scholarly journals Electrical resistivity tomography applied to geologic, hydrogeologic, and engineering investigations at a former waste-disposal site

Geophysics ◽  
2006 ◽  
Vol 71 (6) ◽  
pp. B231-B239 ◽  
Author(s):  
Jonathan E. Chambers ◽  
Oliver Kuras ◽  
Philip I. Meldrum ◽  
Richard D. Ogilvy ◽  
Jonathan Hollands
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Site Investigation ◽  
High Resistivity ◽  
Potential Zone ◽  
Resistivity Tomography ◽  
L2 Norm ◽  
Resistivity Model ◽  
2D And 3D ◽  
2D Resistivity

A former dolerite quarry and landfill site was investigated using 2D and 3D electrical resistivity tomography (ERT), with the aims of determining buried quarry geometry, mapping bedrock contamination arising from the landfill, and characterizing site geology. Resistivity data were collected from a network of intersecting survey lines using a Wenner-based array configuration. Inversion of the data was carried out using 2D and 3D regularized least-squares optimization methods with robust (L1-norm) model constraints. For this site, where high resistivity contrasts were present, robust model constraints produced a more accurate recovery of subsurface structures when compared to the use of smooth (L2-norm) constraints. Integrated 3D spatial analysis of the ERT and conventional site investigation data proved in this case a highly effective means of characterizing the landfill and its environs. The 3D resistivity model was successfully used to confirm the position of the landfill boundaries, which appeared as electrically well-defined features that corresponded extremely closely to both historic maps and intrusive site investigation data. A potential zone of leachate migration from the landfill was identified from the electrical models; the location of this zone was consistent with the predicted direction of groundwater flow across the site. Unquarried areas of a dolerite sill were imaged as a resistive sheet-like feature, while the fault zone appeared in the 2D resistivity model as a dipping structure defined by contrasting bedrock resistivities.

Assessment of Chromium Waste Contamination by Electrical Resistivity Tomography: A Case Study

2019 ◽  
Vol 24 (1) ◽  
pp. 163-167
Author(s):  
Yuling Wang ◽  
Ya Xu ◽  
Changxin Nai ◽  
Lu Dong
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Soil Analysis ◽  
Soil Samples ◽  
Production Plant ◽  
Resistivity Tomography ◽  
Groundwater Sampling ◽  
Resistivity Model ◽  
Main Production ◽  
2D Resistivity

This study aims to determine the chromium contamination at an abandoned chemical factory by electrical resistivity tomography (ERT). Five ERT survey lines were conducted in the main production plant and two boreholes were drilled to collect soil samples for soil analysis. The 2D and 3D resistivity model were constructed to evaluate the pollution plumes. The ERT results showed that seven low-resistivity zones are observed in the 2D resistivity profiles, which may indicate the main pollution areas at the site. The 3D electrical resistivity model further showed that the soil pollution is more severe in the southwest than in the other areas of the site. The ERT results were partly verified by chemical analysis of soil samples. These ERT results can be further used for additional designs of soil and groundwater sampling.

Internal structure and conditions of permafrost mounds at Umiujaq in Nunavik, Canada, inferred from field investigation and electrical resistivity tomography

2008 ◽  
Vol 45 (3) ◽  
pp. 367-387 ◽  
Author(s):  
Richard Fortier ◽  
Anne-Marie LeBlanc ◽  
Michel Allard ◽  
Sylvie Buteau ◽  
Fabrice Calmels
Keyword(s):  
Electrical Resistivity ◽  
Internal Structure ◽  
Prior Information ◽  
Electrical Resistivity Tomography ◽  
Reference Model ◽  
High Resistivity ◽  
Unfrozen Water ◽  
Resistivity Tomography ◽  
Unfrozen Water Content ◽  
Resistivity Model

A systematic approach was used for the interpretation of the electrical resistivity tomography carried out on two permafrost mounds at Umiujaq in Nunavik, Canada, to assess their internal structure and conditions. Prior information under the form of a geocryologic model of the permafrost mounds was integrated in the inversion of the pseudo-section of apparent electrical resistivity. The geocryologic model was developed from the synthesis of previous field investigations, including shallow and deep sampling, temperature and electrical resistivity logging, and cone penetration tests performed in the permafrost mounds. Values of electrical resistivity were ascribed to the different layers making of the geocryologic model to define a synthetic resistivity model of the permafrost mounds used as a reference model to constrain the inversion. The constrained resistivity model clearly show the presence of ice-rich cores in the permafrost mounds underscored by high resistivity values in excess of 30 000 Ωm, while the unfrozen zones surrounding the permafrost mounds are characterized by resistivity values lower than 1000 Ωm. The spatial distribution of unfrozen water and ice contents in the permafrost mounds were also assessed according to empirical relationships between the electrical resistivity and water contents. The ice content is highly variable and can be as high as 80% in the ice-rich cores, while the unfrozen water content varies between 2% and 5%. The integration of prior information in the inversion process leads to a more realistic constrained resistivity model showing sharp resistivity contrasts expected at the boundaries such as the permafrost table and base.

scholarly journals Andesite prospect at West Sungkai of North Lampung: Its distribution based on electrical resistivity tomography

2021 ◽  
Vol 882 (1) ◽  
pp. 012086
Author(s):  
R. M. Antosia ◽  
Mustika ◽  
I. A. Putri ◽  
S. Rasimeng ◽  
O. Dinata
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Research Area ◽  
Inversion Method ◽  
Reserve Estimation ◽  
Linear Inversion ◽  
Resistivity Tomography ◽  
Resistivity Model ◽  
Subsurface Resistivity ◽  
2D And 3D

Abstract Infrastructure construction made andesite’s demand has increased, particularly in Lampung Province. In this research, its distribution in West Sungkai of North Lampung is mapped based on Electrical Resistivity Tomography (ERT) data from 6 lines, each of them was 186 m in length. Due to its excellent vertical resolution, Wenner configuration is performed. The research area is part of Quarter Holocene Volcanic (Qhv) formation. Lajur Barisan members consist of volcanic breccia, lava, and andesite-basalt tuff; thus, resistivity modeling is built within this aisle. Subsurface resistivity model has been created using the non-linear inversion method with promising low error at the third to fifth iterations, which marks an acceptable value. Using 2D and 3D ERT modeling, it is estimated that there are three mains of rocks based on their resistivity value: sandy tuff with 65 – 212 Ω m; tuff with 212 – 655 Ω m; and andesite with resistivity more than 655 Ω m. Andesite within this area is likely lava andesite which spread from the middle to the West and north. It is located at 5 – 35 m in depths with the reserve estimation of andesite is about 1.65 million tons.

Using resistivity or logarithm of resistivity to calculate depth of investigation index to assess reliability of electrical resistivity tomography

Geophysics ◽  
2017 ◽  
Vol 82 (5) ◽  
pp. EN93-EN98 ◽  
Author(s):  
Simon D. Carrière ◽  
Konstantinos Chalikakis ◽  
Charles Danquigny ◽  
Laura Torres-Rondon
Keyword(s):  
Electrical Resistivity ◽  
Comparative Study ◽  
Electrical Resistivity Tomography ◽  
High Resistivity ◽  
Resistivity Tomography ◽  
Direct Modeling ◽  
Resistivity Model ◽  
Synthetic Models ◽  
Depth Of Investigation

We have conducted a comparative study to determine the most efficient and reliable way to calculate the depth of investigation (DOI) index to assess the quality of electrical resistivity tomography models. We compared the results of using resistivity and logarithm of resistivity after testing them on four synthetic models by direct modeling and a field case, in which the resistivity model was validated by auger drillings. We tested the two most commonly used acquisition arrays, dipole-dipole, and Wenner-Schlumberger. The index calculated with the logarithm of resistivity clearly appears to be more satisfactory than the resistivity-based index. The method based on resistivity systematically overestimates risk (high DOI) in areas of high resistivity, and it underestimates risk in conductive zones. As a result, we strongly recommend the use of the logarithm of inverted resistivity to calculate the DOI index.

scholarly journals CONTRIBUTION OF DEEP ELECTRICAL RESISTIVITY TOMOGRAPHY TECHNIQUE TO HYDROGEOLOGICAL STUDIES: CASES FROM AREAS IN KAVALA (NORTH GREECE)

2017 ◽  
Vol 43 (4) ◽  
pp. 1962
Author(s):  
G. Vargemezis ◽  
P. Tsourlos ◽  
I. Mertzanides
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Geological Structure ◽  
Resistivity Tomography ◽  
Near Surface ◽  
Resistivity Method ◽  
Area Of Interest ◽  
Vertical Electric Sounding ◽  
Hydrogeological Studies ◽  
2D And 3D

The most common geophysical method widely used in hydrogeological surveys concerning deep investigations (150-300m of depth) is the resistivity method and particularly the Vertical Electric Sounding (VES) using the Schlumberger array. VES interpretations assume 1D geoelectrical structure yet it is obvious that such an interpretation assumption is not valid in many cases where 2D and 3D geological features exist. In such cases the application of geoelectrical techniques which can provide both vertical and lateral information concerning the resistivity variations is required. Techniques such as the electrical resistivity tomography, mostly used for the 2D and 3D geoelectrical mapping of near surface applications can be adapted to be used for larger investigation depths provided that modified equipment (viz. cables) is used. In the present paper, the application of deep electrical resistivity tomography (ERT) techniques is applied. ERT array of 21 electrodes, at a distance of 50 meters between them (total length 1000 meters) has been used in several studied areas located in the prefecture of Kavala (North Greece). In several cases near surface structure has been compared with VLF data. The aim of the survey was to study in detail the geological-hydrogeological structure the area of interest in order to suggest the best location for the construction of hydrowells with the most promising results. The 2D images of the geological structure down to the depth of at least 200 meters allowed the better understanding of the behaviour of layered geological formations, since in several cases resistivity values have been calibrated with data from pre-existing boreholes.

scholarly journals Exploring the regolith with electrical resistivity tomography in largescale surveys: electrode spacing related issues and possibility

2020 ◽  
Author(s):  
Laurent Gourdol ◽  
Rémi Clément ◽  
Jérôme Juilleret ◽  
Laurent Pfister ◽  
Christophe Hissler
Keyword(s):  
Electrical Resistivity ◽  
Apparent Resistivity ◽  
Large Scale ◽  
Electrical Resistivity Tomography ◽  
Subsurface Layer ◽  
Electrode Spacing ◽  
High Resistivity ◽  
Constant Thickness ◽  
Resistivity Tomography

Abstract. Within the Critical Zone, regolith plays a key role in the fundamental hydrological functions of water collection, storage, mixing and release. Electrical Resistivity Tomography (ERT) is recognized as a remarkable tool for characterizing the geometry and properties of the regolith, overcoming limitations inherent to conventional borehole-based investigations. For exploring shallow layers, a small electrode spacing (ES) will provide a denser set of apparent resistivity measurements of the subsurface. As this option is cumbersome and time-consuming, smaller ES – albeit offering poorer shallow apparent resistivity data – are often preferred for large horizontal ERT surveys. To investigate the negative trade-off between larger ES and reduced accuracy of the inverted ERT images for shallow layers, we use a set of synthetic conductive/resistive/conductive three-layered soil–saprock/saprolite–bedrock models in combination with a reference field dataset. Our results suggest that an increase in ES causes a deterioration of the accuracy of the inverted ERT images in terms of both resistivity distribution and interface delineation and, most importantly, that this degradation increases sharply when the ES exceeds the thickness of the top subsurface layer. This finding, which is obvious for the characterization of shallow layers, is also relevant even when solely aiming for the characterization of deeper layers. We show that an oversized ES leads to overestimations of depth to bedrock and that this overestimation is even more important for subsurface structures with high resistivity contrast. To overcome this limitation, we propose adding interpolated levels of surficial apparent resistivity relying on a limited number of ERT profiles with a smaller ES. We demonstrate that our protocol significantly improves the accuracy of ERT profiles when using large ES, provided that the top layer has a rather constant thickness and resistivity. For the specific case of large-scale ERT surveys the proposed upgrading procedure is cost-effective in comparison to protocols based on small ES.

scholarly journals Cross-Section Resistivity Detection of Tree (Swietenia Magahoni and Gmelina) Using ERT Method

2022 ◽  
Vol 8 (1) ◽  
pp. 39-44
Author(s):  
Evi Fazriati ◽  
Asep Purnama ◽  
Gian Agistian Algifari ◽  
Irene Siti Amilah Muslimah ◽  
Fitria Hapsari Puteri Sumanto ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Cross Section ◽  
Electrical Resistivity Tomography ◽  
Nondestructive Method ◽  
Resistivity Tomography ◽  
Living Tree ◽  
Value Range ◽  
2D Resistivity ◽  
Swietenia Mahagoni ◽  
Monitoring Activity

The existence of trees is very beneficial for humans’ life. There are utilizations of tree such as urban planning and reforestation. However, the tree can be dangerous when the tree is aged and decay because of several factors that might be cause fallen tree. Furthermore, the monitoring activity is needed to know the condition of the tree. One of the methods that can be used to detect hollow in living tree is Electrical Resistivity Tomography (ERT). The ERT is an efficient and nondestructive method that can be potential to estimate resistivity cross section. The measurement of ERT conducted on Swietenia mahagoni and Gmelina with unhealthy and healthy condition visually. The data processed using Res2Dinv and reconstructed for obtaining 2D resistivity cross section. The results shows that the unhealthy Swietenia mahagoni has logarithmic resistivity value range between 0.1-1 Ωm and the healthy Swietenia mahagoni has 1-4 Ωm. Meanwhile, the unhealthy and healthy Gmelina has logarithmic resistivity value range between 0.5-4.5 Ωm and 0.5-3 Ωm, respectively. It is shows that the tree indicated health visually from biological view does not mean the tree is decay. It might be influenced by phenology factor and/or the species of the tree.

scholarly journals Stabilization Methodology in Foundation Soils by ERT-3D Application in Estepona, South Spain

2021 ◽  
Vol 11 (10) ◽  
pp. 4455
Author(s):  
Alfonso Gutiérrez-Martín ◽  
José I. Yenes ◽  
Marta Fernández-Hernández ◽  
Ricardo Castedo
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Shallow Foundations ◽  
Simplified Model ◽  
High Resistivity ◽  
Combined System ◽  
Resistivity Tomography ◽  
Field Campaign ◽  
Non Invasive ◽  
Dipole Configuration

The paper proposes a novel methodology for the stabilization of shallow foundations, with a simplified model combined with 3D electrical resistivity tomography (ERT-3D and consolidation injections. To determine its usefulness, the method has been applied in a case located in Estepona (southern Spain). The chosen tomography model is the dipole–dipole configuration, with an optimized distance between electrodes of 0.80 m for a better visualization of the foundation subsoil; with this parameterization, a total of 72 electrodes were installed in the analyzed case. In this work, the depth of the anomaly in the building’s supporting subsoil was detected ranging from 2.00 m to 3.90 m deep. The study also delineates areas of high resistivity variations (50–1000 Ω m) in the middle and eastern end of the field. These data have been validated and corroborated with a field campaign. The results of the ERT-3D monitoring are presented, once the investment data has been processed with the RES3DINV software, from the beginning to the end of the stabilization intervention. The novelty occurs with the interaction between the tomography and the foundation consolidation injections, until the final stabilization. This is a very useful methodology in case of emergency consolidation, where there is a need to minimize damage to the building. Thus, people using this combined system will be able to practically solve the initial anomalies of the subsoil that caused the damages, in a non-invasive way, considerably lowering the value of the resistivities.

scholarly journals Electrical Resistivity Tomography And Induced Polarization Study For Groundwater Exploration In The Agricultural Development Areas of Brunei Darussalam

2021 ◽  
Author(s):  
Lieyana Azffri ◽  
Stefan Herwig Gödeke ◽  
Mohammad Faizan Ibrahim
Keyword(s):  
Electrical Resistivity ◽  
Agricultural Development ◽  
Electrical Resistivity Tomography ◽  
Groundwater Exploration ◽  
Induced Polarization ◽  
Resistivity Tomography ◽  
Well Drilling ◽  
Brunei Darussalam ◽  
Groundwater Yield ◽  
2D Resistivity

Abstract Electrical Resistivity Tomography (ERT) and Induced Polarization (IP) study was carried out for groundwater exploration at eight agricultural development areas in Brunei Darussalam. The study was undertaken to meet the growing demands of water supply in the Brunei agricultural sector, particularly for paddy field irrigation. A total of nineteen survey lines with survey lengths of up to 800 m and investigation depths of up to 150 m below ground level were conducted to delineate subsurface geological structures, formations and aquifer zones in the study area. Aquifer zones with resistivity values ranging from 1 to 100 ohm-m and chargeability values of less than 1 mV/V were detected in all surveyed locations. New groundwater well drilling was conducted at two of the surveyed sites based on interpretations of 2D resistivity and chargeability inversion models. Water well drilling encountered aquifer zones, which were primarily in sandy layers. Hydraulic tests revealed groundwater yields of 4.3 and 288 m³/day. Estimated transmissivity values of the aquifer units based on pumping tests are 0.53 and 109 m²/day, while their hydraulic conductivity values are 0.05 and 2.75 m/day. Estimated parameters of the aquifer units indicate weak to moderate groundwater yield for withdrawal and distribution for irrigation purposes at the investigated sites. The present study helped decision-makers take suitable measures for placing future irrigation wells and achieve significant groundwater exploration results in the study area.

Sign in / Sign up

Export Citation Format

Share Document