Induced Polarization Method Research Articles

Identification of Alteration-Mineralization in Skarn Deposit System based on Time-Domain Induced Polarization Method Approach in Kasihan Area, Pacitan, East Java

This research was conducted in Kasihan, Pacitan, East Java with the aim of knowing the alteration zone and ore mineralization from mineral sediment systems based on the conductivity and resistivity of subsurface rocks in the study area. A geophysical method is needed to map area area area of the prospect of mineral deposits as well as mathematical models in the area research. One of the geophysical methods used in studies of mineral sediment cases is Time Domain Induced Polarization (TDIP). Measurement of Time Domain Induced Polarization method done with configuration dipole-dipole which is arranged relatively straight northeast-southwest as much 2 tracks, with each track having the length of 260 m with an initial space of 20 m electrodes. Targets of the TDIP Method can describe subsurface conditions as far as 48 m. The position of mineralization in skarn deposits in the Time Domain Induced Polarization method at a depth of 25 m below the surface topography shown by high resistivity values >2000 Ωm and >500 msec chargeability in dacite and limestone

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.

GEOPHYSICAL EXPLORATIONS BY RESISTIVITY AND INDUCED POLARIZATION METHODS FOR THE COPPER DEPOSIT, SOUTH KHORASAN, IRAN

Link for citation: Adel Shirazy, Ardeshir Hezarkhani, Aref Shirazi, Timkin T.V., Voroshilov V.G. Geophysical explorations by resistivity and induced polarization methods for the copper deposit, South Khorasan, Iran. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2022, vol. 333, no. 3, рр. 99-110. In Rus
 The relevance. These are the first geophysics studies in the Mesgaran exploration area. Based on geological studies in the mineral zone, copper mineralization was proven. The mineralization type in this area was identified as Cyprus-type massive sulfide. The complexity of the geological structure determines the need to use geophysical research and forecasting methods for planning mining and drilling operations. The main aim of this study is the application of geophysical methods in the search for mineral deposits and modeling of the geological environment. Object: Mesgaran exploration area, South Khorasan province, Iran. Methods. In order to obtain more subsurface information, geophysical methods IP and Rs were used. Five profiles were designed and implemented for geoelectric surveys. Overall, five profiles (P1 to P5) were read as dipole-dipole arrays with 784 points. The profiles were taken east-west and north-south along parallel to the mineralization zones. The dipole-dipole array is designed with the parameters AB=MN=20 m, jump=20 m and up to 6 jumps for MN. Results. In general, four types of anomalies were identified in these investigations. Which to some extent revealed the association of anomalies with the types of rocks and mineralization of the study area: 1) anomalies with low electrical resistivity, as well as low polarity, often correspond to quaternary alluvial deposits; 2) abnormalities with high electrical resistance, and low polarity, which are consistent with limestone’s and are often superficial; 3) anomalies with high polarity and high resistance, which in the south of the profiles form altitude and correspond to the agglomerates; 4) anomalies with high polarity and higher relative resistance are associated with igneous masses, which are often composed of andesitic-basaltic rocks. Based on the position of the identified anomalies in the 5 profiles, the optimal location of the drills was determined.

Geothermal Resource Exploration in Magmatic Rock Areas Using a Comprehensive Geophysical Method

Geothermal resources have significant development and usage potential. It is critical to conduct geological investigation of geothermal resources prior to mining, so as to deepen our knowledge and comprehension of geothermal resources. Ground water is heated by magmatic rocks and geothermal resources can be created in magmatic rock areas. However, their communication is weak, and the depth of burial is typically great. It is difficult for traditional geophysical methods, such as induced polarization method, to achieve useful exploration depths, and they have low accuracy. In this article, a comprehensive geophysical method, based on the controlled source audio-frequency magnetotelluric method (CSAMT) and transient electromagnetic method (TEM), is applied to geothermal exploration in a magmatic rock area. This method compensates for the shortcomings of a single method and achieves a good exploration effect, thereby providing a reliable geological foundation for further development and utilization of geothermal resources.

Identification of Iron Ore Deposit in Sub-Surface Using Electrical Resistivity and Induced Polarization Methods in Nangabulik, Central Kalimantan

Nangabulik, Lamandau Regency was one of the territories in Central Borneo that has potential for iron ore resources. A lot of geophysics methods can be used for exploration, among electrical resistivity and induced polarization methods. Then research is conducted to analyze the distribution model of resistivity and chargeability values in the subsurface, interpreting the location of iron ore based on resistivity and chargeability parameters, investigating alignment zone of iron ore deposit, and analyze the estimated total of iron ore resource. The configuration used is Wenner Alpha with 4 passes, each of which length is 235 m. Based on the 2D inversion result, resistivity and chargeability values were 21,15 – 96.153,51 Ωm and chargeability 23,6 – 542,58 ms. The iron ore deposit is to be found at GL-01, GL-02, and GL-04 tracks marked by resistivity value 614,22 – 5.803,90 Ωm and contrast in chargeability value around 212,32 – 542,58 ms. Large resistivity value due to porous between pebble–boulder iron ore fragments shape with pyroclastic rock grains filled the air. Based on the 3D model there was not found alignment zone of iron ore deposit at the research region. The total estimated deposit iron ore resource in the research region, at area ± 6 hectares is 41.036 tons.

Dual-Frequency Induction Polarization Electric Field Focusing Based on Intelligent Algorithm for Coal Mine Electric Exploration

As the most important and dangerous front-end production link, coal mining operations will inevitably face geological disasters such as water inrush, rock burst, collapse, and fire, posing a great threat to the life and safety of miners. Among the five major geological disasters (gas, dust, water, fire, roof) in coal mines, the threat of flooding is very serious and it is one of the main disasters in coal mines. The research and development of dual-frequency excitation technology and its application in coal mine exploration have realized the elimination of potential safety hazards, improved the work efficiency and safety factor of prospectors, and realized the automated operation of the exploration process. This article explores the electric field of the intelligent algorithm’s focused dual-frequency induced polarization method in coal mine electrical exploration, and summarizes some of the advantages of the intelligent algorithm’s focused dual-frequency induced polarization method in coal mine surveying on related materials, and then conducts related experiment, through the experiment of focusing on the dual-frequency IP method in the coal mine survey, obtained the result, in the abnormal point detection experiment, the change trend of the two curves is the same, the increase is more obvious at 1.3-1.5m, and at 1.5m When reaching the limit value, when it exceeds 1.5m, it starts to fall. It shows that when there is a water-bearing anomalous body directly in front of the tunneling section, the measurement results of the two survey lines are roughly the same. Compared with the no anomaly body, the apparent resistivity and the apparent amplitude frequency both change significantly, and reach the extreme in a certain direction. However, the actual anomalous body is located 1.0m directly in front of the tunneling section, which means that the actual position of the anomaly cannot be determined based on the apparent resistivity and the extreme point position of the apparent amplitude frequency.

Integration of ERT, IP and SP Methods in Hard Rock Engineering

Investigation of a hard rock site for the development of engineered structures mainly depends on the delineation of weathered and unweathered rock, and the fractures/faults. Traditionally, borehole tests are used in such investigations. However, such approaches are expensive and time-consuming, require more equipment, cannot be conducted in steep topographic areas, and provide low coverage of the area with point measurements only. Conversely, geophysical methods are non-invasive, economical, and provide large coverage of an area through both vertical and lateral imaging of the subsurface. The geophysical method, electrical resistivity tomography (ERT), can reduce a significant number of expensive drilling tests in geotechnical investigations. However, a geophysical method alone may provide ambiguity in the interpretation of the subsurface, such as electrical resistivity cannot differentiate between water and clay content. Such uncertainty can be improved by the integration of ERT with induced polarization (IP). Similarly, self-potential (SP) can be integrated with other geophysical methods to delineate the groundwater flow. In this contribution, we integrated three geophysical methods (ERT, IP and SP) to delineate the weathered and unweathered rock including the weathered/unweathered transition zone, to detect the fractures/faults, and to map the groundwater flow. Based on ERT, IP and SP results, we develop a geophysical conceptual site model which can be used by site engineers to interpret/implement the findings for build-out. Our approach fills the gaps between the well data and geological model and suggests the most suitable places for the development of engineered structures in the hard rock terrains.

Integration of induced polarization, resistivity, and magnetic data of IOA occurrences in Ararenda, western of the Santa Quiteria magmatic arc, Ceará Brazil

The Neoproterozoic Santa-Quitéria Magmatic Arc (SQMA) hosts significant IOA occurrences that were recently documented in their geological, petrographic, geochemical, and geochronological aspects. To advance the understanding of the geologic framework and metallogenetic potential beneath the SQMA, we used an integrated geophysical approach. In this context, this study is the first geophysical evaluation of these occurrences and provides valuable insights into the ore mineralization of this under-researched region. Seven profiles (E-W direction) were acquired using magnetic, resistivity, and induced polarization methods. The results allowed us to integrate the geological map information with the geophysical anomalies at the subsurface. According to the resistivity and IP inversions there are resistive and chargeable bodies at depths ranging from the surface to up to 180 m, and it is possible to associate the IP anomalies in shallow depths to deep magnetic 3D anomalies modeled. Most 3D magnetic anomalies are located on or very close to the IOA occurrences identified on the surface. The positive anomalies on the IP-chargeability map are related with the sites of alterations, shears, and contact zones. In addition, based on geological mapping, there is a correlation between high chargeability values and high magnetic values with iron formations (iron ore). In contrast, the correlation between high chargeability and low magnetic values indicates metal sulfides (including copper). The results presented here is a start point to further exploration work for this mineral system and we can suggest the future development of more dense geophysical data to better characterize it. An exploratory drilling holes campaign should be used in a second stage as a basis for the 3D geological model of this area. These two approaches will be crucial to improve the mineral knowledge of the SQMA.

The Forward Modeling for Surface-borehole Observation Responses of Polarized Target

Surface-hole induced polarization method is a typical deep resource exploration technology, which plays an important role in the mineral survey. The traditional surface-hole induced polarization method is mainly to observe a single polarized secondary field. At present, the time spectrum observation of polarization fields is becoming more and more popular, which greatly enriches the interpretation technology of induced polarization data. In this work, the time spectrum induced polarization method is expounded, the decay polarization fields were numerical calculated and analyzed for the typical 2-dimensional geoelectric model. The results show that for a single polarized target, the time spectrum obtained from different azimuth observation responses are basically the same, which can effectively reflect the time-varying characteristics of the polarized fields. The observation responses of polarized target at different depths can still reflect the time spectrum of decay fields. The main change of the observed response of the polarized target closer to the borehole is the response amplitude. The conclusions and simulations of this study can provide working mode for relevant research and reference for similar work.

Issues of developing receiving equipment for the passive method of induced polarization

The article deals with the design of receiving equipment for the passive method of induced polarization (IP). It is shown that the best option for recording this kind of signals is a circuit with an input analogue part and amplification of 50-100 times, as well as an input gain of at least 3 MΩ and a digital part based on a modern twenty-four-bit analogue-to-digital converter (ADC). In this case, it is preferable to use one ADC per channel without multiplexing, for better suppression of inter-channel interference. Signal processing is performed using modern microcontrollers based on the Cortex M4 core, and then the data is transmitted via Bluetooth to a laptop or tablet, where visualization and post-processing is carried out. Thus, the proposed scheme for the implementation of the receiving equipment meets all the requirements for the receiving equipment for the passive IP method, and can be introduced into the practice of field work.

SOME PROBLEMS OF ELECTRICAL GEOPHYSICAL PROSPECTING METHODS USED FOR EXPLORATION OF ORE DEPOSITS

Electrical geophysical prospecting methods are widely used at different stages of geological exploration. In the last two decades, new computer technologies and satellite navigation systems were successfully introduced in the geophysical industry. As a result, exploration technologies have improved, and new geophysical methods have been developed, such as electrical resistivity tomography (ERT) and spectral induced polarization (SIP) methods. An important role in ore geophysics is played by magnetotelluric (MT) methods. In this article, we focus on the issues of methodology and interpretation of electrical prospecting data for solving ore exploration problems. Special attention is paid to the induced polarization (IP) method that is most widely used in mineral exploration and mining industry as one of the most important and most dynamically developing techniques of ore geophysics. In addition, the issues of correct choices of survey scales and the use of automatic 2D and 3D inversion programs are considered.

Integrating Ground Penetrating Radar, Induced Polarization and Aerial Photograph to Analyze Land Subsidence in Borehole Mining Operation Area: A Case Study from South Bangka Island

The remaining alluvial tin reserves around large ex-mining area can be an opportunity to optimize the potential reserves using a small-scale mining system. One of the latest breakthroughs in the mining system for the remaining alluvial tin reserves on land is the borehole mining (BHM) method. However, mining operations using BHM have several environmental impacts especially related to its former holes. This study aims to identify the changes in geometry of the former holes both on the surface and below the surface through direct field observations and measurements using geophysical methods. The study site is in the large ex-mining area of Air Nudur Block in South Bangka Regency, Bangka Belitung Islands Province. The geophysical methods used to identify the changes in the geometry of the BHM holes are GPR (ground penetrating radar) and IP (induced polarization). The GPR method has high resolution subsurface visual capabilities at shallow depths and this method can distinguish between stable and unstable layers. The IP method is used to determine the overburden layer and the condition of the alluvial layer where some of it has become a hole. These two methods will mutually reinforce in interpreting the change in the geometry of the BHM holes. Changes in hole diameter and depth were measured directly in the field within 2 (two) months from the completion of mining operations using the BHM method followed by the periodic topographic measurements using UAV (unmanned aerial vehicle). The results of observations on changes in the elevation of the ground surface around the former BHM hole indicated that the land level subsided by about 1 m. Meanwhile, the results of GPR data processing showed changes in the hole geometry with the hummocky radargram pattern into chaotic. Interpretation of IP data processing shows resistivity values of 250 - 1700 ohm.m and chargeability of 15 - 25 ms in the disturbed alluvial layer around the former BHM holes.

Study on the effect of ion invasion on compressive strength, resistivity and polarizability of concrete

The structural safety of concrete has been attached great importance, especially in saline-alkali area. In order to better study the changes of physical parameters of concrete after corrosion in saline-alkali area, the soil quality in saline-alkali area was investigated and sampled to analyze the main ionic components of concrete corrosion environment. According to the corrosion ionic components, the concrete model was made by mixing carbonate and sulfate solutions with different concentrations. Resistivity method and induced polarization method were used to measure the resistivity and polarizability characterization of the model within the curing period (28d), and the compressive strength of the concrete model during the curing period was tested to study the correlation between the resistivity, polarizability and compressive strength of the concrete model. The results show that the resistivity, polarizability and compressive strength of concrete are closely related to the type and concentration of ions. There is a corresponding relationship between the polarizability and the bearing capacity of concrete test blocks mixed with the same solution. The larger the polarizability, the weaker the bearing capacity. There is no strong correlation between resistivity and bearing capacity. Polarizability data can reflect both ion invasion and strength change of concrete.

Analysis of Geomagnetic and Geoelectric Data to Identify the Potential of Gold Deposits (Case Study: Randu Kuning, Wonogiri, Central Java)

The gold deposit of the low sulfidation epithermal system at the Randu Kuning prospect, Wonogiri, Central Java is the effect of magmatism during the Oligocene due to microdiorite intrusion. The magmatism causes a mineralization process that fills the fractures in the rock. The mineralized of ores that formed in the study area are pyrite, chalcopyrite, sphalerite, galena, electrum and native gold, magnetite and hematite. The appropriate geophysical method to this case study is using the geomagnetic and geoelectric Induced Polarization method. The application of the geomagnetic method aims to delineate mineralized zones and geological structures as channel way for hydrothermal fluids. The results of the geomagnetic method are in the form of a map of Total Magnetic Intensity carried out by filters such as Reduce to Pole (RTP) - High pass (HP) and Horizontal Gradient (HG). The west side of RTP - HP anomaly shows a low response of -4.9 to -0.8 nT due to intensely mineralized rock and the presence of fractures. The comparison between RTP - HP anomaly and HG anomaly shows the suitability due to intense mineralization which reduces the fault anomaly. A high HG value area of 0.001-0.0017 nT/m is interpreted as a mineralized fault. This can be seen from the alteration map which shows the continuity of veins from measurements in the field. The application of the geoelectric Induced Polarization method aims to identify associated mineral of gold vertically subsurface. Based on the results of geoelectric Induced Polarization data shows that there are chalcopyrite minerals at a depth of 20-30 m with a chargeability of 4-9 msec which is located in intrusion of igneous rock with a resistivity >200 Ωm. Based on geomagnetic geoelectric data, it can identify potential gold deposits in the Randu Kuning area, Wonogiri, Central Java.

Investigating Peat Soil Stratigraphy and Marine Clay Formation Using the Geophysical Method in Padas Valley, Northern Borneo

A geophysical survey including electrical resistivity tomography (ERT), induced polarization (IP), and seismic refraction (SR) was carried out to estimate peatland thickness in Beaufort District, Eastern Malaysia. Peatlands are important natural carbon storage and play a key role in the global carbon cycle. The ERT and IP studies were performed along three profiles over different peat thicknesses using Schlumberger configuration. The SR survey was carried out using vertical geophones along the same profiles. The peat soil material was characterized by low seismic velocity and high resistivity. Our results show that ERT and IP methods were able to clearly detect the interface between the peat soil and marine clay underneath. These layers differ greatly in geoelectrical characteristics showing clear contrast, thus enabling the delineation of peat soil stratigraphy, while the SR image obtained was not able to determine the base of the peat soil layer as the stiffness difference on the transition layer was very small. Overall, it was concluded that the ERT and IP method offer a useful alternative in delineating the peat soil stratigraphy. The combined application of ERT and IP method with the conventional boring method meets the demand for large volume peat stratigraphy mapping, which, moreover, has various ecological conditions and undulating strata.

Application of magnetic and induced polarization method for delineating gold-bearing vein zones at Cibaliung, Pandeglang Regency, Banten

Magmatic processes occurred during the Miocene period caused the formation of epithermal gold deposits in Cibaliung area. The deposit has previously been investigated through geological surveys which basically only covers the surface aspect, so in this study a subsurface analysis was carried out through magnetic and IP surveys to determine the distribution and continuity of the gold deposits. The magnetic survey was conducted over an area of about 3 km2 with sampling interval 20 m east and 100 m north. The magnetic data were processed using Oasis Montaj with magnetic intensity map as an output, which was then interpreted to determine the presence of structures and magnetite destruction zones as mineralization clues. The IP survey was conducted on 20 east-west oriented lines with length of about 1.2 km. The electrode configuration used is Wenner with 25 m spacing. IP data were processed using RES2DINV software to eliminate bad datum points and invert the apparent chargeability values into the true ones. IP data are then interpreted to clearly determine the position, direction, and distribution of gold mineralization body by detecting the presence of sulfide minerals as ligands carrying gold. Magnetic data analysis shows that gold mineralization tends to occur at low magnetic anomaly, ranging from 37 nT to 240 nT and generally associated with northwest-oriented structures. The mineralization zone is found in four main vein zones with resistivity and chargeability values < 51 Ωm and > 50 ms.

Bedrock architecture, soil texture, and hyporheic zone characterization combining electrical resistivity and induced polarization imaging

The shallow (<15 m depth) subsurface environment of a short reach along a bedrock stream was investigated with electrical resistivity and induced polarization (IP) to map details of bedrock and soil sediments. The bedrock is mostly comprised of limestone, and is generally resistive compared to the overlying soil. The soil-bedrock interface was determined through a trial and error approach using a sharp boundary feature in the inversion model. The inferred bedrock surface determined from the inversions exhibited undulating patterns with troughs and ridges. A near continuous trough ran alongside the stream within the floodplain, and is suggestive of a paleochannel among other interpretations of this feature. The structure of the electrical resistivity above the bedrock showed small-scale elongated features. The chargeability from the IP method showed larger scale features. High values of chargeability were associated with the sediments in the floodplain, and low values were associated with bedrock, stream, and soil on the elevated banks above the stream. If the chargeability is associated with membrane polarization characteristic of clayey soils, then IP seems to highlight the mere existence of clay, while the resistivity may be more discernable of the relative proportion of clay. Vegetation differences may also explain the chargeability distribution, where parts of the survey with high chargeability had dense pine with no understory making the soils more organically rich.

Numerical modeling of anisotropy paradoxes in direct current resistivity and time-domain induced polarization methods

Numerical modeling of anisotropy paradoxes in direct current resistivity and time-domain induced polarization methods

The forward modeling for surface-borehole observation responses of polarized sphere in uniform electric field

Surface-borehole induced polarization method is a common geophysical method in metal exploration. The forward calculation results of the borehole observation responses can provide reference and support for practical work. In particular, the forward results of spherical polarized target can be equivalent to massive ore body or karst caves and other low-resistivity anomalies. In this paper, the forward simulation of borehole induced polarization responses is carried out by using the electric dipole model equivalent spherical polarized body. The results show that the polarization degree of the excitation source at different positions is different, and the closer the proximity is, the stronger the secondary field anomaly is. Borehole observation has advantages for the identification of deep ore bodies. Under the same offset condition, the closer the distance from the borehole is, the stronger the responses will be. The results of this paper can provide reference and basis for relevant research work.

Characterization of Tailings Dams by Electrical Geophysical Methods (ERT, IP): Federico Mine (La Carolina, Southeastern Spain)

This work analyzed the effectiveness of two electrical geophysical methods in characte-rizing tailings dams. A large flotation cell used for sludge thickening in the concentration plant of the Federico Mine (closed in 1985) within the old mining district of La Carolina (southeastern Spain) was selected for this research. In addition to the direct information provided by the geology of the study area and the surface exposure of the waste deposits, information regarding the construction of this mining structure was available, which helped in the interpretations of the geophysical survey data. In this study, two geophysical surveying methods were used simultaneously: Electrical resistivity tomography (ERT) and induced polarization (IP). Six profiles were acquired, processed, and interpreted. The length of the profiles allowed the obtaining of data reaching maximum investigation depths ranging between 7 and 65 m. These profiles provided information for a detailed analysis of the internal characteristics of the deposited materials. The lateral and vertical observed variations are linked to different degrees of moisture content. The study also defines the geometry of the top of the bedrock and the tectonics that affect the pouring/dumping hole. Old flotation sludge has resistivity values that range between 1 and 100 Ωm (i.e., wet waste 1–30 Ωm, dry waste 30–100 Ωm), while phyllites in the rocky substrate have resistivities larger than 200 Ωm and can even reach va-lues greater than 1000 Ωm. Between the waste and unaltered phyllites, there is a supergene alteration zone (weathering) with resistivity values between 100 and 200 Ωm. The IP method was used to detect the presence of metals in the accumulated waste in the pond by analyzing the presence of large chargeability anomalies. Anomalies were detected in four of the profiles, which ranged from low (i.e., between 0 and 8 mV/V) to medium (i.e., between 8 and 18 mV/V) and high values (i.e., 18 and &gt;30 mV/V).