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Just-Accepted Journal ArticlesJust-Accepted Articles are peer-reviewed, accepted manuscripts that have been assigned Digital Object Identifiers (DOIs) and undergo the normal publication process (copy editing, page composition, proofing by author, and finalization). A Just-Accepted article listing includes an abstract and the DOI (scroll). The article is removed when the final version of the manuscript is ready and assigned to a Journal of Environmental & Engineering Geophysics (JEEG) issue, becoming the official version of the article. The Just Accepted article has the same DOI that appears on the official version of the article; therefore, citations made to an article during the Just-Accepted stage will continue to link to the article's official version. EEGS Members can access the full, preliminary article via this "member-only" link: Just-Accepted Articles with full article PDF Electrical Resistivity Inversion Based on Symmetric Polynomial Constraint Authors: DOI: 10.32389/JEEG23-028 ABSTRACT: As we seek to make geophysical models more consistent with geological models, more and more a priori information is incorporated into geophysical inverse problems. How we make the most use of a priori information is still a key issue in geophysical inversion, particularly for effectively representing such information in inversion problems. To address this problem, we propose a symmetric polynomial constrained inversion algorithm that can represent multiple known physical properties for the lithology. The electrical resistivity synthetic model tests show that the inversion results constrained with symmetric polynomials can make the model resistivity be in line with a priori information and obtain more realistic sharp boundaries. Finally, we give a practical verification of our inversion algorithm with field data. Keywords: Electrical resistivity; Inversion; Symmetric polynomial; rock physical properties Applying Particle Swarm Optimization on VES Data for Groundwater Evaluation Authors: DOI: 10.32389/JEEG24-003 ABSTRACT: This research addresses groundwater management challenges in southeastern Punjab Province, Pakistan, focusing on over-exploitation, contamination, and climate change impacts. Employing a multidisciplinary approach, it integrates hydro geology, ecology, economics, and policy studies. The study emphasizes particularly on vertical electrical sounding (VES) enhanced with Particle Swarm Optimization (PSO) algorithm and other advanced electrical geophysical techniques. This innovative method improves VES data inversion, vital for understanding aquifer characteristics and identifying salinity-free zones, supporting sustainable groundwater strategies. Covering 200 square kilometers in the Indus Plain, an area with alluvial deposits from the Ravi and Beas rivers, the research offers insight into complex groundwater dynamics. PSO's efficiency in generating accurate resistivity models is key for locating new wells, ensuring water availability and sustainable agriculture. The methodology includes aquifer parameters, borehole logs, and analysis of aquifer properties and salinity distribution, mapping crucial aquifer features to assess groundwater potential and contamination risks. Keywords: Vertical Electrical Sounding (VES); Inversion; Particle Swarm Optimization; Aquifer Geohydraulic Properties; Groundwater Evaluation Development of An ANN-based Technique for Inversion of Seismic Refraction Travel Times Authors: Application of Geoelectrical Methods to Identify the Subsurface Layering Structure of Construction and Demolition Waste Depot Authors: DOI: 10.32389/JEEG22-025 ABSTRACT: In large cities with a growing population, the expansion of construction, and demolition (C&D) waste of buildings can lead to the annual production of millions of tons of waste. Any solution for inexpensive, rapid, and accurate identification of the layering structure and composition of these depots can be of great benefit to urban management. Geoelectric methods can serve as a simple, cost-effective, and sufficiently accurate means of identifying these materials. In this study, the layering structure of C&D waste buried in the line 4 of Hesar landfill in Karaj city, Iran, was determined using a geoelectric method involving the assessment of electrical resistivity variations in both vertical and horizontal directions. Wenner-Schlumberger array were utilized for the measurements and 2,870 electrical resistivity points were collected. RES2D-INV software was utilized to interpret the data and plot geological sections. In addition, a series of laboratory tests including Sieve analysis and water content were performed on samples collected by continuous core boring to gain a better understanding of the waste composition. According to the study results, compared to the field data, it was concluded that the ERT could accurately predict the changes in various soil layers, aggregate sizes, and water content. In addition, data from boreholes revealed that most of the materials buried in this depot are concrete. Characterization of a small abandoned municipal solid waste scattered landfill combining remote sensing and near-surface geophysical investigations Authors: DOI: 10.32389/JEEG23-002 ABSTRACT: This study reports the combination of remote sensing and ground geophysical techniques to locate an abandoned and hidden municipal solid waste landfill located in a fluvial plain in the French Western Alps. Following earthworks and further floods that eroded into the river bank, wastes made of a mixture of plastic, metal and soil/earth, were uncovered and some of them flowed into the river. The existence of an abandoned landfill, several decades-old, was known, but the knowledge of its exact location was forgotten. Historic aerial photographs back to 1948 allowed delineation in space and time of the location of a platform that was used for landfill operations between around 1973 and 1983. A LiDAR DEM acquired in 2012 allowed was used to locate topographic depressions 0.1 to 0.4 m in depth, notably inside the platform. These depressions are interpreted as resulting from differential compaction originating from the presence of compressible wastes. Geophysical mapping techniques (magnetic and electromagnetic) confirmed the presence of anomalies inside the identified platform. Geophysical imaging techniques (ground-penetrating radar, electrical resistivity tomography) provided a quantitative evaluation of the width and depth of the individual pits. The combination of the different techniques allowed for estimating the first-order volume of waste. The methodology adopted in this work is applicable to detect landfills exhibiting differential compaction and physical contrasts. Keywords: Municipal solid wastes; aerial photographs; LiDAR; near-surface geophysical methods GPR with a Bench Model Experiment to Measure Bathymetry and Sediment Accumulation of Faylor Lake, PA Authors: DOI: 10.32389/JEEG22-033 ABSTRACT: Waterborne GPR can be a powerful method for surveying bathymetry, water, and sedimentation volumes within water impoundments like Faylor Lake in Snyder County, Pennsylvania. Current methods for measuring sediment volume in water impoundments often involve invasive techniques, such collecting cores, which lead to rough estimates due to limited available physical data. The objective of this study is to utilize a custom-made GPR apparatus, which includes a 100 MHz transceiver, a GPR controller, and a GPS device, all mounted on a small 2-person crewed inflatable watercraft. Over 40,000 data points of depth locations spanning the entire lake were collected. Data has been used to generate contour maps and 3D models of the current bathymetry, as well as the original topography of the basin prior to the construction of the dam in 1983. During this study, the dielectric permittivity of the lacustrine deposit was directly measured using a laboratory bench experiment with a 1600 MHz GPR transceiver. The measured ε =51.69 has enabled the determination of accurate depth values and, subsequently, the sediment volume. The sediment volume was found to represent 20% of the entire lake, with a volume of 139,281 m3. Additionally, the water volume was determined with ε = 80, amounting to 663,659 m3. The 3D bathymetry map has also shown the outlines of the old Middle Creek channel. The deepest part of the lake was identified on the southeast side, near the drop inlet of the dam, along the old Middle Creek channel, with an average depth of 1.63m. Keywords: Bathymetry; GPR; Dielectric; sub-bottom profiling; Faylor Lake Seismic swell effect correction using GVF-based guide-line Authors: DOI: 10.32389/JEEG23-009 ABSTRACT: Swells in marine seismic data disrupt the continuity of the reflection events and makes interpretation difficult. The swell effect removal process consists of sea-bottom detection and correction, which removes the swell effect by shifting the detected sea-bottom signal to the known or estimated seafloor location. The quality of correction depends on the accuracy of the sea-bottom detection. Since general sea-bottom signal detection techniques have been applied directly after pre-processing, a number of mispick scenarios exist due to the characteristics of the data, and additional processes are needed. In this study, we propose a process for accurate detection of sea-bottom reflection signals using the guide-line. The errors are caused by mistaking other reflection events as sea-bottom signals. The guide-line can improve the accuracy of detection by providing rough event times of sea-bottom reflection. The guide-line was extracted from the gradient vector flow (GVF) technique, which is a segmentation method in the image processing field. In the GVF data, the seafloor signals are smoothed and the energy is focused on the sea-bottom. The threshold method was used to detect sea-bottom signals in the range after the guide-line. To attenuate the swell effect, the detected signals were shifted to estimated seafloor locations. The GVF-based guide-line (GVF-GL) method was applied in field data acquired by the airgun and chirp sources with different frequencies. The sea-bottom location was successfully detected and the continuity of the sea bottom and subsurface signals on the section was improved. Keywords: swell effect correction, sea-bottom detection, gradient vector flow (GVF), guide-line, threshold Detect multiple-set fractures by crosshole seismic tomography for using in environmental and engineering geophysics Authors: DOI: 10.32389/JEEG22-037 ABSTRACT: Crosshole seismic tomography (CST) could be used to reconstruct the velocity section of media between two holes. One of the commonly used attributes of fractures reflected in seismic waves is the anisotropy of velocity. Therefore, in this study, the multiple symmetry axes of anisotropic media are utilized to simulate the multiple-set fractures in strata. The anisotropic algebraic reconstruction technique (AART) and anisotropic simultaneous iterative reconstruction technique (ASIRT), which are extensions of isotropic ART and SIRT, are used to detect the medium with multiple symmetry axes and strong anisotropy. Full coverage of ray paths in azimuth is needed for these techniques. The performances of these techniques are tested by the numerical and physical modeling. Testing results show that the multiple-set fractures can be successfully detected by the proposed AART and ASIRT methods when the number of observed data exceeds the number of estimated parameters. However, in complexly anisotropic and heterogeneous media, if the number of estimated parameters is equal to or greater than the number of observed data, the estimation error will significantly increase for using these techniques. Keywords: anisotropy; multiple-set fractures; crosshole seismic tomography Shear Properties and Pore Characteristics of Soil-rock Mixture under Dry-wet cycling Authors: DOI: 10.32389/JEEG22-041 ABSTRACT: The mechanical properties of soil-rock mixtures can deform significantly under the influence of dry-wet cycles, affecting the safety of high-fill projects. A drying device was developed to perform direct shear tests on the soil-rock mixture (S-RM). Large-scale direct shear tests were carried out under the action of dry-wet cycling to study the effect of dry-wet cycling on the mechanical properties of S-RM. Image J software was used to identify the number and area of pores in the binary image, and the pore characteristics of S-RM under dry-wet cycles were analyzed. The results show that the section of post-peak in the shear stress-strain curve is softening under the natural state (no dry- wet cycles), but it is plasticizening under application of the dry-wet cycles. The cohesion of the S-RM particles is affected by the dry-wet cycling and decreases greatly under the first dry-wet cycle, and then decreases gradually for each successive cycle, after which it stabilizes during the fifth dry-wet cycle. The internal friction angle is not affected to a large degree. The effect of a dry wet cycle on pores with different areas is significantly different. The pores with initial sizes of 0.5–10 mm2 decrease, while pores with other initial sizes are hardly affected by the dry-wet cycling. This paper quantitatively analyzed the relationship between the surface two-dimensional porosity and the cohesion and peak strain of S-RM. Keywords: Soil-rock mixture (S-RM); Dry-wet cycle; Shear behavior; Porosity; Quantitative analysis Field evaluation of two impulsive downhole seismic sources in crosswell and reverse VSP geometries and high-resolution characterization of near-surface Texas Gulf Coast sediments Authors: ABSTRACT: Borehole seismic methods have been widely used for characterizing the shallow subsurface. Accurate analysis of their data is aided by a solid understanding of the borehole sources’ characteristics. This study presents a field evaluation of two impulsive borehole seismic sources, (Trident's Scorpion sparker and RT Clark's Ballard weight drop) in crosswell and reverse vertical seismic profile (RVSP) geometries at a Gulf of Mexico coastal site with two shallow vertical wells. The data is then utilized to characterize the near-surface coastal sediments. The Scorpion source generated P-wave dominant frequencies that were recorded as 650 Hz and 250 Hz in the crosswell and RVSP geometries respectively. For Ballard source in the two geometries, the P-wave dominant frequencies were 1100 Hz and 250 Hz. We were also able to pick direct S-wave arrivals with the Ballard source and their dominant frequencies were 100 Hz and 40 Hz for in situ and surface recordings respectively. The average signal-to-noise ratio (SNR) recorded with the Scorpion data for the crosswell geometry and RVSP respectively is 13 and 6, and for the Ballard source 62 and 30. We also investigated the source radiation patterns and signature wavelets. Seismic tomography was performed for the area between the two wells. Low P-wave and S-wave velocities correspond to three fresh water-saturated sand zones identified from drilling cuttings and previous well log data. A Vp-Vs plot also fits reasonably to the Mudrock Line. Both sources can excite repeatable seismic signals up to 150m away and be useful in many geotechnical settings. Validation and Potential Improvement of Soil Survey Maps Using Proximal Soil Sensing Authors: Felippe Hoffmann Silva Karp; Viacheslav I. Adamchuk; Alex Melnitchouck; Barry Allred; Pierre Dutilleul; Luis R. Martinez Influence of Radiative Components and Meteorological Conditions on Simulation of Slope-Specific Heat Balance Research on Time-domain Airborne EM Full-field Apparent Resistivity Imaging Method for Arbitrary Transmitting Waveform Authors: Jianbo Zheng; Yanfu Qi DOI: 10.32389/JEEG22-023 ABSTRACT: The time-domain airborne electromagnetic (AEM) system can do fast EM surveys over mountainous areas by carrying its detection equipment on an airplane. Due to the dense sampling of AEM method, it generates a huge amount of data. As a result, the resistivity imaging methods have become the first choice for data interpretation because they are fast. However, the traditional imaging methods do not fully consider the influence of the transmitting waveform. When they are used to deal with the AEM data with complex current waveform, the imaging results are seriously affected. Therefore, we develop a universal full-field apparent resistivity imaging method for AEM data with arbitrary transmitting waveform. Firstly, we calculate the convolution of time derivative of the current waveform and step response to obtain the time-domain AEM response of the arbitrary transmitting waveform. Then the full-field apparent resistivity imaging method based on the inverse function theorem is used to complete the rapid imaging of AEM data with complex waveform. Finally, we apply our imaging codes to both synthetic and field data to verify its correctness. Keywords: Time-domain; Airborne EM; Transmitting waveform; Full-field apparent resistivity. Noise Reduction of Aeromagnetic Data Using Artificial Neural Network Authors: Osama Elghrabawy DOI: 10.32389/JEEG22-013
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