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Tunnel resistivity deep learning inversion method based on physics‐driven and signal interpretability Near Surf. Geophys. (IF 1.6) Pub Date : 2024-03-09 Benchao Liu, Yuting Tang, Yongheng Zhang, Peng Jiang, Fengkai Zhang
Data‐driven deep learning technology has a strong non‐linear mapping ability and has good development potential in geophysical inversion problems. Traditional inversion techniques offer broad generality, but they can remain trapped in local minima, particularly for three‐dimensional tunnelling resistivity inversion. In this work, we present an inversion methodology that combines traditional physics‐driven
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Studying GPR's direct and reflected waves Near Surf. Geophys. (IF 1.6) Pub Date : 2024-03-08 Eleni Tokmaktsi, Nectaria Diamanti, Georgios Vargemezis, Antonios Giannopoulos, A. Peter Annan
As the transmitter and receiver (Tx and Rx, respectively) are located in close proximity during a typical ground‐penetrating radar (GPR) survey, the powerful signal generated by the Tx and which is then recorded by the Rx at various time delays, can be saturated at early times (i.e., this is the direct wave (DW) signal reaching the Rx). This often causes the masking of shallow targets, complicating
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Efficient and high‐resolution surface‐wave dispersive energy imaging using a proposed spatial smoothing propagation method Near Surf. Geophys. (IF 1.6) Pub Date : 2024-03-04 Tao He, Suping Peng, Henggao Geng
Surface‐wave information from seismic data can be used for near‐surface analysis, static computation and noise suppression. The multichannel analysis of surface waves method is a useful approach for obtaining the shear wave velocity of the near surface; however, rapidly generating an image of dispersive energy in the presence of coherent noise is a challenge. In this study, we propose the imaging of
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ERT data assimilation to characterize aquifer hydraulic conductivity heterogeneity through a heat-tracing experiment Near Surf. Geophys. (IF 1.6) Pub Date : 2023-12-22 Benyamin Shariatinik, Erwan Gloaguen, Jasmin Raymond, Louis-Charles Boutin, Gabriel Fabien-Ouellet
Geothermal energy systems, such as heat pumps relying on aquifers, use renewable sources of energy that are accessible in urban areas. It is necessary to characterize the subsurface hydraulic properties prior to the installation of such systems. In this context, a heat-tracing experiment is a typical field test that can help with the characterization of the subsurface. During a heat-tracing experiment
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Investigating soil layers with ground penetrating radar in the modern Yellow River Delta of China Near Surf. Geophys. (IF 1.6) Pub Date : 2023-12-16 Ping Wang, Xinju Li, Xiangyu Min, Shuo Xu, Guangming Zhao, Deqiang Fan
Soil layers affect the vertical movement of moisture and salt, eventually resulting in land cover and land use pattern changes. This study explored the ability of ground penetrating radar (GPR) to detect soil layers in the modern Yellow River Delta of China and assessed its accuracy. It was found that soil moisture and salt had a strong dampening effect on the electromagnetic wave signal which resulted
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Modelling and inferring fracture curvature from borehole GPR data: A case study from the Bedretto Laboratory, Switzerland Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-27 Daniel Escallon, Alexis Shakas, Hansruedi Maurer
Fracture curvature has been observed from the millimetre to the kilometre scales. Nevertheless, characterizing curvature remains challenging due to data sparsity and geometric ambiguities. As a result, most numerical models often assume planar fractures to ease computations. To address this limitation, we present a novel approach for inferring fracture geometry from travel-time data of electromagnetic
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Prediction of S-wave velocity models from surface waves using deep learning Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-21 Sangin Cho, Sukjoon Pyun, Byunghoon Choi, Ganghoon Lee, Seonghyung Jang, Yunseok Choi
Surface wave (SW) methods extract dispersion properties of wavefields propagating through a seismic array (1D or 2D). This is achieved by analysing the phase velocity versus frequency (or wavelength) data. Afterwards, an inversion process is performed to construct near-surface S-wave velocity models. Among the SW methods, multichannel analysis of SWs (MASW) is commonly used for engineering applications
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High-frequency wide-angle reflection and refraction method for structural engineering ground-penetrating radar surveys Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-20 Davide Campo
Electromagnetic wave velocity in ground-penetrating radar (GPR) constant offset data can be estimated via the diffraction hyperbola fitting method. This method is applicable when radargrams contain diffraction events (hyperbolic patterns) caused by scatters in the host smaller or equal to the dominant wavelength. An alternative method for velocity estimation, if no intrusive information is available
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Electrical resistivity tomography through reinforced concrete floor Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-20 Lichun Yang, Dikun Yang, Quan Yuan
The electrical resistivity tomography (ERT) method is often challenged by the presence of reinforced concrete (RC) in urban and industrial environments, because the embedded metallic wire mesh can severely distort the distribution of subsurface currents. We investigate one typical scenario in real applications, in which an RC floor overlays the natural topsoil or rock. Our synthetic forward simulations
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Assessing the dam's stability of the pond at the ‘El Bosque’ renaissance garden (Béjar, Spain) Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-16 Puy Ayarza, Mariano Yenes, Yolanda Sánchez-Sánchez, Imma Palomeras, José R. Martínez Catalán, Enrique Gil-Arranz, Juan Gómez Barreiro
The renaissance botanical garden of ‘El Bosque’ in Béjar (Salamanca, Spain) presents a pond bounded by a dam in its western part. The latter is formed by two masonry walls interconnected by buttresses. Cubic spaces in between are filled with a variable grain-size material (silty sand) that allows limited water flow. In recent years, the southern part of the dam has experienced localized and random
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Realistic simulation of GPR for landmine and IED detection including antenna models, soil dispersion and heterogeneity Near Surf. Geophys. (IF 1.6) Pub Date : 2023-11-06 Sam Stadler, Stephan Schennen, Thomas Hiller, Jan Igel
Ground-penetrating radar is an effective tool for detecting landmines and improvised explosive devices, but its performance is strongly influenced by subsurface properties as well as the characteristics of the target. To complement or replace labour-intensive experiments on test sites, cost-efficient electromagnetic wave propagation simulations using the finite-difference time-domain method are being
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A framework for GPR-based water leakage detection by integrating hydromechanical modelling into electromagnetic modelling Near Surf. Geophys. (IF 1.6) Pub Date : 2023-10-31 Huamei Zhu, Feng Xiao, Yimin Zhou, Wallace Wai Lok Lai, Qianbing Zhang
Timely and accurate detection of water pipe leakage is critical to preventing the loss of freshwater and predicting potential hazards induced by the change in underground water conditions, thereby developing mitigation strategies to improve the resilience of pipeline infrastructure. Ground-penetrating radar (GPR) has been widely applied to investigating ground conditions and detecting pipe leakage
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GPR velocity correction method in transversely heterogeneous media based on CMP data Near Surf. Geophys. (IF 1.6) Pub Date : 2023-10-29 Jianyu Ling, Rongyi Qian, Jun Zhang, Zhenning Ma, Xu Liu
Determining ground-penetrating radar (GPR) velocity has always been a critical problem. The GPR velocity estimation method based on common midpoint (CMP) data has been widely used because of its simplicity. However, we found that in sediment investigation and soil assessment, transversal heterogeneity is universal, which violates the basic assumption of velocity estimation through CMP data. Due to
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Developing a realistic numerical equivalent of a GPR antenna transducer using global optimizers Near Surf. Geophys. (IF 1.6) Pub Date : 2023-10-25 Ourania Patsia, Antonios Giannopoulos, Iraklis Giannakis
Numerical modelling of a ground-penetrating radar (GPR) has been widely used for predicting and assessing its performance. As the transmitter and the receiver are the most essential components of a GPR system, an accurate representation of them should be included in a model. Simulating a real system is particularly challenging, especially when it comes to commercial GPR systems. A three-dimensional
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Noise reduction algorithm of GPR data based on MMSE-PDS Near Surf. Geophys. (IF 1.6) Pub Date : 2023-10-16 Dejun Ma, Meng Fan, Di Zhang, Baode Fan
Ground-penetrating radar (GPR) technology is widely used in tunnel engineering detection; however, various factors, such as environmental interference and low signal-to-noise ratio characteristics of the echo data, limit the detection accuracy. A noise and interference suppression algorithm based on improved singular value decomposition is proposed in this paper. Compared with traditional filtering
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Computation of spectral parameters from time-domain induced polarization data for mineral identification Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-27 Indresh Kumar, V. Ramesh Babu, B. V. L. Kumar, J. K. Dash, A. K. Chaturvedi
Induced polarization (IP) effect is widely used in the search of disseminated minerals all over the world. Spectral parameters computed from time-domain IP data play a significant role in characterizing the sources, but mineral identification still remains a challenge. In this paper, the Levenberg–Marquardt method of inversion is adopted in estimating the spectral parameters from time-domain IP data
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The utilization of ghost reflections retrieved by seismic interferometry for layer-specific characterization of the shallow subsurface Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-26 Faezeh Shirmohammadi, Deyan Draganov, Ranajit Ghose
Seismic interferometry (SI) retrieves the Green function between two receiver locations using their recordings from a boundary of sources. When using sources and receivers only at the surface, the virtual-source gathers retrieved by SI contain pseudo-physical reflections as well as ghost (non-physical) reflections. These ghost reflections are the results of the cross-correlation or auto-correlation
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GPR modelling and inversion to quantify the debris content within ice Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-26 Ilaria Santin, Giacomo Roncoroni, Emanuele Forte, Pietro Gutgesell, Michele Pipan
Scattering is often detected when ground-penetrating radar (GPR) surveys are performed on glaciers at different latitudes and in various environments. This event is often seen as an undesirable feature on data, but it can be exploited to quantify the debris content in mountain glaciers through a dedicated scattering inversion approach. At first, we considered the possible variables affecting the scattering
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Synthetic modelling of railway trackbed for improved understanding of ground penetrating radar responses due to varying conditions Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-22 Matthew John Couchman, Brian Barrett, Asger Eriksen
Ground penetrating radar (GPR) is a commonly used tool for railway trackbed inspection due to its ability to collect information about subsurface materials at high resolution and high speed. Although GPR recording systems allow for the collection of vast quantities of data (hundreds of kilometres per day), accurate ground truth information is difficult to obtain. Models of trackbed can be used to generate
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Adding realistic noise models to synthetic ground-penetrating radar data Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-20 Sophie Marie Stephan, Niklas Allroggen, Jens Tronicke
Cost-effective computing capabilities have paved the road for the use of numerical modelling to develop advanced methods and applications of ground-penetrating radar (GPR). Realistic synthetic data and the corresponding modelling techniques, respectively, should consider all subsurface and above-ground aspects that influence GPR wave propagation and the characteristics of recorded signals. Critical
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Phase-shift correction of seismic reflections by means of spectral recomposition Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-15 Nelson Ricardo Coelho Flores Zuniga, Deyan Draganov, Ranajit Ghose
Using post-critical reflection data, it is possible to obtain useful information that allows more reliable geological characterization of the subsurface. However, the strong distortion caused by the phase shift in post-critical wavelets makes the use of post-critical reflections rather challenging. For this reason, an approach which is capable of estimating the phase shift of each wavelet of a reflection
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Integration of in-mine seismic and GPR surveys to gain advanced knowledge of Bushveld Complex orebodies Near Surf. Geophys. (IF 1.6) Pub Date : 2023-09-08 Emmanuel O. Onyebueke, Musa S. D. Manzi, Moyagabo K. Rapetsoa, Thabang Kgarume, Michael Westgate, Raymond J. Durrheim, Michelle Pienaar, Mpofana Sihoyiya, Mvikeli Mpofu, Michael Van Schoor, Phumlani Kubeka
Improving the exploration of deep-seated mineral deposits and assessing the stability of the mine pillars require that geophysical techniques are deployed in a fast and cost-effective manner with minimal environmental impact. This research presents results from in-mine reflection seismic experiments and a ground penetrating radar (GPR) survey conducted at the Maseve platinum mine, South Africa. The
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High-resolution P- and S-wavefield seismic investigations of a quick-clay site in southwest of Sweden Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-31 Papadopoulou Myrto, Malehmir Alireza, Markovic Magdalena, Berglund Johan
Seismic investigations were performed at a site in the southwest of Sweden where major quick-clay landslides have occurred in the past. Given the potential high risk of the area and the presence of medium infrastructures, the site posed a need for detailed investigations in a wide depth range and in high resolution. A high-fold seismic survey was designed and conducted along two profiles using a 1–2 m
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Hydrogeological structure of a granitic mountain catchment inferred from multi-method electrical resistivity datasets Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-30 Myriam Lajaunie, Julien Gance, Pascal Sailhac, Jean-Philippe Malet, Sheldon Warden, Hugo Larnier
Altered crystalline catchments are complex to study and model, as they present multi-scale properties that control their hydrogeological behaviour and that are difficult to capture through a single geophysical imaging technique. Several volumes of interest must be sampled in order that both small-scale (porosity, layering) and large-scale (bedrock, weathering, faults) heterogeneities can be captured
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Geophysical surveys and satellite imaging for the evaluation of near-surface terrain dynamic – A case study on Grand Portage, MN, USA Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-14 Jeongki Lee, Dante Fratta
Flooding, erosion and increases in the water level in Lake Superior have contributed to changes in the stem location and width of the Grand Portage Creek. Those events threaten parts of the Grand Portage National Monument, a historically significant site on the North Shore of Lake Superior, Minnesota. We performed geophysical surveys to investigate these dynamic effects. We studied the near-surface
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Numerical Fréchet derivatives of the displacement tensor for 2.5-D frequency-domain seismic full-waveform inversion in viscoelastic TTI media Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-10 Qingjie Yang, Bing Zhou, Marcus Engsig, Moosoo Won, Mohamed Kamel Riahi, Mohammad Al-khaleel, Stewart Greenhalgh
Derivatives of the displacement tensor with respect to the independent model parameters of the subsurface, also called Fréchet derivatives (or sensitivity kernels), are a key ingredient for seismic full-waveform inversion (FWI) with a local-search optimization algorithm. They provide a quantitative measure of the expected changes in the seismograms due to perturbations of the subsurface model parameters
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Case study of combined marine- and land-based passive seismic surveying in front of Nordenskiöldbreen outlet glacier, Adolfbukta, Svalbard Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-07 Helene Meling Stemland, Bent Ole Ruud, Tor Arne Johansen
Glaciers generate seismic waves due to calving and fracturing, meaning that recording and following event classification can be used to monitor glacier dynamics. Our aim with this study is to analyse seismic data acquired at the seabed and on land in front of Nordenskiöldbreen on Svalbard during 8 days in October 2020. The survey included 27 ocean bottom nodes, each equipped with 3 geophones and a
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Relating GPR system parameters to regulatory emissions limits Near Surf. Geophys. (IF 1.6) Pub Date : 2023-08-04 A. Peter Annan, Nectaria Diamanti, J. David Redman
Ground penetrating radar (GPR) is regulated regarding emission limits for ultra-wideband in a number of jurisdictions. The definitions of these regulations employ concepts and terminology that are more suited to traditional narrow band radio transmitters. Further, the emissions limits were based on limited quantitative factual information and have resulted in stringent limitations on GPR technology
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Reverse time migration imaging method for tunnel seismic forward-prospecting in viscoacoustic media Near Surf. Geophys. (IF 1.6) Pub Date : 2023-07-01 Yuxiao Ren, Xiangnan Ding, Meiyan Guo, Jiansen Wang, Xinji Xu
The imaging of geological structure in front of a tunnel face is conducive to the safe construction of tunnels. The reverse time migration (RTM) method is popular for its high imaging accuracy. However, most of the current tunnel seismic RTM methods assume complete elasticity, ignoring the nature of wave propagation attenuation, resulting in a poor imaging outcome, especially when tunnelling in the
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Evaluating the impact of correlated noise for time-lapse transient electromagnetic (TEM) monitoring studies Near Surf. Geophys. (IF 1.6) Pub Date : 2023-06-13 Paul McLachlan, Niels Bøie Christiensen, Denys Grombacher, Anders Vest Christiansen
Typically, transient electromagnetic (TEM) hydrogeological applications focus on spatial characterization. However, there is scope for utilizing time-lapse TEM to monitor dynamic processes. Changes related to hydrogeological processes are subtle; consequently, measurements must be of exceptional quality, and the presence and influence of noise sources must be well understood. A potentially problematic
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A joint geophysical approach to tune an integrated sinkhole monitoring method in evaporitic environments Near Surf. Geophys. (IF 1.6) Pub Date : 2023-06-03 Chiara Calligaris, Emanuele Forte, Alice Busetti, Luca Zini
Several methodologies allow for the detection and mapping of existing sinkholes in order to asses and manage the associated hazards and risks. These phenomena, linked to the presence of soluble rocks, are well known globally as they can cause severe damage to man-made structures. In this paper, we propose an integrated method applied to a test-site area in NE Italy where, on May 11 2017, a failure
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Soil resistivity measurements to evaluate subsoil salinity in rice production systems in the Vietnam Mekong Delta Near Surf. Geophys. (IF 1.6) Pub Date : 2023-05-31 Van Hong Nguyen, Jörn Germer, Van Nha Duong, Folkard Asch
Rice is a staple crop in the Vietnam Mekong Delta (VMD) in which more than half of Vietnam's rice is produced. However, rice production in the VMD is threatened by increasing saltwater intrusion due to land subsidence and climate change induced sea level rise. Saltwater intrusion into lowland areas through the canal system or capillary rise of saline water from near surface saline water tables may
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Resistivity and full-decay IP inversion for imaging a coastal aquifer prone to saline intrusion: The Pontina Plain case study (Central Italy) Near Surf. Geophys. (IF 1.6) Pub Date : 2023-05-18 Giorgio De Donno, Michele Cercato
Many coastal areas are affected by groundwater salinization due to the unsustainable use of groundwater resources. For a cost-effective quantitative assessment of groundwater resources, electrical resistivity (ER) tomography is often used as a standalone geophysical technique. In this paper, we present an application of the integration of direct-current ER and full-decay-induced polarization (IP) method
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Stiffness evolution of jet grouting columns performed under port caissons using PS suspension logging Near Surf. Geophys. (IF 1.6) Pub Date : 2023-05-12 Ángel Tijera, Enrique Asanza, Rubén Galindo, Marcelo Burgos
Jet grouting is one of the ground improvement techniques that are currently more widely used for upgrading gravity quays, especially to increase their berth depth. Irregular columns are formed because of a rotating high-pressure injection of a cementitious fluid in the ground that mixes with the natural soil. Despite its popularity, there is hardly any field experimentation on the stiffness gain of
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Multidimensional interpretation of radiomagnetotellurics and controlled-source radiomagnetotellurics data: A validation study Near Surf. Geophys. (IF 1.6) Pub Date : 2023-05-04 Shiva Fadavi Asghari, Arseny Shlykov, Maria Smirnova, Alexander Saraev, Pritam Yogeshwar, Bülent Tezkan
Radiomagnetotellurics (RMT) is an electromagnetic method that uses signals from radio transmitters broadcasting in the 10 kHz to 1 MHz frequency range. Due to its limited frequency range, RMT is commonly used as a shallow-depth investigation tool. However, in remote areas, there is a lack of radio transmitters and only signals from very low frequency (VLF) antennas (10–30 kHz frequency range) can be
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Interpretation and modeling of aeromagnetic data from helicopter surveys of the Morobe goldfield, Papua New Guinea Near Surf. Geophys. (IF 1.6) Pub Date : 2023-04-06 Mitchell S. Craig, Shadrach Noku
We interpreted and modelled aeromagnetic data from helicopter surveys of the Morobe goldfield, Papua New Guinea, by comparing gridded magnetic data with mapped surface geology. In some cases, geologic units may be recognized and distinguished based on contrasts in magnetic intensity and texture, including the Morobe Granodiorite, Kaindi Metamorphics, Bulolo Volcanics, and Langimar Beds. Magnetic anomalies
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Delimitation of massive sulphide bodies – Mise-à-la-masse method associated with induced polarization (IP) – A case history from Brazil Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-28 José Domingos Faraco Gallas
This paper presents a successful application of the mise-à-la-masse (MALM) or applied potential method in association with induced polarization (IP). MALM is known, since 1920, to be able to delimit electrically conductive massive mineralization. The method is used at the point where a drill hole intercepts a massive, mineralized body, to estimate its extent and shape. It is thus used as a complementary
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Influence of input motion and surface layer properties on seismic site response: A stochastic simulation method–based MLR model Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-27 Özgür Yıldız
Seismic site response analyses are simulations in which the effects of geological conditions on seismic waves are examined. The uncertainties that make these analyses crucial are defined as the source of motion, the travel path of seismic waves, and geological conditions. In this study, a series of non-linear seismic response analyses were performed using data from site investigation studies. The results
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Deep learning inversion method of tunnel resistivity synthetic data based on modelling data Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-13 Benchao Liu, Qian Guo, Yuting Tang, Peng Jang
Different water-bearing geological structures in front of the tunnel face are the main cause of tunnel water inrush disasters, affecting tunnel constructionsafety. Due to the narrow tunnel space and the limited data that can be detected, the traditional linear inversion method for detecting them has multiple solutions. In this paper, we establish a database with complex models, including water-bearing
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An improved correlation stack method for near-surface seismic data Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-07 Xinglin Lu, Wei Wang, Xuquan Hu, Xian Liao, Zhixiong Fu, Chaopeng Luo, Zheng Xu, Zhihong Fu
The seismic reflection method is the primary tool to provide detailed information on the near-surface. This paper proposes a common receiver correlation stack method. A towed seismograph is used to perform the rapid acquisition with small geophone spacing and a high sample rate, while broadband (from 1 Hz to 1000 Hz) seismic data are collected. Results of modelled and measured data indicate that the
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3D joint interpretation of potential field, geology, and well data to evaluate a salt dome in the Qarah-Aghaje area, Zanjan, NW Iran Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-06 Hosseinali Ghari, Ramin Varfinezhad, Saeed Parnow
As geophysical parameters are not always functionally related, treating multiple geophysical data sets to have a realistic geological model is not straightforward. An effective strategy to derive a geological interpretation is a combination of several geophysical methods with geological and well observations, each with its advantages and limitations. Gravity and magnetic methods are encouraging tools
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Finetuning ground penetrating radar velocity analysis from hyperbola fitting using migration Near Surf. Geophys. (IF 1.6) Pub Date : 2023-03-04 Jan Steinar Rønning
The widely used tool, ground penetrating radar (GPR), has proven to be an excellent research method for glaciological studies. The total ice thickness and englacial structures can be studied, and the method can give information on the temperature regime within the ice. Good velocity profiles are needed to convert measured two-way travel time to depth information. In addition, a good velocity analysis
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Testing of a GPR equipment to assess the integrity condition of a subway tunnel located under groundwater level Near Surf. Geophys. (IF 1.6) Pub Date : 2023-02-15 Federico Lombardi, Maurizio Lualdi
Determining the condition of underground concrete tunnels is fundamental for ensuring continuity and safety of operations, as well as for deploying efficient maintenance plans. The increased traffic volumes in early infrastructures, which are characterized by outdated construction techniques and potential approximated realization, as well as rising groundwater levels due to variations in urban industrialization
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Combination of passive and active methods towards site characterization of accelerometer stations in Greece Near Surf. Geophys. (IF 1.6) Pub Date : 2023-02-12 George Papadopoulos, Ilias Fikos, Antonio Garcia-Jerez, Nikos Theodoulidis, George Vargemezis
The strong correlation between earthquake damage and the local geological conditions in an area has long been established, and site characterization studies are common practice for realistic estimation of seismic hazard and mitigation of the respective seismic risk. Estimation of the time-averaged S-waves velocity of the topmost 30 m (VS30) is recognized as a basic proxy for site characterization and
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Geomechanical parameters assessment and geological characterization using fuzzy C means clustering of electrical resistivity and seismic data Near Surf. Geophys. (IF 1.6) Pub Date : 2023-01-14 Beatriz Benjumea, Anna Gabàs, Albert Macau, Fabian Bellmunt, Juanjo Ledo, Jordi Ripoll, Sara Figueras
A broad understanding of the subsoil characteristics is required to deal with uncertainty in the infrastructure planning phase or even in the diagnosis of infrastructure damage. In this work, electrical resistivity and seismic methods have been employed for lithological characterization and geomechanical parameters assessment. The study area is characterized by high variability in geotechnical characteristics
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Improved Tucker decomposition algorithm for noise suppression of 3D GPR data in road detection Near Surf. Geophys. (IF 1.6) Pub Date : 2022-12-30 Kun Yan, Zhihua Zhang, Xianlei Xu
The echo data of ground-penetrating radar (GPR) have a low signal-to-noise ratio. Denoising and interference suppression are important for improving the accuracy of underground target recognition and detection. In this paper, a new method of noise analysis and suppression of 3D GPR is proposed, transforming the problem of noise reduction into an optimization problem regarding a third-order tensor.
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Preferential flow between rivers and aquifers in alluvial floodplains: A key to modelling and sustainably managing shallow groundwater resources Near Surf. Geophys. (IF 1.6) Pub Date : 2022-12-26 J. Michael Martin, Mark E. Everett, Peter S. K. Knappett, Ryan C. Ewing
Preferential flow between rivers and aquifers in alluvial floodplains may be a core component of shallow groundwater transport and, consequently, its understanding is key to modelling and managing groundwater resources. At a clay wedge separating present-day streamflow and bank storage from an adjacent shallow aquifer, we image a suspected sand-dominated structure. This structure cuts through the clay
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Geophysical mapping of freshwater lens in Big Pine Key, Florida: Electromagnetic Induction Calibration and Application Near Surf. Geophys. (IF 1.6) Pub Date : 2022-12-07 Michael Eyob Kiflai, Dean Whitman
Geoelectric and electromagnetic (EM) methods are rapid and non-invasive geophysical techniques for estimating groundwater properties and characterizing the spatial and temporal variability of subsurface formations. However, to quantitatively interpret the EM data, the systematic error due to calibration problems and random error must be considered. We conducted coincident EM and electrical resistivity
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Common-midpoint cross-correlation stacking tomography: A 3D approach for frequency-dependent mapping of Rayleigh waves, group and phase velocity throughout an active seismic network Near Surf. Geophys. (IF 1.6) Pub Date : 2022-12-07 K. Leontarakis, C. Orfanos, G. Apostolopoulos
Shear-wave velocity constitutes an important characterization parameter in terms of engineering properties. Several techniques of surface wave analysis have been widely adopted for building near-surface 1D, or even 2D, S-wave velocity models, but comparable 3D approaches, such as the surface wave tomography (SWT) method, are usually limited to global or regional seismological studies. Moreover, a reliable
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Application of a global–local full-waveform inversion of Rayleigh wave to estimate the near-surface shear wave velocity model Near Surf. Geophys. (IF 1.6) Pub Date : 2022-12-05 Salvatore Lamuraglia, Eusebio Stucchi, Mattia Aleardi
We present a global–local full-waveform inversion (FWI) of surface waves to estimate a high-resolution shear wave velocity model of the near-surface at the site of Grenoble (France). The seismic data we use have been acquired in the framework of the InterPACIFIC project. A first attempt is made by employing the multichannel analysis of surface waves (MASW) to invert the fundamental modes of Rayleigh
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Experimental study of electrical complex resistivity in a 2D multiphase porous medium under non-isothermal conditions: Application to soil remediation monitoring Near Surf. Geophys. (IF 1.6) Pub Date : 2022-11-23 Mohammad Ali Iravani, Hossein Davarzani, Jacques Deparis, Stéfan Colombano, Nicolas Philippe, Benjarese Oniangue, Roger Guérin, Alexis Maineult
In this decade, electro-geophysical methods are widely used in different environmental subjects. Studies on soil remediation when polluted by dense non-aqueous phase liquids (DNAPLs) has become a certain need for all countries. Geoelectrical methods have shown their potential to facilitate evaluating decontamination processes. Our challenge in this study was to understand how coupled temperature and
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Imaging gypsum–anhydrite interface by a structure-based conceptual resistivity model: A case study from Bala (Turkey) gypsum deposits Near Surf. Geophys. (IF 1.6) Pub Date : 2022-11-15 Irfan Akca, Özlem Hacıoğlu, Ahmet T. Başokur
Principal calcium sulphate rocks, such as gypsum and anhydrite, originate from evaporitic processes. Gypsum is considered an industrial raw material with high economic value, but anhydrite has no economic interest. Therefore, delineating the interface between sedimentary cover and gypsum, and differentiating gypsum from anhydrite has significant importance in the production planning of open pits. An
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Two-dimensional joint inversion of electromagnetic soundings at low induction numbers and direct current resistivity Near Surf. Geophys. (IF 1.6) Pub Date : 2022-10-28 Eliana Vargas Huitzil, Marco Antonio Pérez Flores, Francisco J. Esparza Hernández, Sóstenes Méndez Delgado
Direct current resistivity and electromagnetic methods at low induction numbers are commonly used to characterize near-surface structures. Although both methods are related to the same property, resistivity or conductivity, they have different sensitivities. The electromagnetic method at low induction numbers is more sensitive to conductive structures, but faces problems resolving resistive bodies
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The effects of receiver arrangement on velocity analysis with multi-concurrent receiver GPR data Near Surf. Geophys. (IF 1.6) Pub Date : 2022-08-30 Dimitrios Angelis, Craig Warren, Nectaria Diamanti, James Martin, A. Peter Annan
Determining subsurface electromagnetic (EM) wave velocity is critical for ground-penetrating radar (GPR) data analysis, as velocity is used for the time-to-depth conversion, and hence leads to obtaining the precise location of the objects of interest. Currently, the way to acquire detailed subsurface EM wave velocity models involves employing multi-offset GPR surveys, such as wide-angle reflection-refraction
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Resistivity imaging of river embankments: 3D effects due to varying water levels in tidal rivers Near Surf. Geophys. (IF 1.6) Pub Date : 2022-08-30 John Ball, Jonathan Chambers, Paul Wilkinson, Andrew Binley
Electrical resistivity tomography (ERT) has seen increased use in the monitoring the condition of river embankments, due to its spatial subsurface coverage, sensitivity to changes in internal states, such as moisture content, and ability to identify seepage and other erosional process with time-lapse ERT. Two-dimensional ERT surveys are commonly used due to time and site constraints, but they are often
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Detecting subsea permafrost layers on marine seismic data: An appraisal from forward modelling Near Surf. Geophys. (IF 1.6) Pub Date : 2022-08-13 Mathieu J. Duchesne, Gabriel Fabien-Ouellet, Jefferson Bustamante
Detecting the top and base subsea permafrost from 2D seismic reflection data in shallow marine settings is a non-trivial task due to the occurrence of strong free surface multiples. The potential to accurately detect permafrost layers on conventional 2D seismic reflection data is assessed through viscoelastic modelling. Reflection imaging of permafrost layers is examined through the evaluation of specific
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Site characterization study with microtremor data: A case study at the West Borneo NPP potential site Near Surf. Geophys. (IF 1.6) Pub Date : 2022-08-08 Theo Alvin Ryanto, Eko Rudi Iswanto, Sunarko, Slamet Suryanto, Hadi Suntoko, Yuliastuti, Heni Susiati
A site characterization using a microtremor measurement study was conducted at the West Borneo nuclear power plant (NPP) potential site as a preliminary feasibility study. This study measured the natural resonant frequency of soil and estimated the subsurface VS as prior information for the design planning of an NPP building foundation. The single station microtremor data were processed using the
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Surface deployment of DAS systems: Coupling strategies and comparisons to geophone data Near Surf. Geophys. (IF 1.6) Pub Date : 2022-08-01 Nicholas Harmon, Catherine A. Rychert, John Davis, Gilberto Brambilla, William Buffet, Ben Chichester, Yuhang Dai, Petros Bogiatzis, James Snook, Lieke van Putten, Ali Masoudi
Distributed acoustic sensing (DAS) systems are a recent technological development for seismic observations over a broad range of frequencies with a wide variety of applications. Typically, fibre-optic cables are buried underground or cemented into well casings where the cables are well-coupled to the ground. Quick and temporary surface deployment of cables has great potential utility in areas where
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Characterization of gas-bearing sediments in the coastal environment using geophysical and geotechnical data Near Surf. Geophys. (IF 1.6) Pub Date : 2022-07-09 Judith Dusart, Pascal Tarits, Maud Fabre, Bruno Marsset, Gwenaël Jouet, Axel Ehrhold, Vincent Riboulot, Agnès Baltzer
Seismic investigation in marine gas-bearing sediments often fails to get information below the acoustic mask created by free gas. To circumvent this problem, we combined collocated multichannel ultra-high resolution seismic imaging, marine electrical resistivity tomography and core sampling to study the physical properties of gas-bearing sediments in the Bay of Concarneau (France). We obtained sections
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Full-waveform inversion of surface waves based on instantaneous-phase coherency Near Surf. Geophys. (IF 1.6) Pub Date : 2022-07-09 Munirdin Tohti, Jianhuan Liu, Wenjiao Xiao, Yibo Wang, Qingyun Di, Kefa Zhou
Full-waveform inversion of surface waves can provide high-resolution S-wave velocity (Vs) of the shallow subsurface and is becoming a popular shallow-seismic method. We propose a misfit function based on instantaneous-phase coherency, which can measure the amplitude-unbiased coherency between measured and synthetic data. The instantaneous-phase coherency was once the key component that was used in