Just-Accepted Journal Articles

Just-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

Application of Geoelectrical Methods to Identify the Subsurface Layering Structure of Construction and Demolition Waste Depot
Authors:
Asgar Nasiri, Abolfazl Eslami, Ahmad Fahimifar, and Davood Akbarimehr

DOI: https://doi.org/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 these depots' layering structure and composition can greatly benefit 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 line 4 of the 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 was 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 better understand 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. The results of this study can assist urban management in recycling C&D waste. Recycling C&D waste recovers some economic value from C&D waste, clearing out C&D waste depots and eliminating the environmental desirability issues that they can cause in surrounding areas.

Distortions of Metallic Objects in EM34 Apparent Conductivity Readings

Authors:
Pedro Henrique da Silva Chibane, Caroline Urenha Silva, Carlos Alberto Mendonça, and Ulrich Ofterdinger

Abstract:  Metallic structures are a common noise source in Slingram electromagnetic surveys because they interact with the primary magnetic field generated by the transmitter coil and create a secondary magnetic field that distorts the apparent conductivity readings from a layered or homogeneous subsurface. The main challenge is understanding how their influence varies depending on the loop configuration and the distance at which the surface structure no longer distorts the apparent conductivity readings. We propose a methodology that integrates experimental techniques and numerical modeling to elucidate the distortions induced by a fence-like structure placed at varying distances from the coils of a low-induction conductivity meter. Additionally, we aim to evaluate the model responses using numerical simulations with electromagnetic systems operating at higher frequency ranges. To quantify the distortions in apparent conductivity, we conducted field measurements by keeping the electromagnetic coils in a fixed position while changing the placement of the conductive structure. The readings obtained before installing the conductive structure were used as the background reference response to accurately determine the distortions. The same experimental procedure was tested in terrains with different resistivities to evaluate the changes caused by the same structure in different backgrounds. Our results show that this approach allowed us to infer that the deviations in apparent conductivity caused by the presence of the fence are more noticeable where the background resistivity is higher. However, these deviations were observed only for short distances of about 1/5 to 1/2 of the coil separation for the evaluated targets. The integration between the experimental survey and the numerical modeling suggests that distortion increases when the instrument is operated at induction numbers higher than ∼0.2. For all tested conductivity models and frequency ranges, minor distortions were observed with the vertical coplanar coil configuration compared to the horizontal coplanar configuration for the transmitter-receiver pair. Negligible distortions were observed for fences with unconnected wires, suggesting minor interference from loose metallic objects on the ground surface that do not form closed loops, favoring EM induction.

Electrical Resistivity Inversion Based on Symmetric Polynomial Constraint

Authors:
qikai sun; MAN LI; zhiyong zhang; yihao guo

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

Development of An ANN-based Technique for Inversion of Seismic Refraction Travel Times

Authors:
Rashed Pourmirzaee; Shahab Hoseini

DOI: 10.32389/JEEG22-044

ABSTRACT: Non-uniqueness in inversion of seismic data can be considered as the main challenge for application of such data. To control this problem, prior information such as downhole data should be used. However, in most cases, prior information is not available; accordingly, geophysicists/analysts have to suppose a primary model for the observed data, and then find the final adequate layered earth model through trial and error. In this study, a new technique was developed based on artificial neural network (ANN) for inversion of seismic refraction data in the absence of prior information. In this regard, a sequential multilayer perceptron (SMLP) was proposed which integrates the sequential information of the model parameters to predict a reasonable layered earth model. In fact, at first, a multilayer perceptron (MLP) was trained by synthetic data; then, a layered earth model, i.e. primary model, was predicted for the observed data. Next, using the primary model, a range for each of the model parameters, i.e. thickness and P-wave velocity, for each layer was defined. Subsequently, new synthetic samples were generated based on the determined ranges. Finally, using another MLP, which was trained by the new synthetic samples, the final model for the observed data was estimated. The proposed method was also tested employing different synthetic data with and without noise. Moreover, the SMLP inversion technique was used in analyzing the experimental seismic refraction dataset at a dam construction site. The results for both synthetic and experimental data confirmed the reliability of the proposed SMLP inversion technique.

Keywords: Sequential multilayer perceptron; travel times; Inversion; prior information

Characterization of a small abandoned municipal solid waste scattered landfill combining remote sensing and near-surface geophysical investigations

Authors:
Grégory Bièvre; Stéphane Garambois

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

Seismic swell effect correction using GVF-based guide-line

Authors:
Kyoungmin Lim; Jiho Ha; Jungkyun Shin; Sungryul Shin; Wookeen Chung

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:
YOUNGFO CHANG; Wei-Zhih Chang; Lun-Tao Tong

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

Influence of Radiative Components and Meteorological Conditions on Simulation of Slope-Specific Heat Balance
Authors:  Mito Nishioka; Megumi Yamashita; Hirotaka Saito

DOI: 10.32389/JEEG22-011

ABSTRACT:  Fields have uneven surfaces, such as ridges, and the shortwave radiation of fields differs depending on the orientation of the slope of the unevenness, resulting in variations in the distribution of moisture on the ground surface. Therefore, it is necessary to estimate the heat and water balances spatially, taking into account the variation of the moisture distribution on the ground surface. Previously, one-dimensional simulations have been used to estimate the heat and water balance of non-sloping surfaces. To estimate the heat and water balance spatially while taking into account ground surface roughness, it is necessary to first estimate the heat and water balance of the ground surface on the basis of slope orientation. The purpose of this study was to clarify those factors, in addition to shortwave radiation, that affect the heat balance of a bare sloping surface at different orientations. To achieve this, the heat balance calculated using observational data of bare ground, including unevenness, was compared with the heat balance estimated by HYDRUS-1D simulation for each slope orientation. Additionally, the brightness index of RGB images was calculated and compared with the relative ground surface brightness and the estimated heat balance for each slope orientation. The estimated results at night and at sunrise/sunset were extremely small in comparison with the calculated results, and the heat balance simulation in the absence of shortwave radiation remained an issue. The relationship between ground surface brightness and ground conduction heat was completely different depending on slope direction, suggesting that ground surface heat transfer is affected substantially by factors other than shortwave radiation related to slope orientation. The findings indicate that it is necessary to examine the effects of heat transfer in detail to estimate the heat balance related to slope orientation.

Keywords: Heat balance; Net radiation; Slope orientation; Monitoring; HYDRUS-1D