Wenner Configuration Research Articles

Pendugaan Aliran Conduit Sistem Akuifer Kawasan Karst Gua Pindul Gunung Kidul Menggunakan Metode Geolistrik Konfigurasi Wenner

Karst areas contain limestone lithology that is easily dissolved by water, so rainwater can accelerate the process of dissolving rocks below the surface and forming cavities. The hydrological system of the Pindul area has a conduit flow karst aquifer type. The components of conduit flow are open channels and pipe-like passages that have various shapes. The distribution and direction of conduit flow control the Pindul Cave karst aquifer system in Gunung Kidul. The wenner configuration resistivity geoelectric method can determine the presence of a subsurface—conduit flow in karst areas by knowing the difference in rock-specific resistance values. Resistivity geoelectric measurements were carried out using 8 tracks with each track length of 200 meters. The results of data processing and interpretation of the resistivity cross-section show the presence of conduit flow in 5 passes with a resistivity value of 0.174-25 Ωm. The results of the study can provide an overview to determine the subsurface river area.

A COMBINED METHOD OF 1D AND 2D RESISTIVITY FOR GROUNDWATER LAYER ESTIMATION AT A FARMING AREA IN REJOMULYO VILLAGE

The groundwater depends on when it is available, more in the rainy and less in the dry seasons. Fluctuation in water availability is a significant problem in activities continuously requiring large amounts of water, such as agriculture. Hence, it is necessary to increase the number of water resources to meet the community's needs. Therefore, the groundwater layer zone was estimated as an initial study at the dry farmland in Rejomulyo village, Jati Agung district, South Lampung, using a combined method between the 1D resistivity method of the Schlumberger array and the 2D form of the Wenner configuration. Each sounding point and the 2D line have a maximum stretch length of 300 m. The 1D outcome correlates to the 2D data processing result to produce a subsurface lithology model. As a result, the research area has three primary layers with three rock types. The first layer has a resistivity value of less than 20 Ωm and is identified as tuffaceous clay. Then the second layer with a resistivity range of 60–66 Ωm is tuffaceous sand, this rock which is referred to as the groundwater layer with a depth of 11-40 m. The last layer has a high resistivity value of 120–141 Ωm as tuff. Based on the results of 3D visualization, the groundwater layer in the study area spreads to the southeast with a confined aquifer type. This targeted rock layer can be utilized for groundwater production.

Identification of Weak Zones in the Area of Sigi Regency Office Using Geoelectric Methods of Resistivity

Research has been conducted with the title of identification of weak zones in the Sigi Regency office area using geoelectric methods of resistivity. The study aims to analyze the perlapission of subsurface rocks and determine the distribution of weak zones. The measurements were made on 15 track using the Wenner Configuration. The data obtained is calculated using Microsoft Excel and processed using the Res2Dinv 3.53 program that produce a cross-section of 2D resistivity. The results showed that the weak zone had resistance values of 20-180 Ωm which were suspected to be clay and sand. This weak zone is characterized by a low resistivity value and contrasting a large resistivity value compared to surrounding rocks. This weak zone is detected in almost all measurement trajectories of varying depth and is mostly at a depth of ± 6 m. The weak zone spreads southwest of the research site

Groundwater Potential Using Electrical Resistivity Imaging In Batu Melintang, Jeli, Kelantan

The study is carried out in the northern Kelantan region, specifically at Batu Melintang, Jeli, across a distance of around 20 km2. The study’s main aim is to analyze groundwater potential that can be used for future mining or agricultural propose. Batu Melintang’s lithology consists of slate, phyllite, schist, hornfels, metasiltstone and metasandstone with granitic intrusions. Sungai Pergau and Sungai Tadoh are the major rivers in the area fed by tributary drainages located in the gold mining zones. It is crucial to assess the groundwater potential for future usage as any disruption of the watershed drainage system, could interfere with the primary surface river system which will eventually hinder the importance of Batu Melintang as a gaining popularity geotourism site. This research is conducted by using geological mapping and resistivity surveys. Four survey lines of 200 m are conducted within the study area using the Wenner configuration. Resistivity data is processed using Res2Dinv software and result with RMS error lower than 20% were produced. Both pseudosection of lines L1 and L2 show the occurrence of fresh groundwater (1-100ohm.m) at a depth of 5 meters and below the surface. It also shows the activity of normal faulting that might produce the aquifer. In the cases of LS3 and LS4, potential groundwater found in the continuous low angle aquifer located deeper around 10m to 30m might also be produced by the activity of the thrust fault. The study also found that the best groundwater potential occurred in the zone within the fractured bedrock of metamorphic rock.

English

Vertical electrical sounding (VES) and 2D electrical resistivity tomography (ERT) employing the Schlumberger and Wenner configurations respectively were combined for groundwater exploration in parts of Enugu metropolis. The area is underlain by Enugu Shale and Mamu Formation. A total of twenty (20) VES and four (4) 2D ERT traverses were acquired in the study area. VES and 2D ERT data were processed and interpreted using INTERPEX 1X1D and RES2DINV respectively. Sounding curves shows dominant decrease in resistivity with depth while 2D ERT inverse model shows lateral variation in resistivity of the rock layers with lower resistivity at increasing depth. VES geoelectric layer sections show top sideritic clay - clay/shale sequence. Resistivity curve analysis also shows predominance of Q and K curve types. 2D map of aquifer layer resistivity, thickness and depth were constructed. Aquifer layer resistivity range from 2.00 to 190 ?m, while the thickness range from 10 to 75 m and a depth range of 23 to 150 m. The 2D ERT shows layer resistivity range of 0.1 to 250 ?m. Based on the combination of the two techniques for groundwater exploration in the study area, a water table depth of 18 m with a maximum drill depth of about 100 m was determined. However, it is recommended that the selection of point of drill should be on the low saturated regolith as observed on the 2D ERT sections.   Key words: Aquifer, groundwater, VES, 2D ERT, resistivity.

Subsurface Profile Analysis for Aquifer Layer Identification

Bungaiya village is a village located in Gowa Regency which has volcanic rock lithology with one of the problems faced in volcanic rocks is that the rock porosity is small so that this layer cannot be an aquifer zone. But the water needs needed by the community for agriculture are very large. Geoelectric is a geophysical method that can be used to describe subsurface profiles, especially aquifer layers. The purpose of this study is to interpret using the geoelectric resistivity method, is the Wenner configuration method as many as 2 lines with a length of 470 m and a space of 10 m. The interpretation results on Line 1, there are 3 layers, are volcanic breccia with resistivity values ​​of 85.6 – 2.2013.19 Ωm and depths between 1.2 – 68 m, layer 2 of tuff with resistivity values ​​of 9.82 – 59.68 Ωm, depth of 12 – 76 m and the third layer is a volcanic breccia, resistivity value is 85.6 – 176 Ωm. Line 2 has 2 layers, are the first layer with a depth of 1.2 – 42 m with a resistivity value of 93 – 490.41 Ωm which is a volcanic breccia. The second layer at a depth of 1.2 – 78.8 m with a resistivity value of 30.9 – 77, 67 Ωm is tuff. Layers 1 and 2 show a similar subsurface profile. Based on these results, it can be concluded that the layer that functions as a water-carrying layer is tuff with a resistivity value of 9.82 – 77.67 Ωm.

English

2D electrical resistivity imaging technique has been used to investigate the nature and dimensions of the fracture prone zones in Isu-Awaa, Enugu State, Nigeria. The study area lies within Latitude 06° 14I 0II N to 06° 17I 0II N and Longitudes 007° 23I 0II E to 007° 28I 0II E, with an area extent of about 51 Km2. The area is underlain by three main geological units (Enugu Shale, Owelli Sandstone and Mamu Formation). The study area is topographically undulating with high ridges surrounding the area. 2D electrical resistivity data was acquired with Wenner configuration, employing the roll-along technique to image the subsurface. A total of four (4) number 2D electrical resistivity imaging traverses were carried out. Data was processed and interpreted using RES2DINV. Measured and calculated apparent resistivity pseudo sections were convolved to generate the inverse model resistivity section, which was the diagnostic interpretative model used. Discontinuities in the layering are possible fracture zones. Major discontinuities were observed at distances of 48 and 87, 52.5, 106, 8.0 and 26 m at traverses A, B, C and D respectively. Fracture trend azimuth rose diagram, shows pre-dominant trend to the SE direction with minority to the SW and NW, and relicts to the NE directions. This conforms to the regional lineaments map of Nigeria. The use of 2D electrical resistivity imaging tool has proved useful in the mapping of fracture prone zones in the study area. Key words: Electrical resistivity imaging, fracture lineaments, Rose diagram.

Electrical Imaging Characterization of a Dumpsite on an Abandoned Quarry Site in Abeokuta, South West, Nigeria

A resistivity imaging technique was employed to delineate the degree of leachate plume accumulation and migration for possible groundwater pollution in the subsurface of Saje dumpsite on an abandoned quarry site within the Abeokuta metropolis, Ogun State, Nigeria. A total of twenty-five 2D profiles were mapped, adopting Wenner configuration using Ohmega resistivity meter with electrode spacing ranging from 5-25 m and profile lengths of 100 m. The 2D and 3D inversions of the data were carried out by RES2DINV and RES3DINV software, respectively. The inversions revealed both the lateral and vertical extents of conductive zones, mostly in fractured zones that served as the contaminant pathways. The 3D volumetric visualizations of the subsurface were generated by Voxler 4. The 2D and 3D models depicted regions with low resistivity anomalies ranging from 1.33-70.70 and 4.70-13.20 Ωm to maximum penetrated depths of 13.4 and 21.9 m, respectively. This study identified zones of concentrated pollution to depths that could have reached the water aquifer and indicated contaminants migration pathways that could endanger the groundwater as the dumpsite ages.

Geoelectrical subsurface characterization: A case study of saltwater intrusion in Kudat, Sabah

Saltwater intrusion is one of the primary sources of groundwater contamination, especially near the coastal line, and it is crucial to monitor saltwater intrusion to protect fresh groundwater. Due to the proximity of the coastal line, the area within Kudat Peninsula that was formed by the ophiolite basement, Kudat Formation Chert-Spilite Formation, and alluvium deposit is susceptible to saltwater intrusion. In this study, two survey lines of geoelectrical resistivity and induced polarization imaging survey with a total length of 200 m were carried out. The Wenner configuration was used to characterize the subsurface of the Kudat Peninsula. The interpolation between geoelectrical resistivity and chargeability profiles provided better interpretations of the subsurface environment. The saltwater intrusion zone displays a resistivity value between 0 – 5.0 Ωm and a chargeability value between 0 – 3.0 ms. The results showed that saltwater intrusion was detected at depths as shallow as 1.25 m to 36.90 m and intruded as far as 218.00 m into the mainland, from the coastline.

A multiparametric approach for rejuvenation of the Gaurikund geothermal spring system in the Northwest Himalayan region

The Gaurikund town falls on the way of the famous trekking route to Kedarnath that faced the wrath of the 2013 flood disaster. This fateful event severed more than 5000 casualties, demolished several infrastructures, and shifted the course of Gaurikund spring from its original position. Nevertheless, the Gaurikund geothermal spring system located in the Himalayan Geothermal Belt of the Garhwal region is preeminent for religious beliefs, balneotherapeutic values and a gateway to delve within the geothermal and hydrological characteristics of the area. In this perspective, restoration of Gaurikund geothermal spring system becomes a necessity. A multiparametric approach comprising geospatial, geology, hydrochemistry and geophysics has been used to study and justify these aspects at Gaurikund. The geological studies infer that the geothermal spring gets recharged by the steep, southerly dipping joints in granite gneiss. Subsequently, the deep percolated water heats up due to the high geothermal gradient and then emerge along the Vaikrita Thrust and its sympathetic minor fault-thrust system by advection. Moreover, four spring outlets are inventoried, with discharge varying from 7.46 to 95.54 L/min. The normal emissivity model uses the pre and post-disaster satellite data and generates maximum kinetic temperature images, showing a positive correlation between land surface temperature and spring discharge. Two-dimensional Electrical Resistivity Tomography (Schlumberger, Wenner and Gradient configurations) survey revealed two low resistivity zones proximal to the geothermal spring on the right bank of the Mandakini river. The engineering interventions carried out by bank protection and construction of small gully plugs in the catchment area is recommended along Gaurikund-Sonprayag section on the right bank of Mandakini river.

COMBINED TECHNIQUE SOIL SOUNDING IN THE FRAMEWORK OF MONITORING THE CONDITION OF THE GROUNDING SYSTEM

The result of vertical electrical sounding is the determined geoelectrical structure of the soil. The soil probing procedure is regulated in a number of national and international standards for testing grounding systems. The use of a traditional four-electrode symmetrical Wenner array configuration allows conducting research to a depth of up to 1/3 of the distance between current electrodes, which is not enough for the correct calculation of the parameters of the grounding system. An alternative can be the use of a Schlumberger array configuration. It is shown that the features of this array configuration, when used as part of the testing of grounding systems, become disadvantages: it is sensitive to local inclusions and vertical heterogeneity, necessary the complex formulas for interpretation, the absence of a direct relationship between the separation of electrodes and the probing depth, and therefore the impossibility of building universal palettes of interpretation. Therefore, there was a need to create a technique of probing the soil within the framework of monitoring the state of the grounding system with a greater depth. The work justified the need for such development. Based on the analysis, the requirements for the soil probing procedure were formed, which should correspond to the methodology of electromagnetic diagnostics of grounding systems. It is shown that one of the main requirements is the presentation of sounding results in the form of a multilayer geoelectrical structure with plane-parallel horizontal separation boundaries. A combined method of performing soil sounding is proposed, which is based on the step-by-step use of Wenner and Schlumberger array configurations, which made it possible to combine the advantages and reduce the effects of the disadvantages of these installations within the framework of monitoring the state of the grounding. The proposed combined technique of soil sounding allows to increase the depth of probing from 1/3 of the distance of the current electrodes to 1/2 without the involvement of additional measuring devices, interpretation software and electrical personnel. At the same time, the duration of procedure for an operating substation will be 30-90 minutes, which will not increase the total duration of electromagnetic diagnostics of grounding system.

Correlation of 2D Electrical Resistivity and Self-Potential Methods for the Assessment of the Integrity of Goronyo Dam NW Nigeria

Abstract In this research, combined 2D electrical resistivity and self-potential (SP) methods were employed to locate anomalous electrical conductivity around the Goronyo dam in order to determine the condition of the embankment of the earth dam. The data were taken with the reference to resistivity and SP values using Wenner configuration. The results obtained from these techniques shows that the area was underlain by four stratigraphic layers, namely; clayey sand, wet sandy clay, laterite and partially weathered basement complex rock as compared with the resistivities of common rocks and borehole lithology of the area. The low SP (< 200 mV)/high resistivity zones in the overburden of profiles P1, P2 and P3 shows the presence of partially weathered basement complex rocks which was probably due to compactness and dryness around the dam. However, the zones of high SP (≥ 200 mV)/low apparent resistivity regions (z1 and z2) of profiles P1 (2 Ωm to 27 Ωm), P2 (3 Ωm to 25 Ωm) and P3 (3 Ωm to 14 Ωm) have revealed the weak zones associated with wet sandy soil. Results obtained from 2D electrical resistivity (z1) technique have correlated well with the results of SP sections (z2). These regions of weak zones occupied the x-distance along the profiles; P1/or S2 (120 m to 200 m and 250 m to 400 m), P2/or S2 (1 m to 156 m and 192 m to 400 m) and P3/or S3 (48 m to 400 m) with their corresponding depth y, ranging from 23 m to 30 m, 26 m to 30 m and 23 m to 30 m. Keywords: 2D Electrical Resistivity Tomography (ERT), Self-Potential (SP), Dam, Subsurface, Seepage, Condition

Effectiveness of Laboratory Physical Modeling in Acquiring the Response of Time Domain Induced Polarization (TDIP)

Induced Polarization (IP) is one of the Geophysical methods that utilize the polarization properties of the rocks for metallic mineral exploration. The problems are how to distinguish the metallic minerals deposit based on the chargeability. The physical modeling of IP is used to study the behavior of TDIP response. The study of a simple mathematical model is carried out to obtain the theoretical curves which are presented as the subsurface parameter. These curves are used as a reference to assess the result of physical modeling. The laboratory physical modeling uses a tank model with a size of (200x100x70) cm3, with a block as a target and water as a host medium. The results show laboratory physical modeling which has been made is quietly good. The approximate position and geometry of the target can be identified. The resistivity inversion modeling is sensitive to recognizing the geometry and position, while the chargeability inversion is on the distribution of metallic minerals. The quantitative correlation between chargeability and iron-ore content is obtained by Dipole-dipole and Wenner configuration. Both are connected exponentially, with a different exponential constant for different block targets.

Combined ERT and GPR Data for Subsurface Characterization of Weathered Hilly Slope: A Case Study in Zhejiang Province, Southeast China

Rain-triggered landslides frequently threaten public safety, infrastructure, and the economy during typhoon seasons in Zhejiang Province. Landslides are complex structural systems, and the subsurface features play a significant role in their stability. Their early identification and the evaluation of potential danger in terms of the rupture surface and unstable body are essential for geohazard prevention and protection. However, the information about the subsurface acquired by conventional exploration approaches is generally limited to sparse data. This paper describes a joint application of ground-penetrating radar (GPR) with a 100 MHz antenna and the electrical resistivity tomography (ERT) method with the Wenner configuration to identify the stratum structure and delineate the potentially unstable body of a clay-rich slope, the results of which were further verified using borehole data and field observation. The acquired results from the GPR and ERT surveys, consistent with each other, indicate two stratigraphic layers comprising silty clay and silty mudstone. Moreover, the potential rupture zone very likely exists in the highly weathered mudstone in the depth range of 3–7 m, and the average depth is 5 m. In addition, the thickness of the unstable mass is greater on the east and crest parts of the slope. Conclusively, the optimum combination of ERT and GPR is reliable for conducting rapid and effective delineation of subsurface characteristics of clayey slopes for risk assessment and mitigation during the typhoon season.

IDENTIFIKASI AIR TANAH MENGGUNAKAN METODE GEOLISTRIK DI KECAMATAN POMALAA KABUPATEN KOLAKA PROPINSI SULAWESI TENGGARA

ABSTRACTThis research is motivated by development and population growth continues to increase from day to day. The impact of population growth is the increase in residential land. The increase in residential land is sometimes not accompanied by the provision of clean water by PDAM, so that people use dug wells or drilled wells. In the Kolaka area, especially the Kolaka District area, which is the research location, it is also a location that is difficult to find fresh water, so the geoelectric method plays a very important role in efforts to determine which locations contain fresh water. This research uses resistivity geoelectric method with Wenner and Schlumberger configuration. Processing data using Res2Dinv to map 2D isoresistivity. The well depth data was processed using Microsoft Excel, Surfer 10.2 application and ArcGIS to create a groundwater network map. The measurement trajectory uses a space of 7 meters, 20 meters and 40 meters. The results of the study obtained different resistivity values for each rock. The resistivity variation obtained starts from 0.453 – 13,988 m. Groundwater resistivity values are in the range of resistivity values of 0.453 – 33.3 m. The lithology of the aquifers in the study area is alluvial and sandstone. In the research location, groundwater is generally found at a depth of more than 5 meters

Potential Aquifer Exploration using Electrical Resistivity Imaging at Rumbio Jaya, Kampar, Riau

Groundwater sustainability has become a serious issue as a water resource needed by society. Therefore, electrical Resistivity Imaging was carried out at Rumbio Jaya, Kampar, and Riau to study groundwater aquifer's electrical characteristics. The equipment used is a Geocis resistivity meter with (32) multi-electrodes alignment. Wenner configuration electrode was applied in this survey. The 2-D Electrical Resistivity inversion results indicate there are three resistivity zones; (1) Low resistivity value (0.0093 – 4.84 Ωm) representing conductive clay; (2) intermediate resistivity value (1.07 – 171 Ωm) indicate as potential aquifer layer; and (3) a high resistivity value (61 – 4000 Ωm) occupying as bolder of rock. All the zones have different thicknesses and depths, but mostly clay layers dan boulders are shown as lenses in the aquifer of the study area. Meanwhile, the aquifer layer is found easily at a depth of 1 meter up to 30 meters.

Geophysical and Hydrochemical Studies to Map Saltwater Infiltration into Freshwater aquifers: A case study of Ikoyi, Lagos State, Nigeria

A total of three electrical imaging lines were measured using the Wenner configuration. And a total of fifteen VES was carried out within the area of investigation and six water samples was collected. The results were presented as profiles, model sections, inverted sections and tables. Interpretations of these results involve both qualitative and quantitative deductions from 1D and 2D geoelectric models and laboratory analysis for the water analysis. The VES data were processed by partial curve matching to generate the 1st order geoelectric parameters and inverted in 1D using the WinResist. The 2D resistivity data were processed by inversion using the DIPROFWIN to generate the 2D resistivity section across each traverse while the water samples were taken to the laboratory for comprehensive analysis. The 2D resistivity structures reveal the lateral and the vertical subsurface information with resistivity values ranging from 0.130 to 4741 Ωm. The resistivity values are representative of the clay, clay (saline), clayey sand (saline), clayey sand and sand. From the quantitative interpretation five to six distinct layers were identified. The layers are: topsoil, clayey sand, clay, saline clayey sand, saline clay and sand. The resistivity of the topsoil varies from 38.2 Ωm to 155.3 Ohm-m. The resistivity of the sand varies from 100.8 Ωm to 115.8 Ωm. The resistivity of clayey sand varies from 56.6 Ωm to 90.1 Ωm. The resistivity of clay varies from 12.7 Ωm to 41.2 Ωm. The resistivity of the saline layer (saline clayey sand/clay) varies from 2.1 Ωm to 51.2 Ωm. The depth of saline clay interface varies from 25.7 m to 72.6 m. The depth to the saline clayey sand interface varies from 25.7 - 72.6 m. The chemical analysis of water samples showed that the pH varies from 7.05 to 8.42, total dissolved solids vary from 1786 to 2116 mg/L and electrical conductivity varies from 2106 to 2656 µS/cm. The anions and cation concentrations such as Ca2+, Mg2+, Na+, K+, Cl- and HCO3- ranges from 158 to 185 mg/L, 36 to 48 mg/L, 222 to 287 mg/L, 3.2 to 3.8 mg/L, 10.86 to 20.87 mg/L and 2.33 to 3.88 mg/L respectively. The ratio of Cl/HCO3- ion ranges from 4.05 to 7.67. The interpreted results show saline water intrusion where they occur in different part of the area investigated. The results showed the effectiveness and usefulness of electrical resistivity method in mapping saline water intrusion problem in coastal areas. However, it is necessary to carry out integrated geophysical surveys involving electrical resistivity and induced polarization methods prior to drilling in the study area.

Integrated resistivity study on the effect of dumpsite leachate on groundwater at Ezeani-Obimo, Nsukka, Enugu state Nigeria

The effect of dumpsite leachate on groundwater at the Ezeani-Obimo community was performed by employing Schlumberger and Wenner configurations for four vertical electrical sounding (VES) and four electrical resistivity tomography (ERT). Four geoelectric layers were obtained and characterized by KH, AK, KH, and QH curve types. The first layer, second and third layer has resistivity values ranging from 21.2 to 7026.0 with thickness and a depth ranging from 0·5-31.6 m. The fourth layer has resistivity values ranging from 105.9 to 3355.4 with undefined thickness and depth values harboring all the aquifer units in the study area. Aquifer resistivity and thickness values vary from 105.9 to 3355.4 and 6.6 to 27.1 m while aquifer conductivity ranges from 0·0003 to 0·0094 increasing towards the E-W direction. The longitudinal conductance and transverse resistance values vary from 0.0024 to 0.0623 and 698.94 to <br /> 27178.7 respectively. 2D ERT profiles show low resistivity in the eastern direction and a lateral spread of low resistivity value indicates that leachate flow is moving away gradually from the dumpsite to its outside environment. This study revealed that the layers harboring the aquifer in the area are significantly affected as a result of dumpsite leachate that accumulates on the surface. This result is beneficial for waste managers to take mitigation measures to prevent the risk of total contamination of the groundwater in the area in the nearest future.

APPLICATION OF STATISTICAL ANALYSIS ON THE DYNAMICS OF FOUNDATION STUDIES USING GEOPHYSICAL PARAMETERS IN A TYPICAL SEDIMENTARY ENVIRONMENT, SOUTH SOUTH NIGERIA

A statistic is found useful in many applications of science where data and analysis are used for illustration and description for better understanding and justification of the data sets. Therefore in an attempt to achieve a better understanding and illustration of the dynamics of foundation integrity and vulnerability of failure, which often remain a major challenge to mankind, especially in Nigeria where foundation failures remain a major concern to both the Government and citizen. In this present study, a statistical approach was carried out on the Geophysical parameters in Issele-Mkitim area, South South Nigeria, to evaluate the dynamic factors that affect foundation integrity and vulnerability of subsurface lithologies. Very Low Frequency Electromagnetic (VLF-EM), Magnetic, and Electrical Resistivity Methods were used in this study. The Electrical Resistivity Method involved Lateral Horizontal Profiling (LRP) utilizing Wenner configuration. The three (3) methods correlated in terms of statistical prediction and understanding of the geologic dynamics natured associated with foundation failure and integrity. It was deduced that profiles one to six has high tendency of weak geological material which can easily lead to subsidence if any engineering construction is erected on it. However, proper consideration must be put in place to avoid future differential settlements. All the methods give useful information about the dynamics of the geological trends from the preliminary data analysis and interpretations, and a better understanding of the geodynamics nature of the soil as well as the region of a weak and competent zone in terms of engineering constructions.

Resistivity Method for Characterising Subsurface Layers of Coastal Areas In South Sulawesi, Indonesia

The data presented in this paper are related to the characterization of a subsurface layer of coastal area in South Sulawesi. This research will fill the gap in the resistivity method study which is this method not yet use in the coastlines area, especially area influenced by seawater and coastal condition impact like South Sulawesi. The method used in this study is the method of resistivity Wenner configuration by taking the data 1-2 lines each region with lengths 45 m, 75 m, 105 m, and 120 m respectively. Data processing using non-linear least square optimization with that of the 2D inversion software Res2Dinv. The results show that the area is underlain by two layers of lithologic sections. In some sections interpreted by sandy layer, clay, sandstone, alluvium, sandy in seawater and metal minerals. From the analysis of the layers, all regions show the resistivity minimum is 0.00849 Ωm and 8.04 Ωm maximum resistivity. The result of this research can give n insight to study the large coastal area subsurface.