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The integration of various geophysical methodologies is considered a fundamental tool for accurately reconstructing the extent and shape of a groundwater body and for estimating the physical parameters that characterize it. This is often essential for the management of water resources in areas affected by geological and environmental hazards. This work aims to reconstruct the pattern and extent of two groundwater bodies, located in the coastal sectors of the North-Eastern Sicily, through the integrated analysis and interpretation of several geoelectrical, seismic and geological data. These are the Sant'Agata-Capo D'Orlando (SCGWB) and the Barcelona-Milazzo (BMGWB) Groundwater Bodies, located at the two ends of the northern sector of the Peloritani geological complex. These two studied coastal plains represent densely populated and industrialized areas, in which the quantity and quality of the groundwater bodies are under constant threat. At first, the resistivity models of the two groundwater bodies were realized through the inversion of a dataset of Vertical Electrical Soundings (VES), constrained by stratigraphic well logs data and other geophysical data. The 3D resistivity models obtained by spatially interpolating 1D inverse VES models have allowed for an initial recognition of the distribution of groundwater, as well as a rough geological framework of the subsoil. Subsequently, these models were implemented by integrating results from active and passive seismic data to determine the seismic P and S wave velocities of the main lithotypes. Simultaneous acquisition and interpretation of seismic and electrical tomographies along identical profiles allowed to determine the specific values of seismic velocity, electrical resistivity and chargeability of the alluvial sediments, and to use these values to constrain the HVSR inversion. All this allowed us to recognize the areal extension and thickness of the various lithotypes in the two investigated areas and, finally, to define the depth and the morphology of the base of the groundwater bodies and the thickness of the filling deposits. [ABSTRACT FROM AUTHOR]

Mountains are vital water sources for humans and ecosystems, continuously replenishing lowland aquifers through surface runoff and mountain recharge. Quantifying these fluxes and their relative importance is essential for sustainable water resource management. However, our mechanistic understanding of the flow and transport processes determining the connection between the mountain block and the basin aquifer remains limited. Traditional conceptualizations assume groundwater circulation within the mountain block is predominantly shallow. This view neglects the role of deep groundwater flowpaths significantly contributing to the water, solute, and energy budgets. Overcoming these limitations requires a holistic characterization of the multiscale nature of groundwater flow along the mountain‐to‐valley continuum. As a proof‐of‐concept, we use a coupled groundwater flow and transport model to design a series of numerical experiments that explore the role of geology, topography, and weathering rates in groundwater circulation and their resulting resistivity patterns. Our results show that accumulating solutes near stagnation zones create contrasting electrical resistivity patterns that separate local, intermediate, and regional flow cells, presenting a target for magnetotelluric observations. To demonstrate the sensitivity of magnetotelluric data to features in our resistivity models, we use the MARE2DEM electromagnetic modeling code to perform forward and inverse simulations. This study highlights the potential of magnetotelluric surveys to image the resistivity structure resulting from multiscale groundwater circulation through relatively impervious crystalline basement rocks in mountainous terrains. This capability could change our understanding of the critical zone, offering a holistic perspective that includes deep groundwater circulation and its role in conveying solutes and energy. Plain Language Summary: Mountains are vital water sources for humans and ecosystems, continuously replenishing lowland aquifers through surface runoff and mountain recharge. Quantifying these fluxes and their relative importance is essential for sustainable water resource management. Here, we present a novel approach to characterize the nested nature of groundwater flow along the mountain‐to‐valley continuum by combining flow and transport models and magnetotelluric (MT) geophysical surveys. We assess the approach's potential by creating virtual realities that mimic realistic patterns of subsurface electrical resistivity. Then, using an inverse modeling approach, we test the ability of different MT survey configurations to reconstruct the resistivity fields. Our analysis shows that the accumulation of solutes in subsurface low‐velocity zones (i.e., stagnation zones) results in resistivity fields with enough contrast to image the local, intermediate, and regional groundwater flow cells. While this study is conceptual in nature, we aim to offer a framework for geophysical exploration that can characterize the critical zone without neglecting deep groundwater circulation and its role in conveying solutes and energy. Key Points: We use a coupled flow and transport model to explore the role of deep groundwater circulation in mountain‐to‐valley systemsRegional groundwater circulation conveys significant amounts of water, energy, and solutes through relatively impervious depthsMagnetotelluric surveys can potentially map the resistivity patterns created by the solute concentration patterns within the mountain block [ABSTRACT FROM AUTHOR]

Groundwater potential regions were delineated using Very-Low Frequency Electromagnetic (VLF-EM) and Vertical Electrical Sounding (VES) geophysical techniques. The VLF-EM measurements were taken as fast reconnaissance to delineate shallow conductive features along seven traverses with 10 m station intervals. The data were qualitatively analyzed and indicated zones of hydrogeological relevance, pointing to regions for VES investigations. Thirteen VESs were mapped with 100 m intervals between current electrodes, and the data were processed manually and using WinResist software to generate sounding curves and geo-electric sections that revealed 3 (84.6%) and 4 (15.4%) layers of earth models. The aquifer units were found in the weathered and fractured layers. The subsurface was classified into high, medium, and low groundwater potential regions, with a larger area indicating low prospects. Regions with high potentials had overburden thicknesses above 18 m, while medium and low yields had overburden thicknesses of 13–18 m and below 13 m, respectively.

Visual observation data collected by protected species observers (PSOs) is required per regulations stipulated in Notices to Lessees (NTLs) and geophysical survey Permits (Form BOEM-0328) issued to seismic operators in the Gulf of Mexico (GOM). Here, data collected by certified and trained PSOs during seismic surveys conducted between 2002–2015 were compiled and analyzed to assess utility in assessing marine mammal responses to seismic noise and effectiveness of required mitigation measures. A total of 3,886 agency-required bi-weekly PSO Effort and Sightings reports were analyzed comprising 598,319 hours of PSO visual effort and 15,117 visual sighting records of marine mammals. The observed closest point of approach (CPA) distance was statistically compared across five species groupings for four airgun activity levels (full, minimum source, ramp up, silent). Whale and dolphin detections were significantly farther from airgun array locations during full power operations versus silence, indicating some avoidance response to full-power operations. Dolphin CPA distances were also significantly farther from airguns operating at minimum source than silence. Blackfish were observed significantly farther from the airgun array during ramp up versus both full and minimum source activities. Blackfish were observed significantly closer to the airgun array during silent activities versus at full, minimum source, and ramp up activities. Beaked whales had the largest mean CPA for detection distance compared to all other species groups. Detection distances for beaked whales were not significantly differences between full and silent operations; however, the sample size was very low. Overall results are consistent with other studies indicating that marine mammals may avoid exposure to airgun sounds based on observed distance from the seismic source during specified source activities. There was geographic variability in sighting rates associated with specific areas of interest within the GOM. This study demonstrates that agency required PSO reports provide a robust and useful data set applicable to impact assessments; management, policy and regulatory decision making; and qualitative input for regional scientific, stock assessment and abundance studies. However, several improvements in content and consistency would facilitate finer-scale analysis of some topics (e.g., effort associated with specific activities, observer biases, sound field estimation) and support statistical comparisons that could provide further insight into marine mammal responses and mitigation efficacy. [ABSTRACT FROM AUTHOR]

Tunnel excavation induces the stress redistribution of surrounding rock. In this excavation process, the elastic strain in the rock is quickly released. When the maximum stress on the tunnel lining exceeds the concrete's load-bearing capacity, it causes cracking of the lining. Comprehensive geophysical exploration methods, including seismic computerized tomography, the high-density electrical method, and the ultrasonic single-plane test, indicated the presence of incomplete distribution of broken rock along the tunnel axis. Based on the geophysical exploration results, a carbon-fiber-strengthened tunnel simulation model was established to analyze the mechanical characteristics of the structure and provide a theoretical basis for sensor deployment. Fiber Bragg grating (FBG) strain sensors were used to measure the stress and strain changes in the second lining concrete after carbon reinforcement. Meanwhile, one temperature sensor was installed in each section to enable temperature compensation. The monitoring results demonstrated that the stress–strain of the second lining fluctuated within a small range, and the lining did not show any crack expansion behavior, which indicated that carbon-fiber-reinforced polymer (CFRP) played an effective role in controlling the structural deformation. Therefore, the combined detection of physical exploration and FBG sensors for the structure provided an effective monitoring method for evaluating tunnel stability. [ABSTRACT FROM AUTHOR]

This technical report explains details on the results of the investigation to build a subsurface structural model and a selection of earthquake data at the target site of the blind prediction exercise for "The 6th International Association of Seismology and Physics of the Earth's Interior/International Association of Earthquake Engineering International Symposium on the Effect of Surface Geology on Seismic Motion (ESG6)." The selection process of the target site in the Kumamoto Plain, Japan, in ESG6 was explained with a historical review of the blind prediction tests in the previous ESG conferences. We have collected existing subsurface structural and earthquake data and conducted geophysical and geotechnical surveys in and around the target site to generate important velocity structure and the earthquake data used in the blind test. Microtremor data were obtained in triangular arrays ranging in side lengths from 1 to 962 m, and active surface wave data were derived along a 36-m line at the site. These data were provided for the prediction of a subsurface structural model in the first step of the blind prediction exercise. We also conducted a velocity logging in a borehole to a bottom depth of 39 m at the site and laboratory tests of soil samples from the borehole. We constructed a velocity profile of the shallow and deep sedimentary layers from a combination of the geophysical and geotechnical data at the site, and validated it by comparing the characteristics of the ground motion data from the moderate event. This "preferred velocity model" was provided as a standard model to the participants in the second and third steps of the blind prediction test to predict the earthquake ground motions of a moderate event and the mainshock of the 2016 Kumamoto earthquake. [ABSTRACT FROM AUTHOR]

Today, relatively warm Circumpolar Deep Water is melting Thwaites Glacier at the base of its ice shelf and at the grounding zone, contributing to significant ice retreat. Accelerating ice loss has been observed since the 1970s; however, it is unclear when this phase of significant melting initiated. We analyzed the marine sedimentary record to reconstruct Thwaites Glacier's history from the early Holocene to present. Marine geophysical surveys were carried out along the floating ice-shelf margin to identify core locations from various geomorphic settings. We use sedimentological data and physical properties to define sedimentary facies at seven core sites. Glaciomarine sediment deposits reveal that the grounded ice in the Amundsen Sea Embayment had already retreated to within ~45 km of the modern grounding zone prior to ca. 9,400 y ago. Sediments deposited within the past 100+ y record abrupt changes in environmental conditions. On seafloor highs, these shifts document ice-shelf thinning initiating at least as early as the 1940s. Sediments recovered from deep basins reflect a transition from ice proximal to slightly more distal conditions, suggesting ongoing grounding-zone retreat since the 1950s. The timing of ice-shelf unpinning from the seafloor for Thwaites Glacier coincides with similar records from neighboring Pine Island Glacier. Our work provides robust new evidence that glacier retreat in the Amundsen Sea was initiated in the mid-twentieth century, likely associated with climate variability. [ABSTRACT FROM AUTHOR]

The province of Chimborazo located in the northern Andes of Ecuador presents many intrinsic factors, which contribute to the occurrence of mass movements, leaving in many of the cases registered damages of materials and loss of life. The recent landslide of March 26, 2023, in the Alausí canton is an event of great interest due to the magnitude of the occurred destruction and the corresponding fatalities. Therefore, there are two predominant objectives of the current study, of which the first has been to determine the most relevant characteristics of this mass movement by identifying and analyzing the geomorphology of the recorded slope movement and the lithological units involved, by field work and through geophysical surveys. Secondly, we performed a preliminary study of the possible triggers of the movement by means of the historical analysis of the precipitations during the months of January to March of the last decade and the study of the recent seismic series. However, through the obtained analysis, it is determined that the study site is composed of three distinctive lithological units. The observed mass movement is of the rotational type, as result of the intense rainfall that occurred during the first quarter of 2023, being hereby the most probable triggering factor. This corresponds to a 600% increase in the average monthly rainfall compared to the period from 2010 to 2022. [ABSTRACT FROM AUTHOR]

Graphite is considered to be one of Europe's most critical minerals. It is necessary for the transition from hydrocarbon fuel to electricity due to its use in batteries that power electronic devices and electric transport. In the past, high-quality exposed graphite was found in Norway without today's advanced geophysical and geological methods. Norway is a key destination in Europe for graphite production. With an increasing demand for graphite, there have been efforts to systematically survey the country using modern geophysical and geological methods to find hidden graphite deposits. Among the various geophysical survey methods, electrical and electromagnetic (EM) methods are the first choice for the exploration of graphite due to the material's high electrical conductivity. Airborne surveys are often used to cover a large area for a regional reconnaissance survey to locate the sites with potential mineral deposits before performing ground geophysical and geological surveys. Therefore, frequency-domain helicopter EM (HEM) and airborne magnetic surveys were performed in Northern Norway to locate interesting anomalies which were followed by ground surveys such as electrical resistivity tomography (ERT), charged-potential (CP), self-potential (SP), ground EM, and geological surveys. Some locations were also investigated with drilling and petrophysical core-sample analysis. In this paper, we present helicopter EM and magnetic data, 3D inversion of HEM data, and a successful ground follow-up survey result from the Vesterålen district in Northern Norway. The HEM survey identified previously known and new graphite occurrences, both partially exposed or buried, which were confirmed using ground surveys, drilling, and laboratory analysis of the samples. [ABSTRACT FROM AUTHOR]

The occurrence of geothermal spring not only enhances human health, but also plays a crucial role in generating community's revenue that boosts up the standard living of locals. An endeavor has been made to delineate the prospective areas of geothermal spring in Kon Tum province, Vietnam by the utilization of joint-geophysical techniques. The blended mode as mentioned is opted for its superiority in providing the rapidassesments of temperature in shallow temperature survey, comprehensive understanding the subsurface structure in electrical resistivity tomography in copporating with the validation in well log interpretation. The results found that the overlapping region of high temperature (35°C) region and low resistivity (200 Ωm) is observed in the east in the vicinity of Dlak Bla river, and it probably broadens to the west of the study area. The outcome of geophysical approaches strongly concur with the well log interpretation, revealing the presence of water-bearing zone encountered in fractured granite. The results also corroborated the existence of concealing fault F5 as a branch of the NE-SW fault F2 which is favorable for creating a route to form the geothermal spring. The output of this research could be considered as an intentive consultation for Kon Tum's planners and makers on expanding the investigation and exploitation. [ABSTRACT FROM AUTHOR]

The Italian territory of Sardinia Island has an enormous cultural and identity heritage from the Pre-Nuragic and Nuragic periods, with archaeological evidence of more than 7000 sites. However, many other undiscovered remnants of these ancient times are believed to be present. In this context, it can be helpful to analyze data from different types of sensors on a single information technology platform, to better identify and perimeter hidden archaeological structures. The main objective of the study is to define a methodology that through the processing, analysis, and comparison of data obtained using different non-invasive survey techniques could help to identify and document archaeological sites not yet or only partially investigated. The non-invasive techniques include satellite, unmanned aerial vehicle, and geophysical surveys that have been applied at the nuraghe Nanni Arrù, one of the most important finds in recent times. The complexity of this ancient megalithic edifice and its surroundings represents an ideal use case. The surveys showed some anomalies in the areas south–east and north–east of the excavated portion of the Nanni Arrù site. The comparison between data obtained with the different survey techniques used in the study suggests that in areas where anomalies have been confirmed by multiple data types, buried structures may be present. To confirm this hypothesis, further studies are believed necessary, for example, additional geophysical surveys in the excavated part of the site. [ABSTRACT FROM AUTHOR]

Purpose. To study the modern methodology for forming a list of mineragenic factors and prospecting signs of ore fields and deposits of copper-porphyry type based on reference objects and model constructions on the example of deposits of JungarBalkhash folded region. Methodology. The methodology for identifying the desired factors and criteria is based on the collection and analysis of published and historical data, formation of digital databases using raster and vector geological maps. It also includes the use of modern, advanced specialized technologies and software packages for geophysical surveys and remote sensing data. According to the adopted technology, the results of aerospace methods are used, which include aerial photography, space radar imaging, infrared and spectrozonal surveys and others. The research involves interpretation of WorldView-3 satellite images. Findings. A list of metallogenic characteristics describing potential copper-porphyry mineralization within the study area has been compiled. Using the Spectral Evolution PSM-3500 infrared spectrometer, characteristic areas of secondary changes in copper-porphyry systems have been identified. ASTER spectral satellite radiometer data have identified mineral spectra, iron hydroxides, propylitic associations, areas of quartzite formation and silicification. By interpreting WorldView-3 satellite images, digital files have been obtained identifying iron ore minerals (hematite, goethite), secondary quartzites (advanced argillizites), varieties of sericite and other clay minerals, silicon, carbonates and propylites (chlorite, epidote). Based on interpretation, “parquet” fracturing in granite bodies and in the area of volcanogenic and sedimentary strata development has been identified, as well as structural lines indicating the strike of rock layers. Originality. Using the example of an exploration area based on the analysis of a priori and up-to-date data, the nature of a set of relevant criteria and signs for predicting and prospecting has been determined, aimed at increasing the reliability and accuracy of formation of geological-geophysical models. Practical value. The collected and systematized geophysical data can serve as a basis for developing plans for further geological exploration, identifying promising areas, determining the required volumes and methods of geophysical surveys. They can also contribute to the increase in estimate of reserves and production at mining sites. The prepared models are intended for preliminary assessment of known and newly discovered ore deposits of various types, as well as for determining the directions of geological exploration in the areas of prospecting the Northern Pribalkhash. [ABSTRACT FROM AUTHOR]

It is critical to characterize submarine landslide hazards near dense coastal populations, especially in areas with active faults, which can trigger slope failure, subsequent tsunamis, and damage seabed infrastructure during earthquake shaking. Offshore southern California, numerous marine geophysical surveys have been conducted over the past decade, and high‐resolution bathymetric and subsurface data now cover about 60 percent of the total region between Point Conception and the United States‐Mexico border from the California coast out to the base of Patton Escarpment ∼200 km offshore. In a comprehensive compilation and interpretive mapping effort, we find evidence of seafloor failure throughout offshore southern California with nearly 1,500 submarine landslide‐related features, including 63 discrete slide deposits with debris and >1,400 slide‐related scarps. In our analysis, we highlight new mapping of submarine landslides in Catalina Basin, the Del Mar slide, the San Gabriel slide complex, and the 232 km2 San Nicolas slide, the largest area of any known submarine landslide mass offshore southern California. Analysis of the spatial distribution of submarine landslide features suggests that most mapped slide features are located relatively near coastal sediment sources, particularly during sea‐level lowstand conditions, which underscores the importance of sediment supply and sediment accumulation on low‐gradient slopes as failure preconditioning processes. Tectonically driven uplift at shelf edges and along basin flanks is another key preconditioning factor, and our results also suggest that earthquakes along active faults trigger mass wasting, especially for repeated, small‐scale failures on tectonically steepened slopes. Plain Language Summary: Submarine landslides can damage seabed infrastructure such as cables and moorings, cause tsunamis, and be triggered by shaking from earthquakes. It is important to understand the risk of submarine landslides near dense coastal populations, particularly where earthquakes also pose hazards. Offshore southern California, we have new high‐resolution seafloor and subsurface imaging data that help us to identify submarine landslide deposits in the marine environment. In our study, we map and compile evidence for submarine landslides and find nearly 1,500 slide‐related features, 63 of which feature significant debris deposits. We describe some of the larger slides in this study for the first time, including submarine landslides in Catalina Basin, the Del Mar slide, the San Gabriel slide complex, and the 232 square kilometer San Nicolas slide, which is one of the largest known submarine landslide masses offshore southern California. Our work suggests that submarine landslide failure processes offshore southern California require a combination of (a) significant sediment supply, which is enhanced during low sea‐level conditions, (b) uplift and steepening along faults, and (c) earthquake shaking to trigger slide events. Key Points: Comprehensive analysis of submarine landslides in southern California provides new metrics on their size, distribution, timing, and geologySubmarine landslide failure processes are controlled by a combination of sediment deposition, tectonic uplift, and earthquake triggeringSmall‐scale failures dominate steep areas near Quaternary faults; large slides tend to occur on lower slopes farther from faults [ABSTRACT FROM AUTHOR]

Geothermal resources, as abundant renewable and clean natural resources on Earth, have been utilized for geothermal power generation in 29 countries. Guangdong Province, as one of the most developed, economically vibrant, and attractive investment regions in China, has experienced rapid economic growth. However, further development is constrained by resource limitations and severe ecological environmental pressures. The issue of energy consumption and economic growth imbalance needs to be urgently addressed. Geothermal energy, as a clean and stable form of energy, can reduce reliance on fossil fuels, decrease dependence on imported energy, and enhance national energy security. In this study, geological survey, geophysical survey, geochemical survey, remote sensing detection and drilling were carried out in the Shiba–Huangshadong area of Huizhou, and by analyzing the data on geothermal energy reserves in the study area, the available geothermal energy and its potentials in the study area were identified and its impact on the current energy consumption in Huizhou City was assessed, to validate the feasibility of the detailed application of the geothermal energy in the Greater Bay Area, which will enable the energy structure of Huizhou City optimize the energy structure. [ABSTRACT FROM AUTHOR]

As a result of a deep burial depth (> 6.5 km), the depositional history of the Early to Middle Ordovician carbonate platform in the Shuntuoguole Low Uplift (Tarim Basin, NW China) has been difficult to unravel, leading to problems in understanding the controls of the facies distribution, particularly in terms of petroleum exploration. Integrated with geophysical surveys, detailed sedimentological observations document the platform evolution and show that a carbonate ramp system developed in the Shuntuoguole Low Uplift during the Early-Middle Ordovician, with twelve lithofacies types arranged into two facies associations, including peritidal to semi-restricted subtidal and open-marine subtidal facies. Based on the tempo-spatial distribution of lithofacies, seven third-order depositional sequences are identified, each composed of a transgressive lower package and a regressive upper part. Their sequence boundaries are commonly characterised by a transitional zone with no obvious subaerial exposure features. The correlation of relative sea-level (or accommodation space) changes derived from the vertical stacking pattern of facies with the global sea-level curve of Haq and Schutter (2008) and sea-level oscillations of coeval successions worldwide suggests that eustatic sea-level fluctuations were the overriding factor controlling the development and evolution of this carbonate ramp during the Early-Middle Ordovician. Meanwhile, regional or local tectonic subsidence and environmental factors (e.g. palaeoclimate and prevailing wind) also exerted an influence on the depositional processes of the Shuntuoguole Low Uplift over this time interval. [ABSTRACT FROM AUTHOR]

Tectonic deformation within fault damage zones can influence slope stability and landslide failure mechanisms due to rock mass strength effects and the presence of tectonic structures. Here, we used detailed site investigations to evaluate controls on deformation within the Half Moon Bay landslide complex, located ~1 km from the surface trace of the Hope fault in the South Island of New Zealand. During the 2016 Mw 7.8 Kaikōura earthquake, the slope experienced up to ~13 m of displacement and partially transitioned into a rock avalanche (with a volume of ~350,000 m³). Deep-seated deformation of the entire slope predated the 2016 earthquake. Results of geomorphological analysis, field mapping, geophysical surveys, slope displacement, and a 60-mdeep borehole in the incipient portion of the landslide indicated the presence of a subvertical tectonic fabric and intense fracturing and weathering of the rock mass, which gradually decrease with depth. Based on these results, we established a conceptual model wherein the landslide failure mechanism is a combination of flexural toppling along the subvertical structures coupled with joint-step-path sliding along preexisting, closely spaced discontinuities within the graywacke rock mass. Coseismic slope displacements revealed a large area of incipient failure behind the headscarp of the 2016 rock avalanche, which will likely result in further avalanching at the site. This case study demonstrates that inherited tectonic structures (combined with seismicity and weathering in an oversteepened coastal slope) play an important role in the evolution of hillslopes near active faults. [ABSTRACT FROM AUTHOR]

For the eastern zone of the North Caucasus, including the Terek–Caspian trough, Dagestan wedge, and adjacent structures, with the maximum coverage of the data from the Federal network of seismological observations of the Geophysical Survey of the Russian Academy of Sciences (GS RAS), the regional frequency-dependent relations are determined using the Coda Wave Decay (CWD) method to estimate the seismic Q-factor of the Earth's crust and upper mantle. In total, waveforms from 394 crustal earthquakes with source depths from 1 to 42 km and magnitudes М from 2.2 to 5.5 are analyzed using the Coda Q module of the SEISAN software package (Havskov et al., 2020). The seismic Q estimation technique using the single-scattering model is described in detail. Recommendations are given how to practically use the obtained estimates characterizing the wave properties of different-scale volumes of the fault-block geological environment to make attenuation corrections when calculating the source spectral parameters in the eastern zone of the North Caucasus. The results of the study will help to augment the information content of earthquake catalogs, in particular, with the data on energy characteristics of seismic events (universal moment magnitude values Mw) in the most seismically active regions of the Russian Federation. [ABSTRACT FROM AUTHOR]

Coral reef islands are biodiversity hotspots with high conservation value, but we have a poor understanding of how island vegetation, through transpiration, influences groundwater nutrient supply to adjacent reef systems. Here we combine stable isotope tracing, geophysical surveys, and satellite analysis to unravel the links between transpiration and the discharge of groundwater nitrate to the waters surrounding a coral reef island (Lady Elliot Island in the Great Barrier Reef). Over a 2‐year study period (2020–2021) there was a net loss of freshwater from the island, that is, evapotranspiration (ET) exceeded rainfall, largely caused by high rates of transpiration (73% of ET). Transpiration was higher in forested areas, and groundwater salinity appeared to be higher there. By tracing the nitrogen stable isotope signature of groundwater nitrate into reef organism tissue we were able to map groundwater nitrogen discharge spatially and temporally. Groundwater nitrogen discharge was focussed on one side of the island and did not vary seasonally as expected, despite reduced rainfall and seabird guano inputs over the austral winter/spring. Based on our results, we propose that transpiration by island vegetation slows groundwater flow and concentrates nitrate in the groundwater being released to the surrounding reef system. High concentrations of nitrate in groundwater (up to 27 mmol L−) were observed on Lady Elliot Island and these seem to have increased since 2014, but further work is required to understand if this is a normal scenario for tropical coral islands or the result of the islands' revegetation program. Plain Language Summary: Coral reef islands are biodiversity hotspots that are considered to be biological refuges against climate change. As such there is a concerted effort to fully understand and adaptively manage these ecosystems. However, we lack fundamental information on how the presence of vegetation, and specifically transpiration, influences the nutrient biogeochemistry of tropical islands. This is important as coral reefs are considered to be susceptible to nutrient availability. Here we combine a range of biogeochemical techniques to unravel the links between transpiration and the discharge of groundwater nitrogen to the waters surrounding a coral reef island (Lady Elliot Island in the Great Barrier Reef). We find that high rates of transpiration across seasons alters the nutrient dynamics of the aquifer. In particular we propose that transpiration slows groundwater flow and concentrates nitrate in groundwater being released to surrounding reefs. It is not clear whether this process is part of a natural cycle or if it is influenced by the active revegetation program on the island. Future work should try to address this knowledge gap as this has important implications for the continued management of these critical ecosystems. Key Points: Transpiration by island vegetation appears to slow groundwater flow and concentrate nitrate in groundwaterIt is not clear whether transpiration drives long term increases in groundwater nitrate concentrations or discharge to the local reefThe relationships between revegetation, transpiration, and groundwater nitrogen dynamics need to be addressed further [ABSTRACT FROM AUTHOR]

Peatlands, as an important carbon sink, store a large amount of atmospheric carbon that is vulnerable to becoming a carbon emission source due to the disturbance of the peat layer by natural and anthropogenic processes. The Kuan Kreng peat swamp forest is the second largest peatland in Thailand and is in coastal wetland serving for carbon stock in the subsurface. To assess carbon stock in peatland, the thickness and distribution of the peat layer are necessary. This study determines physical and chemical characteristics of the peatlands in the coastal wetland, southern Thailand by conventional core study and geophysical surveys, including ground penetrating radar (GPR) and electrical resistivity imaging (ERI). There is a significant relationship between chemical and physical properties from the peat layer, which is useful to approximately predict the physical properties and peat layers in the geophysical profiles. The resistivity profiles exhibit high resistivity response, peat between 21.9 and 145.0 ohm-m, interpreted as the peat layers in the shallow subsurface. The high resolution GPR profiles provide an average GPR velocity in peat of 0.040 m/ns and a relative dielectric constant of 54.9 for the peat layers. The peat layer is characterized by a high amplitude of reflection in the GPR profiles. The thickness of the peat layers was estimated from the geophysical surveys and the drilling cores having an average thickness of 18 cm. Average values of bulk density (0.19 g/cm3) and TOC (31.18 wt. %) from the drilling core samples are used to calculate the carbon density in the peat layers giving a result of 59.24 Kg C/m3. Hence, the carbon stock at the Kuan Kreng peat swamp forest is estimated at least 7.53 megaton carbon, which is much higher than aboveground biomass carbon in this area. The innumerably high amount of carbon stock could raise awareness of peatland disturbances. [ABSTRACT FROM AUTHOR]

Retaining a waterproof coal pillar is an important measure to defend against water inrush accidents in mining areas and guarantee the safe mining of the next working face. In this paper, the mechanical model of the coal pillar is established and the calculation formula of the waterproof coal pillar width is derived. Then, the development of the water-conducting fracture zone of the overlying rock layer under different coal pillar widths is analyzed using numerical simulation and finally, the integrity of the coal pillar is detected using the geophysical survey method. The main conclusions are as follows: (1) According to the mechanical failure characteristics of the coal pillar, it can be divided into the plastic zone, elastic zone, and water pressure damage zone. The mechanical calculation model for each zone was established, and the formula for calculating the width of the waterproof coal pillar was obtained. (2) Numerical simulation was employed to investigate the development condition of the water conducting fracture zone in the overlying rock strata under the actual width of the waterproof coal pillar; the simulation results indicated that the water conducting fracture zone of two working faces was not connected, which can effectively prevent the accumulation of water in the 2303 goaf. (3) On-site geophysical surveys determined that the influence of water-logged goaf on the coal pillar is between 5 to 15 m; the integrity of the waterproof coal pillar is good, which effectively prevents water accumulation in the previous working face goaf and ensures safe mining in the next working face. [ABSTRACT FROM AUTHOR]

In the field of the restoration of monumental heritage, non-destructive geophysical techniques have gained an already widely acknowledged importance. The possibility to understand the state of preservation of the artefacts without resorting to a destructive action is extremely useful in identifying unknown or presumed emergencies in order to better lead the restoration operations. At present geophysics is underutilised and furthermore, common techniques may not be optimal for some specific targets or sites. Therefore, more controlled research is needed to better understand the applicability of these methodologies when searching for cultural heritage applications in various material types. The purpose of this paper is to provide a new approach that involves the joint use of several geophysical methods for the study of the probable causes of deterioration on a monument of considerable historical and artistic importance. The monument is the Basilica of Santa Croce in Lecce. It is a baroque church internationally well-known. The starting point of this research was the evidence that some structures of the façade are more damaged and present signs of subsidence. The study of the causes of damage was dealt with a geophysical survey using ground-penetrating radar and electrical resistivity tomography. The results demonstrate the effectiveness of the choice of the two methods and allow to obtain information on buried structures both inside the church and on the façade and to locate and identify anomalies related to a restoration intervention carried out in the 80s. Furthermore, a microclimatic analysis performed inside the Basilica shows a probable connection between the humidity present on the surface and the conductive layers present in the subsoil and highlighted with the electrical method. [ABSTRACT FROM AUTHOR]

To better understand the location and help in the conservation of buried structures in the ancient site of Tusculum, in Central Italy, archaeological and multi-methodological geophysical studies were developed in the recent last years. These studies included geophysical surveys, which were combined with topographical survey and direct archaeological excavations. Tusculum is one of the largest Roman archaeological sites in the Alban Hills, located in the Latium region (Italy), about 25 km South-East of Rome. This settlement was inhabited since pre-Roman times, up to the middle ages. The objective of the Tusculum Project is to verify the town-planning of Tusculum and to obtain information about the location, shape, depth and size of the hypothesised buried buildings. With these aims, multi-methodological geophysical surveys have been carried out in the time range 2016–2019 to locate the archaeological remains in different portions of the studied area and to verify the orientation of the underground aqueduct system. GPR and gradiometric surveys were carried out to investigate the archaeological remains, while ERT surveys, were employed to find evidence of undiscovered parts of the underground aqueduct system. These results, along with geological studies and historic evidence, are being examined by archaeologist to understand the limits of the town and how water was supplied to such a large, populated settlement. The obtained results show very good correspondence between the buried architecture, the geophysical anomalies and the archaeological excavations. A number of unexpected buried buildings were discovered, which were excavated in 2017 and 2018, which showed remains of buried public thermal bath and a large church with surrounding funerary area built in the Middle Ages. [ABSTRACT FROM AUTHOR]

Holleford Crater is a deeply buried, 2.35 km diameter late Proterozoic‐early Cambrian (550 ± 50 Ma) simple impact crater located in southeastern Ontario, Canada. Exploration drilling in the 1950–60s indicated a >450 m deep, simple impact structure with an infill stratigraphy of Cambro‐Ordovician clastic and carbonate sediments and a −2.2 mGal gravity anomaly. We conducted new ground‐based geophysical surveys (magnetics, gravity) and potential field modeling to better resolve the buried impact structure depth, subsurface geometry, and postimpact modification. Geophysical surveys reveal a well‐defined ~3 mGal Bouguer gravity low and <20 nT residual magnetic anomaly over the crater basin. The lack of a well‐defined magnetic anomaly is due to the low magnetic contrast between Mesoproterozoic metasedimentary target rocks and Paleozoic infill sediments. The modeled basement surface shows a deeply buried (>400 m), eroded simple impact structure with a rim‐to‐rim diameter (D) of 1.8–2 km, a residual rim height of about 30 m and a true depth (dt) >400 m. The modeled diameter is smaller than the previous estimate (2.35 km) based on the surface outcrop pattern of Paleozoic strata, which overestimates the buried impact structure dimensions. The modeled basement surface identifies a rim breach and a possible fluvial outflow channel in the southeast impact structure rim. The channel is up to 150 m deep and 400 m in width and has morphology similar to outlet channels produced by fluvial rim dissection of terrestrial impact structures and "tadpole craters" on Mars. [ABSTRACT FROM AUTHOR]

This publication details a hydrologically connected inundation modeling method developed by the Alaska Division of Geological & Geophysical Surveys (DGGS) using geographic information system (GIS) processing tools. This method improves upon a widely used, GIS-based inundation modeling method commonly called a bathtub model (BTM; Poulter and Halpin, 2008). DGGS's method considers hydrological barriers and connections during the modeling process to map the extent of inundation more accurately (fig. 1). Leveraging Esri's ArcGIS Pro Raster Function tools, DGGS takes advantage of in-memory processing to improve the speed and efficiency of our models. This method specifically models still water inundation at a community-specific level and is not comparable with coastal total water level models, nor is it appropriate for regional or larger areas. With the increasing prevalence of high-resolution digital elevation models (DEM), DGGS's still water inundation model (SWIM) method is an effective, locally replicable alternative to larger, more complex modeling methods, making our approach accessible to municipal and community analysts. [ABSTRACT FROM AUTHOR]

The geological map of the Klenov Pluton (Moldanubian Batholith), and its 3D visualization, brings the new findings in the context of granite emplacement within late-Variscan settings. The Klenov Pluton has a peraluminous composition resulting from partial melting of metasedimentary sources and subsequent differentiation. The new ages 327.14 ± 0.21 Ma and 327.80 ± 0.37 Ma, reflect the narrow time-span of magma emplacement and cooling. The 327 Ma Klenov Pluton was emplaced syntectonically as a 'sheet-like' granite intrusion at depth ca. 10 kilometers during the later stages of the Pelhřimov Core Complex exhumation (at ca. 329 to 327 Ma) associated with ~N--S oriented compression. Gravity modelling suggests that the Klenov Pluton has an asymmetric shape where its western flank is parallel to the ~NW moderately dipping Pelhřimov Core Complex. The eastern margin of the Pluton is shallower and has been later modified by ~SE-side-up normal faulting (Lodhéřov Fault Zone). [ABSTRACT FROM AUTHOR]

Connecting stakeholders in heritage, archaeology, and precision agriculture can help us to understand the impacts of and shape positive outcomes for this transformation by developing common ground and shared agendas. Technologies such as satellite imaging, drone-based imaging, and geophysical survey are used in the practice of precision agriculture to support farmers and land managers to make data-driven management decisions. Archaeologists use many of these same technologies to investigate the buried evidence for past human activities and make this evidence for the heritage of agricultural landscapes visible. Fundamentally, practitioners and researchers in both precision agriculture and archaeology are invested in developing a better understanding of soils, plants, topography, water, insects, current farming practices and anything else that shapes agricultural landscapes. Drone-based geophysical survey, still in development, has the potential to facilitate increased field access and improve survey timings, if the signal-to-noise ratio of the measurement is good and the depth of investigation sufficient. In agricultural geophysics, the relationship between measurements and the physical/chemical parameters of the soil under investigation needs to be identified and their spatial variation understood. [ABSTRACT FROM AUTHOR]

The Roman villa at Matrice, located in Molise, central Italy, offers a rare opportunity to reflect on a typology of site that is sparsely documented. The building at Matrice presents distinctive elements of a rural villa of the 1st century AD, dedicated to agricultural, pastoral and wine production activities. However, these elements are adapted here in a decentralized area of the Roman State, where the local elites did not exhibit the same opulence of those belonging to major urban centres. The villa displays peculiar aspects and reflects local economic, social, and geographical conditions. After the excavation of the 1980s, archaeological research at Matrice was renewed in 2017 by a joint team from the British School at Rome, King's College London, and the Ashmolean Museum of Oxford. The project used a preliminary geophysical survey to explore the area around the site, discovering new archaeological features. The following excavation season assessed the geophysical results and provided significant stratigraphic information. The paper focuses on the methodological aspect of the research, comparing the geophysical results with data from the excavation. It also underlines the potential implications of the new evidence for the understanding of the site. [ABSTRACT FROM AUTHOR]

Ground gravity and magnetic geophysical surveys are proven veritable tool in the imagery of the subsurface through the analyses of their responses (potential field data). This research attempts to delineate subsurface linear structures that are possible conduits for mineral accumulation at a 2,500 m² active exploration site of FUNAAB, Abeokuta region. Abeokuta is embayed in the Dahomey Basin comprising of magmatic older granites of Precambrian age to early Paleozoic age. The qualitative interpretation technique employed by visualizing the grids reveals variations in density contrasts and susceptibilities, which connote the lithological distribution of the basement. Areas of high gravity and magnetic values directly correspond to areas of high density bodies and magnetically susceptible mineral contents, respectively. While the lows and steep discontinuities of both gravity and magnetic maps predict possible entrapments of mineral accumulation in the study area. The depth evaluation techniques employed are Peter’s Half Slope Method (PHSM) and 3D Euler deconvolution, showing the magnetic depths to basement range as 3.18 m to 5.88 m for PHSM and 1.00 m to 4.43 m for 3D Euler deconvolution. The gravity depth to basement reveals 7.03 m to 14.72 m for PHSM and 0.96 m to 4.13 m for 3D Euler deconvolution. The average depth results obtained clearly show that the study location is composed of shallow depth intrusive sources. [ABSTRACT FROM AUTHOR]

The gravity and the magnetic data sets are utilized to model the Hematite ore body. The cross-gradient joint inversion is used to invert the data sets simultaneously. To discretize the model space, the advanced meshing algorithm (Octree mesh) has been applied. The sparse norm and cross-gradient inversion modules in Python, accessible through Simulation and Parameter Estimation in Geophysics (SimPEG, version 0.17.0) website, have been applied to the inversion process. The sparse norm inversions do not provide reasonable results, particularly for the gravity data set. The estimated density contrasts through the inversion process are very low and unrealistic and on the other hand, the north-south cross sections do not represent a real image from the subsurface sources. The magnetic modeling results obtained through sparse norm inversion also show unrealistic characters, particularly for the 3-dimensional figure of the subsurface anomaly. The cross-gradient inversion acts quite successfully for both gravity and magnetic models in spite of high noise level in gravity data and the weak signal of magnetic data. The results are in good agreement with geological evidences and also former geophysical survey in the survey area. The priority of cross-gradient inversion of gravity and magnetic data sets to separate inversion is quite clear, despite the weak magnetic signal. [ABSTRACT FROM AUTHOR]

Several Roman period surface scatters and a settlement located in the Yambol District, along the Tundzha River, have been investigated within the last few years. Surface surveys and geophysical prospection were combined with a thorough material evaluation, to allow a description of the possible dimensions and character of several sites, all likely located in the territory of ancient Kabyle. The investigation focused on several single features located in the Tundzha Municipality, such as the extensive settlement near Kozarevo village and a smaller installation, perhaps a villa, near the Roman settlement at Kabyle. Several scatters, already detected by the Tundzha Regional Archaeological Project, were re-surveyed in Elhovo Municipality, between the Dereorman and Gerenska rivers. The territory along the two rivers seems to have been densely populated during the 2nd-4th c. AD, with about 11 scatters dated to the Roman period, likely representing small rural settlements, distributed in regular intervals along the two rivers. One of the settlements on the Dereorman River, Yurta-Stroyno, surveyed and excavated in 2014-2016, provided a comparative base for the rest of the area. Evaluating the gathered data, the territory of Kabyle seems to have been quite self-sufficient during the Roman period. The rural settlements provide evidence of raw material processing, production of everyday items, as well as a preference for the locally available products, such as household pottery, limiting the number of pottery imports to a minimum. [ABSTRACT FROM AUTHOR]

To effectively delineate the spatial distribution of oil contaminant plumes, geophysical methods indirectly measure the physical properties of the subsurface and can provide spatial information and images on a large scale, as opposed to traditional direct methods such as borehole drilling, sampling, and chemical analysis, which are time-consuming and costly. However, interpreting geophysical responses over non-aqueous phase liquid (NAPL)–contaminated sites is not straightforward due to inconsistent responses from biodegraded oil contaminants. In this study, we performed multi-geophysical surveys including seismic refraction, ground-penetrating radar, electrical resistivity tomography (ERT), and induced polarization (IP) surveys, to locate NAPL-contaminated zones in a clay-rich site. To reduce ambiguity in discriminating between oil contaminants and clay layers, we first figure out the geological structure of the site by interpreting geophysical data incorporating with borehole data. The ERT data highlighted the heavily contaminated regions in the unsaturated zone but were less distinctive below groundwater levels. Conversely, IP responses revealed potential hotspots within the clay layers, extending beneath the groundwater. Considering the 3D geological model, NAPL-contaminated zones are properly delineated through interpretation of ERT and IP data together with borehole data, and the contaminant source zone was properly estimated within the site. [ABSTRACT FROM AUTHOR]

This paper explores the critical role of geotechnical aspects in optimizing the performance and resilience of wind turbine foundations. It emphasizes the importance of comprehensive geotechnical investigations, including soil borings, in-situ testing, geophysical surveys, and laboratory analysis, to inform foundation design parameters. Remote sensing techniques aid in optimizing turbine layout design, while the collaboration between geotechnical and structural engineers ensures effective foundation design. Ultimately, the comprehensive characterization of wind turbine sites is essential for ensuring stability, reliability, and long-term performance, contributing to the sustainable growth of renewable energy infrastructure. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologia Historica is the property of Masaryk University, Faculty of Arts 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.)

Copyright of Archaeologia Historica is the property of Masaryk University, Faculty of Arts 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.)

Copyright of Spal: Revista de Prehistoria y Arqueologia de la Universidad de Sevilla is the property of Spal. Revista de Prehistoria y Arqueologia de la Universidad de Sevilla 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.)

In the last decades, the concern for infrastructure damage and collapse due to natural hazards has globally increased. Highways, railways, bridges, and tunnels, worldwide, have faced consistent damage or destruction from landslides and floods, exacerbated by the ongoing climate change and population growth. In Italy, significant examples of these events are the recent failures of the Polcevera and Magra bridges, impacting people and the local economy. Especially, after the Polcevera bridge collapse, the Italian government has considered the need for specific practices of bridge/viaduct risk assessment. In response to this requirement, governmental agencies have developed specific projects oriented to the development of specific guidelines. This work is part of one of these projects, entrusted specifically to the ReLuis consortium, aimed at contributing to the application and optimization of an experimental protocol for bridge/viaduct classification in natural-hazard related risk assessment perspective. In this context, this work describes the results of an initial-level analysis of the interaction condition of a slowmoving landslide with the “Villa Ilii” Viaduct located along the A24 highway at Colledara, in the Teramo Province. The analysis aims to evaluate landslide characteristics, including landslide anatomy and kinematics, and their potential impact, contributing to define and identify viaduct classification in landslide risk perspective. The study area is characterized by the presence of the Laga Formation, mainly represented by sandstones and marls, overlaid by sandy Quaternary deposits. In fact the formation of the Laga (Ricci Lucchi, 1975) represents the filling of one of the many foreland basins currently exposed in a wide area between southern Marche and northern Abruzzo, developed at the forefront of the Apennines during its migration eastward and northeastward, as a result of the collision between the European lithospheric plate and the Adriatic plate, a likely protrusion of the African continent.), Methods including existing data collection, field surveys, numerical chartography analysis, geophysical surveys and PS InSAR technique were used to reconstruct the geological setting of the slope affected by the landslide, its anatomy and kinematics. Especially, multiple field surveys and numerical cartography analysis revealed landslide extent over a surface of 78,000 m², geophysical survey indicated a landslide thickness of around 15 m, comparable with the thickness of Quaternary deposits, and SAR-interferometric data, processed by SUBSIDENCE software, indicated persistent slow movement typically accelerating in spring. These data are crucial for understanding the landslide’s potential impact on the “Villa Ilii” viaduct’s structural conditions, already exhibiting local deformation and cracking, similar to surrounding settlements. [ABSTRACT FROM AUTHOR]

The document titled "Acknowledgement of Reviewers for 2023" expresses gratitude to the scientists and experts who reviewed papers for Surveys in Geophysics from January 2023 to December 2023. The Editor in Chief, Dr. Michael J. Rycroft, and the Publisher acknowledge the contributions of numerous colleagues from various fields. The document lists the names of these individuals, demonstrating the wide range of expertise involved in the review process. Springer Nature, the publisher, maintains a neutral stance regarding jurisdictional claims and institutional affiliations. [Extracted from the article]

The specificity of the behavior of the soil massif near the tunnel under construction in difficult mining conditions is considered. It was revealed through the joint interpretation of the results of geophysical measurements in the tunnel and computer simulation. The results of field geophysical studies to identify areas of decompacted soil behind the lining in two existing tunnels during successive drilling of two new tunnels under them are described. A method to analyze the response of the lining to impact was used providing for the calculation of its energy. It has been established that the decompaction zones are mainly located in the lateral lower areas of the tunnel. To substantiate the mechanism of formation of cavities, computer simulations were carried out using the finite element method with the COMSOL Multiphysics software. The finite element model is built on the Drucker – Prager criterion in the variant of a two-dimensional problem statement. It is shown that at the initial position of two old tunnels, the areas of decompaction can develop mainly on the sides. The position of the zones changes significantly when excavating two new tunnels. Soil decompaction zones appear between the tunnels and there is a tendency for the areas to spread to the upper point of the tunnel. According to geophysical data time delays in the impact of new tunnels on the existing line are noted, as well as a decrease in the size of decompacted soil areas over time. There is a satisfactory agreement between the positions of the decompaction areas and voids obtained by the geophysical method and the results of numerical simulation.

Evidence of precontact agricultural practices demonstrating how and where crops were grown is often scant because of poor preservation and modern land use practices. As a result, relatively few sites have been identified that document farm fields or garden beds. We document remnants of a ridge and furrow agricultural system found at Angel Mounds, an important regional Mississippian site, in Indiana, USA. Researchers have identified many different cultigens from Angel Mounds, but the location, type, and age of fields had not been identified previously. Our research team recovered data indicating that the third terrace of Angel Mounds supported ridge and furrow agriculture where villagers grew maize, beans, and gourds for several centuries. This study suggests that agricultural evidence is extant in buried contexts and that these features are easily overlooked using traditional geophysical and survey techniques. [ABSTRACT FROM AUTHOR]

This article includes a review of the structure and evolution of the Antarctic Earth crust (the Antarctic continent and the Southern Ocean) from the Archean to the Late Cenozoic, accompanied by the sketch of Antarctic tectonic provinces. It is based on the long-term research and preparation of the second edition of the Tectonic Map of the Antarctica at a scale of 1 : 10 000 000 with a detailed explanatory note in the International Commission for the Geological Map of the World. In the course of the work a large volume of geological and geophysical data of Russian Antarctic expeditions and expeditions of other countries were combined, analyzed, and interpreted, first of all, the data of geochemical and geochronological studies of rock specimens from outcropped regions and numerous geophysical surveys in the Southern Ocean. The structure and tectonic history of the Archean cratons and Proterozoic orogens of East Antarctica (with indication of the controversial issues of Precambrian evolution), the orogens of the Pacific margin, intraplate fold systems, continental margins, and the early sea floor spreading are considered. [ABSTRACT FROM AUTHOR]

Due to nonstandard anti-seepage facilities, aging failure, and other reasons, some tailings ponds have seepage problems. After analysis of the geological and hydrogeological conditions of a lead–zinc mine tailings pond, an interception, blocking, and drainage (IBD) system engineering scheme was used to comprehensively control the seepage problems there. In addition, we assessed the effectiveness of a grout curtain from the four dimensions of the point-line-surface-body (the 4D of PLSB), including a water pressure test (point), drilling and coring survey (line), geophysical test (surface), and a group-holes pumping test (body). The proposed method provides a comprehensive and accurate understanding of grouting efficiency assessment from the perspectives of permeability and tightness. [ABSTRACT FROM AUTHOR]

Fort Roberdeau was a lead mine in central Pennsylvania during the period of the American Revolution. Scant information exists on the original position of the fort, the location of mining activity in the area during the period of the Revolution, or artifacts from this period. Subsequent farming, mining exploration, and the placement of the current replica fort (erected 1976) obscure the landform and hinder identification of Revolutionary-period mining activities. As a means of locating where the mining activities occurred and the original position of the fort, this study integrates historical, geological, geophysical, geochemical, geomorphological, and archaeological data. Geological mapping identified potential areas of past mining, and geophysical resistivity surveys verified at least one Revolutionary-period mine, since the location and dimensions of the subsurface anomaly match historical records. The positions of period metallic artifacts in conjunction with a road and corner of the original fort (identified with LiDAR and thermal imagery) place the original fort near the current replica. [ABSTRACT FROM AUTHOR]

The Trans-Baikal parametric borehole drilled out a metamorphic core complex in the reference geological and geophysical profile within the Central Asian fold belt, south of the Mongol–Okhotsk suture zone. In the section of the borehole drilled to a depth of 2600 m, a set of geophysical, geological, and laboratory–analytical studies made it possible to identify three main structural elements of metamorphic core complexes: the upper plate, detachment, and the lower plate. The upper plate (slightly metamorphosed rocks) is represented by a serpentinite mélange separated from the underlying rocks of the lower plate by a zone of chlorite breccias (detachment). The lower plate as a part of the crystalline basement complex comprises rocks of granite–schist and granite–plagiogneiss subcomplexes. The granite–schist subcomplex is composed of mafic and intermediate schist with amphibolites and quartzites. Biotite granite is widespread in the section as layered veins with synkinematic signs. According to the preliminary estimates, the age of biotite granite is about 130 Ma. Schist is characterized by a mylonite structure at intervals of interbedding with biotite granite veins. In accordance with the geophysical survey data on the borehole and the petrophysical characteristics of cored rocks, the mylonite zone is the provenance of a series of inclined reflectors in the seismic RSS–CDP section, which can be traced to a depth of at least 10 km. The granite–plagiogneiss subcomplex is represented by plagiogneiss, leucogranite, and gneissic granite. In the Trans-Baikal parametric borehole, a detailed section of the Borshchovochnyi metamorphic core complex, fully characterized by core samples, was obtained. It should be considered as a reference for studying these structures. The investigation of this section will make it possible later to answer many questions about the formation and evolution of the Central Asian fold belt. [ABSTRACT FROM AUTHOR]

This paper reports results from an analysis of swarm seismic events that were recorded in 2018 in the area of the Elbrus Volcanic Center (EVC) by the North Caucasus Seismological Network of the Federal Research Center, Geophysical Survey, Russian Academy of Sciences (FRC GS RAS). The standard location procedure was used to find the hypocenters of recorded events in the EVC area. In the LOS program package, a complex combined location algorithm, methods for minimizing the time residuals at the source, and search over a grid with several trial depth values, were used to relocate the hypocenters of seismic events in swarm sequences. This approach enhances location reliability due to incorporation of the uncertainties related to erroneous onset identification and insignificant deviations of travel times that depend on the earth velocity model used here. A study of earthquake mechanisms for the larger earthquakes has determined the type of slip in agreement with the kinematics in the Elbrus–Mineralnye Vody normal-oblique fault zone. Correlation analysis of waveforms on the vertical component that have been filtered in the frequency range 1‒10 Hz, which includes P and S waves, at the nearest station shows a high agreement among the data under analysis (the correlation coefficient is R ≥ 0.85), thus indicating a high probability of all events having similar sources and propagation paths of seismic waves. Comparison of power spectral densities for individual earthquakes in the swarm sequences also demonstrates a high similarity. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings of the Prehistoric Society is the property of Cambridge University Press 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.)