geophysical investigations in different environmental conditions by calibrating the acquired data with the direct information from geological survey and/or borehole drillings along Romania. In a previous project during 2021, there were used georadar investigations in the salt mine of Slanic Prahova for outlining and positioning of the fractures and intercalations of clay layers. Considering that the georadar is responding to the electromagnetic conductivity of the geological layers, there was proposed to start a pilot project which to overlap a refraction seismic profile along a georadar profile done previously and to analyze/compare the results. The choice of geophysical methods and the work procedure are carried out according to the international standards in force, ASTM D6429-99 "Standard guide for Selecting Surface Geophysical Methods", ASTM D5777-00 "Standard guide for Using the Seismic Refraction Method for Subsurface Investigation, ASTM 6432-99 "Standard Guide for Using the Surface Ground Penetrating Radar Method for Subsurface Investigation", STAS 1242/7-84 "Geophysical research of the land by seismic methods". [ABSTRACT FROM AUTHOR]

This article proposes to strengthen the connection of data about constructions made underground and what is built above ground for the development of the concept of multidimensional GIS. We emphasize here the importance and need to use GPR (Ground Penetrating Radar) systems for a fast and accurate acquisition of information about underground utility networks and the geological and geotechnical structure of the land, useful information for new construction investments (buildings, roads, highways, subway etc.). Also here is presented a variant of integrating this data in a GIS platform. [ABSTRACT FROM AUTHOR]

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Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article describes the geophysical analyses used to deepen the knowledge of the causes and consequent degradation phenomena present on the entrance loggia and on the Oratory of San Sebastiano in the Santissima Annunziata complex in Florence. The research highlighted the importance of the relationship between architecture and the environmental system in which it is inserted, especially between the environmental characteristics and the pathologies of the structure, and confirmed the cause / effect relationship between construction and urban drainage system. The preliminary studies conducted on the monument, and in particular the diagnostic campaign of the geophysical surveys, specified the characteristics of the ground on which the Basilica of the Santissima Annunziata rests and described the specific problems of the subsoil.

Coastal archives of changing hydrometeorological conditions include mineralogical anomalies, such as heavy-mineral concentrations (HMCs) of variable thickness and intensity, which contain varying ferrimagnetic (e.g., magnetite) fractions. As an effective alternative to laborious mineralogical and granulometric analysis, we present the first set of bulk-volume low-field magnetic susceptibility (MS) databases from beach and dune lithosomes in the Western Estonian archipelago: Harilaid cuspate foreland (westernmost Saaremaa Island) and Tahkuna strandplain (northernmost Hiiumaa Island). Readings were conducted both in situ from trench walls and on core subsamples. At the Tahkuna site, late Holocene beach ridges reveal substantially lower values: quartz-dominated dune sequences grade from 5–20 μSI downward to diamagnetically dominated (−1–7 μSI) beach facies. Values are higher (20–140 μSI) in historically reactivated parabolic dunes that are encroaching southward over the strandplain. At the Harilaid site, four beach dune ridges (height: 2–3 m) that span the past 250–300 years show a general increase in mean MS from 320–850 μSI with decreasing age, with peaks of 1000–2000 μSI below the dune crests (depth: ~0.3–0.6 m) likely related to contemporary wind acceleration during ridge aggradation. The highest mineralogical anomalies range from 2000–5500 μSI in the historic dune sections and exceed 8000 μSI along the actively eroding upper-berm segments, typical of HMCs generated by moderate storms. MS anomalies are likely correlated with high-amplitude electromagnetic signal responses in georadar records and provide useful information for optical luminescence sampling strategies. Our study demonstrates that magnetic susceptibility trends provide a useful means of rapidly assessing relative temporal changes in overall wave/wind climates, help identify and correlate discrete anomalies related to extreme events, serve as local beach/dune boundary indicators, and represent potentially quantifiable paleo-energy indices.

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T’hó –a Mayan city cited in historical documents – has been discovered and is now a topic in current archaeological discussions and research topics due to a joint UNAM and UADY research project. This project encompassed several steps, including the recording of material recovered from the city’s subsoil while monitoring urban infrastructure programs, as well as the study of historical documents and maps and finally verifying hypothesis by using georadar. After surveying almost 17 km of paved streets in downtown Merida, we realized that it was possible to recognize three main deposit layers underlying the area. The uppermost layer showed modern fillings and urban infrastructure, the intermediate layer had pre-Hispanic cultural remains, and the deepest one included limestone bedrock. This study constitutes the first attempt to create a map of the remains underlying downtown Merida City in order to know and preserve its archaeological patrimony.

The characterization of the Monastery of Batalha included the use of the geophysical method of ground-penetrating radar (GPR), a non-destructive and indirect method that provides high-resolution 2D/3D images of the structures to investigate. Owing to the nature and aims of the survey, appropriate measurement grids, acquisition parameters and adapted data processing techniques were used. The GPR survey provided important information about the Monastery foundations, construction and conservation. GPR high-resolution images allowed to locate recent and ancient infrastructures, columns foundations and structures of historical-archaeological interest. The characterization of the Monastery walls was also carried out using GPR on the surface of walls of the Cloister of D. João I and of the Church. These results contribute for the proposal of an inner structure model of the walls. GPR proved to be an efficient and expeditious method that allowed obtaining information to be used in the preservation, recovery and rehabilitation of the Monument.

The traditional identification of the ancient port of Ilici with the current town of Santa Pola in Alicante (Spain) has been based on a small number of punctual, unconnected, and too partial archaeological interventions. Since 2017, a program of geophysical surveys has been performed with a Stream X model multi-channel georadar IDS. This program has been focused mainly on the so-called Mercado de Viguetes, an area in which archaeological excavations have hardly been carried out. The geophysical surveys have allowed us to draw part of the urban fabric of the central core of the Portus Ilicitanus, revealing a set of structures that can be assimilated into a port area: warehouses, houses, open spaces, and decantation basins to produce salted fish, and the probable eastern boundary of the complex identified with the port dock. Altogether, two predominant alignments can be assimilated into the Early Imperial and Late Imperial construction phases. Non-invasive archaeological methodologies have become the main resource for archaeological analysis and heritage protection in view of the current impossibility of carrying out archaeological excavations in this area of Santa Pola.

Archaeologists have long been called on to use geophysical techniques to locate unmarked graves in both archaeological and forensic contexts. Although these techniques—primarily ground-penetrating radar (GPR)—have demonstrated efficacy in this application, there are fewer examples of studies driven by Indigenous community needs. In North America, the location of ancestors and burial grounds is a priority for most Indigenous communities. We argue that when these Indigenous voices are equitably included in research design, the practice of remote sensing changes and more meaningful collaborations ensue. Drawing on Indigenous archaeology and heart-centered practices, we argue that remote-sensing survey methodologies, and the subsequent narratives produced, need to change. These approaches change both researchers' and Indigenous communities' relationships to the work and allow for the inclusion of Indigenous Knowledge (IK) in interpretation. In this article, we discuss this underexplored research trajectory, explain how it relates to modern GPR surveys for unmarked graves, and present the results from a survey conducted at the request of the Chipewyan Prairie First Nation. Although local in nature, we discuss potential benefits and challenges of Indigenous remote sensing collaborations, and we engage larger conversations happening in Indigenous communities around the ways these methods can contribute to reconciliation and decolonization. [ABSTRACT FROM AUTHOR]