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Regions densely populated with archaeological monuments pose significant challenges for construction investors and archaeologists during the planning stages of major construction projects. Recognising the archaeological potential of these areas is crucial for planning effective rescue excavations, which have become a standard procedure in construction. This study explores the utility of non-invasive prospection techniques, including artefact field surveys, multispectral imaging, and magnetic surveys, in assessing the area chosen for the I/16 Slaný–Velvary road construction. We specifically focused on the contributions these methods make towards understanding the archaeological context of the proposed construction site. The findings from the magnetic survey were compared with the results of actual archaeological excavations. Through manual visual analysis and statistical spatial correlation, we assessed the effectiveness of the magnetic survey. The ability of magnetic survey to locate different types of archaeological objects proved to be dependent on various factors. The variability of the environmental setting, particularly pedological and geological conditions, is essential. However, the modern anthropogenic impact and the very nature of individual archaeological objects, especially their dimensions, also play an essential role. [ABSTRACT FROM AUTHOR]

The western centre of France is one of the richest regions of Western Europe in terms of causewayed enclosures from the Neolithic period. To date, more than 300 such sites have been identified. Most causewayed enclosures in the region range in size from some hectares to over 10 ha. Exhaustive excavation of such sites is rarely performed because such operations are both financially expensive and time intensive. Completing an exhaustive excavation of these sites is also extremely complicated due to their complexity. Recording the most complete possible site plan is a major challenge for optimizing excavation. Traditionally, aerial photography has been the primary method used for delineating causewayed enclosure plans. A magnetic survey can also provide complementary information. Magnetic imaging reveals both enclosure ditches and internal features (pits, postholes, etc.) quickly and with high spatial resolution. At some sites, occupation layers dating from the time of enclosure may be preserved and contain archaeological artefacts or small features in situ. This article proposes a protocol for locating a Neolithic occupation layer inside a Neolithic causewayed enclosure. To locate the areas where this layer is likely to be present, a map of the archaeological potential of the Le Pontet site was produced based on a thickness map of the soil‐sedimentary cover. This map was created by combining an apparent electrical resistivity map, the results of electrical resistivity tomography, an orthophotograph with contrasting cropmarks and the results of dynamic cone penetration tests. To validate the archaeological potential map, an excavation campaign was conducted in 2020 to investigate several sectors; the aim was to prove the presence of the occupation layer and study the pedo‐sedimentary stratigraphy of the site. [ABSTRACT FROM AUTHOR]

The decade of research concentrating on the area of Eastern Slavonia revealed an abundance of large and complex Middle and Late Neolithic sites. It changed profoundly how we perceive Middle and Late Neolithic settlements, including space, size and organization. The vast majority of these sites were detected through aerial reconnaissance and satellite image analysis. The observation of the sites was followed by intensive field surveys, which confirmed their attribution to the Middle and Late Neolithic period by surface finds. On those confirmed sites in the vicinity of Đakovo, Croatia, a magnetic survey was conducted on five sites, and the results confirmed the presence of large-scale Middle and Late Neolithic settlements with complex spatial organization and enclosure(s). The most complex remains so far are the sites Gorjani, Kremenjača and Topole, which we present in this paper, where one or two settlements remain covering an area of 70 hectares which is currently in the process of formal protection as a cultural landscape by the Ministry of Culture and Media of the Republic of Croatia. The special focus of this paper is the application of remote sensing in the detection, archaeological confirmation and protection of the site of Gorjani Topole. [ABSTRACT FROM AUTHOR]

Regions densely populated with archaeological monuments pose significant challenges for construction investors and archaeologists during the planning stages of major construction projects. Recognising the archaeological potential of these areas is crucial for planning effective rescue excavations, which have become a standard procedure in construction. This study explores the utility of non-invasive prospection techniques, including artefact field surveys, multispectral imaging, and magnetic surveys, in assessing the area chosen for the I/16 Slaný–Velvary road construction. We specifically focused on the contributions these methods make towards understanding the archaeological context of the proposed construction site. The findings from the magnetic survey were compared with the results of actual archaeological excavations. Through manual visual analysis and statistical spatial correlation, we assessed the effectiveness of the magnetic survey. The ability of magnetic survey to locate different types of archaeological objects proved to be dependent on various factors. The variability of the environmental setting, particularly pedological and geological conditions, is essential. However, the modern anthropogenic impact and the very nature of individual archaeological objects, especially their dimensions, also play an essential role.

An extensive magnetic survey has been carried out on a large part of the Roman and late antique city of Pollentia (Alcúdia, Mallorca, Spain), combined with ground penetrating radar (GPR) and electric resistivity imaging (ER Imaging) to obtain data for a better understanding of the ancient city. For magnetic measurements, the 7‐probe fluxgate gradiometer array was used. The GPR data were collected by means of a system equipped with two dual‐frequency antenna boxes of 200 and 600 MHz, respectively. The geophysical data provide some new insights into the layout of the city, with the identification of numerous structures in areas that are still unexplored by archaeological investigation. The results fill the gap of previous partial geophysical surveys and show an interesting, unseen image of ancient Pollentia. [ABSTRACT FROM AUTHOR]

Abstract—We have investigated nearly all of the currently available hydromagnetic survey data to study the magmatic structures in the sedimentary basin of the Barents Sea region. We use the modern interpretation techniques to process over 93 000 km profile data of 1995–2017. It was established that north-west striking dyke groups are abundant in the central and northern parts of the basin; in the south part no dykes were found. Magmatic structures in the sedimentary basin are reflected by the local magnetic anomalies of two types—the linear ones sourced by dykes, and mosaic ones associated with the local areas of magmatism. At sea depth of 100–500 m and sediment thickness over 8 km, the dominant depth of the upper edges of the bodies generating anomalies is about 1500 m. The analysis of the magnetic anomalies could help us to outline more exactly the sedimentary structures, the history of the magmatic processes and the tectonic evolution of the Barents Sea Region. [ABSTRACT FROM AUTHOR]

The decade of research concentrating on the area of Eastern Slavonia revealed an abundance of large and complex Middle and Late Neolithic sites. It changed profoundly how we perceive Middle and Late Neolithic settlements, including space, size and organization. The vast majority of these sites were detected through aerial reconnaissance and satellite image analysis. The observation of the sites was followed by intensive field surveys, which confirmed their attribution to the Middle and Late Neolithic period by surface finds. On those confirmed sites in the vicinity of Đakovo, Croatia, a magnetic survey was conducted on five sites, and the results confirmed the presence of large-scale Middle and Late Neolithic settlements with complex spatial organization and enclosure(s). The most complex remains so far are the sites Gorjani, Kremenjača and Topole, which we present in this paper, where one or two settlements remain covering an area of 70 hectares which is currently in the process of formal protection as a cultural landscape by the Ministry of Culture and Media of the Republic of Croatia. The special focus of this paper is the application of remote sensing in the detection, archaeological confirmation and protection of the site of Gorjani Topole.

Over the past decade, the development of unmanned aerial technologies has allowed them to be considered a tool for conducting remote Earth sensing research. The use of such systems is primarily associated with solving geological and archaeological tasks. However, the armed aggression by the Russian Federation contaminated Ukrainian territory at an unprecedented scale, including unexploded ordnance (UXO). It is necessary to check unmanned aerial vehicles (UAVs) can be used to address this issue. An efficient solution can significantly expedite the process of surveying areas for the presence of UXO, minimizing risks to lives and health. The research was conducted at test sites using full-scale models as targets, as well as disarmed mines and other ordnance. Additionally, a magnetic survey was carried out in areas directly affected by combat operations. Overall, within the scope of this work, approximately 30 hectares of territory were surveyed under various shooting modes and conditions. As expected, a high detection rate is characteristic of target objects with a high ferrous metal content. Unfortunately, the widespread use of plastic ordnance with low iron content and the high density of craters blasts create non-target magnetic anomalies, affecting the overall detection. However, with proper planning and shooting modes, the task of detection is partially addressed. Our preliminary results allow us to draw initial conclusions about the effectiveness of the complex and identify issues that require resolution.

Termite mounds are conventionally surmised as one of the best bio-geological indicator for groundwater occurrence in places where they inhibit. Ground magnetic survey was carried out to prove the assumption about termite mounds as an important indicator for groundwater exploration. Occurrences of 18 Termite mounds were mapped using handheld GPS to identify the suitable trend for magnetic survey. After considering all the criteria such as power lines, fences and fracture system, termite mound 2, 12 and 18 were selected in the NNE-SSW trend, and the ground magnetic survey was conducted in ESE-WNW direction which is perpendicular to the trend of the termite mounds using Proton Precession Magnetometer. Totally, 99 samples were collected with 5 m sampling interval and 50 m profile interval over an area of 22 500 sq.m. The magnetic values varied from –7 363 nT to 898 nT with the mean of –331 nT. Processed map of reduction to Equator indicates the presence of NNE-SSW and WNW-ESE magnetic breaks. Analytical signal map designated the presence of magnetic low in the WNW-ESE direction which coincides spatially with the magnetic breaks. The magnetic profile lines have also brought to light the structurally weak zones. Causative body depth range was estimated using power spectrum and Euler method which are from 120 m to 40 m and 100 m, respectively. The present study appreciably brings out the spatial relationship between the termite mounds and the hydro-fractures. This confirms the assertion with regard to termite mounds as an effective tool for groundwater exploration.

After older research (1928) and numerous recent incursions, the Fedeleşeni-Dealul Cânepăriei settlement continues to arouse the interest of specialists, especially due to the unprecedented discoveries made over time. It is precisely these recent pieces of information, the most interesting of which come from the excavation notebook of I. Nestor, unpublished until 2015, that have led to a new campaign of non-invasive investigations in this settlement. The main purpose was to assess the degree of site preservation and to clarify certain planimetric aspects. LiDAR measurements and magnetometer surveys have provided new data about the internal spatial organization and extent of the site. From the analysis of the altitudinal model, it seems that the site was much larger than it is preserved today, and the internal organization is much more complex. Elements of fortification/delimitation, as well as other types of structures (dwellings, pits, ovens), have been documented, especially in the plateau area of the site. [ABSTRACT FROM AUTHOR]

The goal of present study is determining subsurface structural elements by analyzing geomagnetic data sets aiming to examine their impacts on geological surface structures characterizing the western region in Beni-Suef Governorate, Western Desert, Egypt. A land-magnetic survey is conducted by two exceedingly sensitive proton magnetometers to measure the total intensity of geomagnetic field at the region under investigation. The measurements of regional gradients and time variation were applied to get the required reduction of daily variation. The regional expansions of subsurface structural units were obtained after applying the reduction to north magnetic pole (RTP) method to the corrected magnetic data acquired from land-magnetic survey along with Bouguer maps (1:100,000 scale and 1-mGal contouring interval). Regional-residual technique was applied depending on the power spectrum analysis. Moreover, the edge detection approach is conducted to depict the structures and subsurface hidden anomalies. Different handling processes were applied for acquired land magnetic datasets such as Euler deconvolution and trend analysis. The results of current study revealed that four significant structural forces across the N-S, NW–SE, NE-SW, and E-W directions affected the region. Estimating the basement depth was accomplished using a number of spectral analysis techniques. The values of estimated depths are used for creating a basement relief map. Moreover, the achieved results show that depths to the basement at the region under study vary between 2.3 and 4.7 km. [ABSTRACT FROM AUTHOR]

Monchique is a prominent 902 m topographic high in SW Iberia, which stands out in the general flat landscape of southern Portugal. It lies to the north of the Africa-Eurasia plate boundary, which locally accommodates a slow oblique convergence (∼5 mm/yr). Monchique comprises alkaline magmatic rocks of Late Cretaceous age, intruded in a post-rift context. It hosts the most active seismic cluster in mainland Portugal and important hydrothermal activity. This work investigates the relationship between the alkaline intrusion, local seismicity and hydrothermalism. We present magnetic and gravity modeling based on new drone-borne magnetic data and ground gravity data. New magnetic mapping of Monchique shows a ∼ 15 km long dipolar anomaly with 7–8 km wavelength and 2000 nT amplitude. 3D magnetic inversion models the main Monchique intrusion as a high-susceptibility body, 15 km long and 6 km wide, located below the Monchique mountain and extending 5–7 km depth. 2D forward modeling and geological interpretation further support the existence of ENE-WSW oriented dike-like gabbroic bodies that may extend deeper, around which syenite units have later emplaced. We relocate the seismicity using NonLinLoc and a 3D regional tomographic model, and find that earthquakes align along four main lineations that radiate outwards from the intrusion. We also find that most earthquakes cluster between 8 and 18 km depth, below the magmatic intrusion. The b-value at the core of the seismic cluster is higher than at the surrounding region, possibly related to the local hydrothermalism. We present five new focal mechanisms that are compatible with the regional stress field, supporting a regional tectonic control. The emplacement of the Monchique alkaline intrusion left fractures in the lithosphere that currently act as preferred pathways for fluids. In the context of the present-day stress field, the enhanced fracturing and fluid circulation facilitate the localization of small-magnitude earthquakes. • The Monchique magnetic anomaly is mapped with high resolution using new drone data. • The modeled magmatic intrusion body locates at topmost 7 km below surface. • Most of the clustered earthquakes locate underneath the intrusion, at 8–18 km depth. • Gabbro intruded first along ENE-WSW faults, and was later surrounded by syenite. • The intruded faults now host hydrothermal circulation and earthquake clustering. [ABSTRACT FROM AUTHOR]

In the Southern Urals in 2015–2019 research was conducted on the fortified settlement of the Bronze Age Levoberezhnoe (Sintashta II). An asphalt road was drawn through the settlement, during the construction of which about a third of the monument’s area was destroyed. Excavations of the monument have been carried out since 2015. It has been established that the settlement is multi-layered; it functioned in the Late Bronze Age from the turn of the 3rd–2nd millennium BC until the last quarter of the second millennium BC. Detailed magnetic and topographic surveys were performed on the territory that remaining survived the construction of the road. The location of the external moat was reliably determined by linear positive magnetic anomalies. The base of the outer wall of the settlement had a thickness of about 4 m, the width of the outer moat was 2–2.5 m. It was also possible to accurately localize a number of walls of buildings. The settlement had a rectangular shape, inside there were 26 dwellings. As a result of a comprehensive analysis of the data and aerial photographs of the last century, the layout of the entire settlement was reconstructed.

Volcanoes are typical features of the solar system that offer a window into the interior of planets. Thus, their study can improve the understanding of the interiors and evolution of planets. On Earth, volcanoes are monitored by multiple sensors during their dormant and active phases. Presently, this is not feasible for other planets' volcanoes. However, robotic vehicles and the recent technological demonstration of Ingenuity on Mars open up the possibility of using the powerful and non-destructive geophysical tool of magnetic surveys at different heights, for the investigation of surfaces and subsurfaces. We propose a methodology with a view to extract information from planetary volcanoes in the short and medium term, which comprises an analysis of the morphology using images, magnetic field surveys at different heights, in situ measurements of magnetic susceptibility, and simplified models for the interpretation of geological structures. This methodology is applied successfully to the study of different examples of the main volcanic zones of the Iberian Peninsula, representative of the Martian intraplate volcanism and similar to Venus domes, as a preparatory action prior to the exploration of the rocky planets' surfaces. [ABSTRACT FROM AUTHOR]

The Byki complex on the left bank of the Seim River (Desna basin) comprises eight sites, including multilayer ones, differing chronologically and culturally. The dates of key cultural layers are from 21 to 18 thousand BP. Questioning the use of local landscapes by prehistoric people and the reasons for repeated occupation of the area required a paleolandscape reconstruction. For this purpose, a set of methods were applied on a research scale from local (archaeological excavation) to regional (within a radius of several kilometres). The site's position in the regional topography has been studied using GIS methods, for the nearest encirclement of Byki a detailed digital terrain model was constructed. The near-surface stratigraphy was studied by ground penetrating radar (GPR) and magnetic survey, coring and archaeological excavations. This resulted in the creation of a map of natural depressions layout and their three-dimensional visualisation. It was found that by the time people first arrived, the natural relief was a combination of sand dunes and rounded thermokarst sinkholes. The sediments filling the sinkholes indicate the over-watered conditions made them unsuitable for human habitation (the cultural layers do not extend into the sinkholes), but they could provide a source of water. Most of the sites are found on top of an aeolian barkhan. The distance maps showed that the sites' location provided the best visibility in all directions. Thus, this atypical location of Byki sites at significant distances from the nearest rivers can be explained by a combination of several advantages: location on the edge of a valley in terms of distance vision, local topographic diversity that provided comfortable living conditions and possibly a water supply. [ABSTRACT FROM AUTHOR]

The article presents the results of magnetic and ground‐penetrating radar (GPR) research carried out in Old Dongola in northern Sudan in 2018 and 2020, within the framework of a project designed to investigate the transition from Christianity to Islam taking place in the capital of the Nubian kingdom of Makuria. The integrated datasets from the application of two geophysical methods, of which one is the standard magnetic method used on sites in the Nile Valley and the other ground‐penetrating radar, enhanced the archaeological interpretation, focused in this case on a reconstruction of the urban layout of the 16th–18th‐century Funj settlement within the walls of the Dongola Citadel. The magnetic method, the effectiveness of which has gone unquestioned with regard to the study of silt architecture in the Nile valley, was successful in mapping the general outline of the settlement on the Citadel hill and in the quarter north of the walls. The GPR survey (450‐MHz antenna) provided a much more detailed image of the street grid and was much more effective than the magnetic method in tracing the course of mud‐brick walls in a sandy matrix containing baked brick rubble. Verification of the geophysical results through the excavation of selected parts of the Citadel not only satisfied the objectives of the archaeological project, which was to establish the overall street and building layout in the research area, but also confirmed the effectiveness of the two prospection methods applied in combination and the potential of integrated research with the use of the GPR and magnetic methods for the study of mud‐brick and baked brick architecture on settlement sites in Sudan. [ABSTRACT FROM AUTHOR]

Early medieval strongholds are a significant phenomenon in the archaeology of East Central Europe, as they mirror the political and socio‐economic changes occurring towards the end of the Early Middle Ages. This contribution is concerned with the site of Břeclav‐Pohansko (Czech Republic), which graphically illustrates the rise and fall of the Moravian principality during its short existence from the second half of the 9th to the beginning of the 10th century. The site has been systematically excavated over more than 60 years. The excavation work has been accompanied by numerous geophysical surveys. Based on comparing previous knowledge of settlement on the site and the results of magnetic prospection, we evaluated similarities and differences in the central district of the stronghold using statistics and spatial analysis. Upon analysis of the success rate of the applied geophysical method, we present the resulting model of the settlement structure. The results confirm that the structure of the built‐up area in the central district at Pohansko follows an original pattern which has no analogues in the Central Danubian region in the given period. [ABSTRACT FROM AUTHOR]

High-bandwidth magnetic data are normally distorted by ubiquitous 50- or 60-Hz noise from powerlines and similar sources. The powerline noise can be orders of magnitude larger than the magnetic signal from targets and must be culled from data sets prior to interpretation. Suppression of the powerline noise by simple filtering can result in artifacts and an unacceptable reduction in resolution of ground-based and unmanned aerial vehicle magnetic surveys. Removal approaches such as those based on Biot–Savart modeling are sensitive to the estimated position of the powerline systems, in addition to their limited applicability due to the requirement of a DC source. Moreover, the powerline noise in data acquired from a moving platform is inherently nonstationary and removal techniques must be specifically developed with this in mind. We propose a model-based method that does not rely on a priori knowledge of the powerline system by fitting and subtracting a set of sinusoids to the data. These sinusoids are computed on small windows of data, tied together with regularization terms within the fitting process to reduce discontinuities between segments. We further incorporate powerline frequency as a nonlinear parameter, allowing for fluctuations in the fundamental frequency as loads on the power grid change. Through synthetic and field examples, we show that periodic noise can be reliably removed automatically without the need for filtering or significant alterations of the frequency content. Powerline noise is reduced by over 98% in the field example. [ABSTRACT FROM AUTHOR]

A geophysical survey was carried out at Tattapani thermal spring Azad Kashmir to delineate structure, thickness, depth, lithology and migration of hot plumes contaminating fresh water. The study area was investigated by Vertical Electrical Sounding (VES) using schlumberger array at 21 locations arranged in ten profiles to a maximum depth of 500 m and 200 magnetic observations. The extension and tectonic setup of thermal spring was mapped by geoelectrical litho sections, subsurface geological sections (20m, 20-100m and 100-500m) pseudo section, apparent resistivity map, geoelectrical parameters, statistical distribution of apparent resistivity, total magnetic intensity and anomaly map. The data show that Tattapani hot spring is concentrated along the fault line delineated by geoelectrical litho sections and magnetic section with value of -120 nT to -300 nT, total field intensity of 50000-50450 nT and confirm by macro anisotropy (1.0 to 2.7). The geoelectrical lithological section portrays that study area comprises lithological fabric of dolomite (≥400 ohm.m), sandstone (150-200 ohm.m), clay (80-150 ohm.m), Shaley clay (50-80) and shale (≤ 50). The Thermal Plumes (10-70 ohm.m) were pictured by resistivity section and pseudo section at average depth of 30-60 m and showing migration of hot plumes in the North-Eastern direction contaminating fresh water (100-200 ohm.m). The longitudinal conductance (0.95-15 mhos), transverse resistance (20-300 ohm.m2) are seen having maximum value in the North-Eastern and North-Western side of the study area. The study also shows that fresh ground water is mostly concentrated in sandstone (150-200 ohm.m), dolomite (≥400 ohm.m) and lies above the thermal plumes and thus highly prone to contamination due to upwelling of thermal water

Marea/Northern Hawwariya is one of the largest and most important archaeological sites dating between the 3rd century BC and the 8th century AD located at Lake Mareotis in northern Egypt. Even though excavations have been carried out since the end of the 1970s, the settlement is still largely unexplored. To rectify this situation, non‐invasive research has been carried out on 21.5 ha of the site using a precise positioning system and magnetometer measurements. Exact topographic and magnetic maps were prepared based on the data that were obtained. Simultaneously, verification research were carried out, including archaeological excavations, registering surface findings and satellite image analysis. In the south‐eastern part of the site, electrical resistivity measurements were taken as well. This approach allowed for the identification of the densely built areas of the Byzantine and Early Islamic town. On the south‐western side, some magnetic anomalies were registered, following regular patterns with clear linear borders and surrounded by wetlands without clear signs of habitation. On the northern side, the settlement was limited by an artificial coastline, forming straight waterfronts made of stone blocks. As for the town itself, a 260‐m street with adjacent regular built‐up areas was discovered. This regularity points to an order of planning, at least for the Byzantine part of the settlement. Recording of large amplitude magnetic anomalies proves the presence of heavily burnt objects. They may be interpreted as remains of kilns, perhaps used to manufacture amphorae, glass vessels and lime. Electrical resistivity measurements in the south‐eastern part of the site localized cavities in the natural limestone rock uplift. These may have been rock‐cut tombs. Multidisciplinary, non‐invasive research in Marea/Northern Hawwariya allowed for the quick generation of new knowledge on the topography of the site, significantly enriching information on its form and the functions of its various parts. [ABSTRACT FROM AUTHOR]

The set of geophysical methods employed above ground and inside Verteba Cave Eneolithic Trypillian Culture Site (Ukraine) includes magnetic survey, electrical resistivity tomography (ERT), and ground‐penetrating radar (GPR). The above‐ground geophysical study was aimed at the recognition of lateral and vertical distribution of sulfate karst landforms and archaeological targets. In‐cave measurements were made to prospect archaeological remains in loose infill and unknown voids. The round and oval‐shaped magnetic anomalies with dimensions of 10–25 m and maximum intensity of 15–20 nT are caused by old refilled collapse dolines that were discovered over the cave. The magnetic survey proved the absence of Trypillian culture houses on the surface and the presence of buried archaeological objects in the cave. 2D ERT imaging revealed the vertical structure of karstic collapse dolines, the thickness of the sedimentary layer over gypsum, as well as loamy cave infill. ERT was capable of detecting the void in gypsum by resistivity enhancement up to several thousand ohm‐meters. The underground GPR survey of cave walls provided information about possible vertical air−gypsum and loam−gypsum interfaces within the gypsum layer. The prospective areas for future archaeological excavations and the possible location of undiscovered cavities were outlined on the basis of geophysical results. [ABSTRACT FROM AUTHOR]

Volcanoes are typical features of the solar system that offer a window into the interior of planets. Thus, their study can improve the understanding of the interiors and evolution of planets. On Earth, volcanoes are monitored by multiple sensors during their dormant and active phases. Presently, this is not feasible for other planets’ volcanoes. However, robotic vehicles and the recent technological demonstration of Ingenuity on Mars open up the possibility of using the powerful and non-destructive geophysical tool of magnetic surveys at different heights, for the investigation of surfaces and subsurfaces. We propose a methodology with a view to extract information from planetary volcanoes in the short and medium term, which comprises an analysis of the morphology using images, magnetic field surveys at different heights, in situ measurements of magnetic susceptibility, and simplified models for the interpretation of geological structures. This methodology is applied successfully to the study of different examples of the main volcanic zones of the Iberian Peninsula, representative of the Martian intraplate volcanism and similar to Venus domes, as a preparatory action prior to the exploration of the rocky planets’ surfaces.

A new type of livestock enclosure from the Late Bronze Age has been discovered. Stone walls outline a pair of circular or oval areas that may be up to 50 m in diameter. The stone walls are invisible at the surface; they were discovered in north‐western Crimea and only with the aid of remote sensing and geophysical surveys. In the period 2007–2020, over two dozen of these structures were found; none has ever been noted before. The locations of these sites were first suggested in satellite imagery, often as areas with unusually green vegetation. Then, large‐area magnetic surveys delineated the buried stone enclosures, for there was a good contrast between the non‐magnetic limestone walls and the rather magnetic soil. The features can be identified by the unique pattern of the walls: An almost‐complete circular arc that is connected to a full circle or oval. The soil within the features has a high level of urease enzyme activity and a high concentration of thermophilic microorganisms. This suggests the composting of animal dung and plant residues; therefore, these were corrals and the raising of livestock was a part of the economy. Only one of the doubled enclosures is found at most settlements; the livestock were probably owned by all of the inhabitants. Each settlement had several dwellings, and these had earthen basins whose edges were lined with vertical stone slabs. Several small‐area excavations exposed corral walls. Magnetic measurements of the soil and rock were the basis for magnetic models; the calculated anomalies agree with the measurements of the magnetic maps. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) have become a research hotspot in the field of magnetic exploration because of their unique advantages, e.g., low cost, high safety, and easy to operate. However, the lack of effective data processing and interpretation method limits their further deployment. In view of this situation, a complete workflow of UAV magnetic data processing and interpretation is proposed in this paper, which can be divided into two steps: (1) the improved variational mode decomposition (VMD) is applied to the original data to improve its signal-to-noise ratio as much as possible, and the decomposition modes number K is determined adaptively according to the mode characteristics; (2) the parameters of target position and magnetic moment are obtained by Euler deconvolution first, and then used as the prior information of the Levenberg–Marquardt (LM) algorithm to further improve its accuracy. Experiments are carried out to verify the effectiveness of the proposed method. Results show that the proposed method can significantly improve the quality of the original data; by combining the Euler deconvolution and LM algorithm, the horizontal positioning error can be reduced from 15.31 cm to 4.05 cm, and the depth estimation error can be reduced from 16.2 cm to 5.4 cm. Moreover, the proposed method can be used not only for the detection and location of near-surface targets, but also for the follow-up work, such as the clearance of targets (e.g., the unexploded ordnance).

The prospects for expanding the mineral resource base in many countries are linked with the exploration of stranded sites localized at unexplored areas with complex natural and landscape conditions that make any ground survey, including magnetic prospecting, difficult and expensive. The current level of geology requires high-precision and large-scale data at the first stages of geological exploration. Since 2012, technologies of aeromagnetic surveying with unmanned aircraft vehicles (UAV) enter the market, but most of them are based on big fixed-wing UAV and do not allow to substantially increase the level of survey granularity compared with traditional aerial methods. To increase the scale of survey, it is necessary to reduce the altitude and speed of flight, for which the authors develop the methodical and technical solutions described in this article. To obtain data at altitudes of 5 m above the terrain even in a rugged relief, we created heavy multirotor UAVs that are stable in flight and may be used in a wide range of environmental conditions (even a moderate snowfall), and develop a special software to generate flight missions on the basis of digital elevation models. A UAV has special design to reduce magnetic interference of the flight platform; the magnetic sensor is hung below the aircraft. This technology was conducted in a considerable amount of magnetic surveys in the mountainous regions of East Siberia between 2014 and 2016. The results of the comparison between airborne and ground surveys are presented, which show that the sensitivity of the developed system in conjunction with low-altitude measurements can cover any geologically significant anomalies of the magnetic field. An unmanned survey is cheaper and more productive; the multirotor-based technologies may largely replace traditional ground magnetic exploration in scales of 1:10,000−1:1000.

Chromite deposits have long been reported and exploited in Northern Pakistan as a result of the ongoing convergence of Indian and Asian plates. This research work is a study of one such prospect. We used geophysical and geochemical tools such as magnetic susceptibility at seventy-seven observation stations along with fifteen rock samples collected for geochemical studies. Our geochemical analysis reveals a very high value of Fe, Mn, Cu, and Ni in regions of high magnetic susceptibility indicating the possibility of the presence of Magnetite, Chondrite, Copper-pyrites, and Pentlandite Ores. In addition, we also conducted the correlations analysis to investigate the potential association between various geochemical variables including trace elements to evaluate the potential of the ores for economic minerals others than chromite. Our PCs analysis result presents a clear picture that most of the minerals such as Fe, Ni, Co, Cd, Mg, Mn, and Pd are produced by the same source. Our various analyses are in perfect agreement with previous literature indicating the presence of economical mining of Chromite. [ABSTRACT FROM AUTHOR]

Exploring how ancient people created and inhabited specific sites remains a mysterious challenge for archaeologists. The Al‐Khuribah site is one of the most crucial archaeological places in the north‐western part of Saudi Arabia, and its existence is dated from the eighth to the first century bc. The area is characterized by various archaeological remains that engender debate on the interpretation of those remains among the archaeological community. Aerial images, ground magnetic surveys, and excavation results have been integrated in the proposed area for current and future excavation planning. A Google Earth aerial image for the study site revealed that surface pattern characteristics of the site are in the form of remains of adjacent houses with relatively small rooms. Despite composition similarities between the archaeological remains and host sediments, the integrated results of the analysed aerial image and magnetic gradient results showed significant archaeological features that cannot be traced using one method. To complete the interpretation of an archaeological character at a site, the results of the analysed aerial image and magnetic gradient have been evaluated through successive excavation. Overall, the results evidently support the hypothesis regarding the type of occupation of people living close to the religious temple that was excavated in the area earlier. To support such a hypothesis, the archaeological remains, which include various sized kilns, numerous linear wall features, and some of the daily used objects, must be analysed. [ABSTRACT FROM AUTHOR]

In recent years, geophysical methods have been increasingly applied as a preliminary mapping tool to guide archaeological excavations. Despite the reported growing case histories of geophysical prospections for archaeological purposes, direct comparison between expectations arising from the geophysical results and actual findings is not always systematically performed. A critical comparison between pre-excavation geophysical-guided hypotheses and post-excavation archeological evidences is proposed in this work. A test site within the archaeological area of Locri Epizephyrii (Calabria, southern Italy) was chosen for this purpose. An unsurveyed rectangular area (31 × 26 m) was investigated with high-density ground-penetrating radar (GPR) and magnetic profiles. Several anomalous alignments, both compatible and oblique with respect to the orientation of the Greek-Roman city plan, were preliminarly observed in the geophysical results. The use of two different techniques allowed for comparison of anomalous areas, enhancing the likelihood of finding features of significance. Two archaeological soundings were later carried out in the areas showing the most peculiar geophysical anomalies. Several structures revealing the same orientation of the ancient city plan and belonging to at least two different building phases were unearthed from a depth of 15–25 cm below the ground surface. A systematic comparison between geophysical and archeological results was then carried out. In general, walls showing different construction typologies (opus testaceum , opus incertum or opus caementicium) were found to generate similar radar anomalies. Artifacts made with materials similar to the background sandy alluvial deposits were not identified by both geophysical techniques, as in the case of an unearthed channel bank, made of local sandstone blocks. GPR was globally observed to detect buried structures better than the magnetic method, probably due to background geological variables linked to the presence of Fe-rich minerals within the background sediments, generating noisier and scattered magnetic gradient maps. [ABSTRACT FROM AUTHOR]

In 2019, Polish archaeologists took part in an expedition of the Hermitage Museum, led by K.V. Chugunov, in Chinge-Tey cemetery, Tuva (Russian Federation). This paper presents the results of magnetic surveys carried out within the so-called western chain of barrows and around the princely barrow of Chinge-Tey I. This method of non-invasive research is very well suited to the landscape and has produced a significant body of information. Among others, the survey of the western chain identified a stone mantle in barrow 8, which makes it different from other barrows from this group, whose mounds were built of earth. Another important result is the identification of a stone circle surrounding a cult feature (certainly associated with eschatological rituals) known as the northern complex. The presence of the circle came as a surprise for the investigators of the site, as it does not manifest itself at all on the surface of the site. On the other hand, worth noting is one negative result, which nevertheless allows for some conclusions, namely the lack of detectable anomalies connected with one of the tombs in the vicinity of Chinge-Tey I (barrow 15). Despite being clearly discernible in the landscape, and even more evident in LIDAR images, the barrow is invisible on images produced with a magnetometer. This means that one cannot rule out a possibility that other structures undetectable by magnetic surveys may be present within the investigated part of the cemetery. Nevertheless, one cannot but arrive at the conclusion that the results generated by the magnetic research provide significant information concerning the spatial arrangement of the cemetery and are helpful in planning of archaeological excavation. [ABSTRACT FROM AUTHOR]

The use of Unmanned Aerial Systems (UAS), also known as drones, is becoming increasingly important for geological applications. Thanks to lower operational costs and ease of use, UAS offer an alternative approach to aircraft-based and ground-based geoscientific measurements (Colomina & Molina 2014). Magnetic and hyperspectral UAS surveys hold particular promise for mineral exploration, and several groups have recently published studies of magnetic data collected by UAS for such applications (Malehmir et al. 2017; Cunningham et al. 2018), although equivalent studies using hyperspectral data are still rare (Kirsch et al. 2018). Combining both techniques is particularly useful. Magnetic measurements play an important role in mineral exploration, since magnetisation in rocks is mainly associated with magnetite and other iron minerals, which can be used in mapping and targeting of mineral deposits (Dentith & Mudge 2014). Hyperspectral imaging (HSI) is a powerful exploration and mapping technique in areas where the rock surface is well-exposed, and where geological units and mineral compositions can be estimated from spectral features of the electromagnetic spectrum in the visual and infrared range. This paper reports on the setup of UAS multi-sensor systems that can collect both magnetic and hyperspectral data, developed within the EU-funded MULSEDRO project (MULti-SEnsor DROnes). We focus on small, lightweight solutions with take-off weights less than 5 kg. This is because regulations restrict commercial UAS operations in many countries according to take-off weight, flight height and operating range – typically, only operations in the (extended) visual line of sight are allowed. Lightweight systems are also particularly advantageous to support geological field campaigns as they can be quickly deployed to survey areas of interest. Here, we use both a multi-copter and a fixed-wing UAS as both platforms have advantages. Multi-copters can fly at low elevation and speed, allowing them to follow strongly varying topography and collect high-resolution data that are comparable to traditional ground surveys. Fixed-wing UAS reach higher speeds and have longer endurance, such that larger areas can be mapped in a short time – comparable to smaller helicopter surveys. In addition, we have developed a new integrated positioning system (IPS) for UAS use that is not based on GPS. This affords accurate positioning within areas of poor GPS reception, such as mining tunnels and narrow valleys.

The relevance of the discussed issue is caused by the necessity to develop the effective ways of processing and approaches to interpretation of magnetic and lithochemical data in the search for hydrocarbon deposits in geological conditions of the Siberian platform. One of the features of Siberian platform geological section is the extensive development of products of late Permian-Triassic basaltic magmatism. Against the background of sedimentary formations the effusive rocks and intrusive bodies of the basic structure are differentiated by sharp differences in magnetic properties and levels of accumulation of some chemical elements. In general, the areas of epigenetic influence of hydrocarbon deposits are characterized by high contrast in the change of chemical elements content and magnetic characteristics of sedimentary sequence. Rocks of trap formation contribute significantly to the fluctuations of magnetic field and geochemical anomalies and form their own ones, preventing isolation and identification of magnetic and lithochemical irregularities associated with oil and gas accumulations. Therefore, the application of the developed procedures for oil and gas areas with purely terrigenous cover for processing magnetic and lithochemical data requires the changes in division anomalies of epigenetic and magmatic origin. The main aim of the research is to develop the algorithm for processing magnetic and lithochemical data to allocate the areas of epigenetic influence of hydrocarbon accumulations in conditions of wide development of products of the Triassic magmatism in Siberian platform. Research methods. The authors have used the results of high-resolution magnetic survey and lithochemical sampling of surface sediments in Imbinskaya gas-bearing area of the Angara folds area. Results. The authors developed special procedures when applying bandpass filtering of magnetic data by the method of Saxov-Nygaard and differentiating lithochemical field by indicators of dispersion and variance of geochemical spectrum for identification of anomalous variations caused by the influence of dolerite bodies.

Santa Elena, located on Parris Island along the coast of South Carolina, was the first capital, and northernmost permanent settlement, of Spanish La Florida. Over two decades of occupation (ad 1566–1587), five forts were successively built while by ad 1569 a burgeoning Spanish settlement of over 200 people, complete with artisans, farmers, and Jesuit missionaries, flourished. Here, we articulate the results of recent, full‐coverage ground‐penetrating radar and magnetic gradiometry surveys with over 40 years of extant archaeological data to elucidate organizational characteristics of the Spanish settlement at Santa Elena. In particular, we use geophysical data to identify the potential locations of buried Spanish wells across the site. We identify roughly 200 potential well locations and compare these locations to the distribution of Spanish artifacts across the site yielded through a full‐coverage shovel test survey, the arrangement of Spanish structures known from large‐scale block excavations, and the likely position of roadways and house lots. This new data is used to contextualize and refine extant understandings of Santa Elena's town plan while also contributing to a broader research program devoted to exploring Spanish colonial life and settlement in 16th‐century North America (The Santa Elena Landscape Project). As Santa Elena is a National Historic Landmark currently threatened by rising sea levels, this work contributes to an efficient, minimally invasive research program devoted to exploring the Spanish settlement at Santa Elena and to documenting the range of cultural resources present at the site for the purposes of protection and remediation in the context of significant, ongoing shoreline erosion. [ABSTRACT FROM AUTHOR]

The present work deals with ground magnetic investigations of the Wadi Bani Malik area, 40 km from Jeddah city in Saudi Arabia, to delineate the structural settings and demarcate the possible fractures controlling the contaminated flow in the study area. A magnetic survey has been conducted on the up- and downstream areas of the sewage reservoir and filters have been applied to the measured total field, such as reduction to pole (RTP), normalised source strength, tilt angle, and 3D Euler deconvolution to accomplish the goals. Moreover, the Kaczmarz regularisation algorithm was applied to invert RTP data along two selected profiles to magnetic susceptibility depth section to extract magnetic contacts/faults crossing the Wadi. The Wadi is divided into two areas, upstream (Area 2) and downstream (Area 1). The results show that both areas are composed of complex structural trends. In Area 1, magnetic contacts/faults trend mainly in the NE-SW, NNE-SSW and E-W directions, whereas the major trends in Area 2 are NW-SE. The applied filters revealed that in Area 1 the depth to contacts/faults ranges from ~7 m to ~30 m and in Area 2 the depths to contacts/faults are mostly greater than 30 m. Possible subsurface contaminated water flow directions in both areas were deduced from the spatial distribution of these contacts. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of the main faults and many small-scale faults and submarine structures within Gemlik Bay, on the middle strand of the North Anatolian Fault in the southeast of the Sea of Marmara. In order to produce a fault map for the study area and research tectonic structures, magnetic data were obtained using a cesium vapor magnetometer on a total of 30 profiles (340 km) with N-S and E-W orientation within the bay. Diurnal corrections were applied to obtain the necessary minimization of diurnal variations in the magnetic data. Heading correction and micro-leveling corrections were applied to remove small boat effects, and the reduction to the pole method was applied for greater differentiation of the magnetic data. Magnetic data were analyzed using advanced potential field processing techniques. Euler deconvolution technique was applied to define the extension and depth of the determined lineaments. Boundaries of structures in the region were determined using source edge detection, tilt derivative, the tilt angle of the total horizontal gradient amplitude (TAHG), and a novel edge detector based on the softsign function (SF) techniques. In order to reveal the tectonic evolution of Gemlik Bay, the structures obtained from the analysis results were interpreted and a fault map was produced. The results of the study identified the Armutlu Fault in the north, the Gemlik Fault in the east, the Zeytinbağı Fault and Mudanya Fault in the southwest and the Gençali Fault in the south within Gemlik Bay. These five essential faults significantly affected the region tectonically. These faults correlated well with the location of some previously-known major tectonic structures. Moreover, these important faults following the morphology of the bay indicate that Gemlik Bay was opened by a pull-apart basin mechanism. • We define the basement depth of Gemlik Bay using a 2D magnetic model. • This paper presents an investigation into the determination of the structural boundaries of Gemlik Bay using magnetic data. [ABSTRACT FROM AUTHOR]