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Induced Polarization (IP) is one of the Geophysical methods that utilize the polarization properties of the rocks. This method is widely used in metallic mineral exploration. In this method, it is known a specific method that called as Time Domain Induced Polarization (TDIP). The physical modeling of IP is used to study the behavior of TDIP response to the subsurface parameters. The fieldscale physical modeling is the development of the laboratory physical model. This modeling is realized by burying objects with a specific geometry that have contrasting physical parameter to host medium in the area that is not too extensive. Soil is used as host medium, sphere and block object which has variation in metallic mineral content as a target. The extreme targets was also made to evaluate the electrodes measurements. Data acquisitions are using the Dipole-dipole and Wenner configurations. The purpose of this study is obtaining the relations between TDIP response to changes of metallic minerals content. Res2DInv inversion modeling is used to obtain true chargeability and resistivity value in subsurface. The relationship between them is obtained from depth slicing of all inversion results. Evidently, the geometry and position of subsurface objects with contrasting in chargeability and resistivity can be identified with physical modeling fieldscale. Dipole-dipole and Wenner configuration are able to determine the TDIP responses in subsurface. Dipole-dipole configuration has main advantage, it is able to separate chargeability laterally, while Wenner produces deeper penetration. In this research, the relation between chargeability (m) and the iron-ore content (x) of the sphere targets using Dipole-dipole and Wenner configuration are m = 0,07e0,033x and m = 0,87e0,008x, while on the block targets m = 0,21e0,009x and m = 0,79e0,007x respectively. In this research, correlation between the resistivity and the metalic mineral content in the target can not be obtained with good result.

Induced Polarization (IP) method is one of geophysical method. This method is develop the resistivity method with additional measurement in ability of the ground to store electrical charge. Electrode polarization process is a major factor to the IP response in medium that contain metallic minerals. The relationship between the metallic mineral content and TDIP will be quantized. The TDIP response is influenced by porosity, grainsize, clay and metallic mineral content. Measurement is performed of artificial samples that made of iron ore mixed with quartz and cement. The samples are varied in iron ore content (0%-80%), grainsize (65-300) micron and clay content (0%-25%). If Fe-total content greather, then rise exponentially in chargeability M=1.53exp(0.029Fe). When the density becomes larger, chargeability rise exponentially M=0.347exp(0.852Dens). The presence of clay will enlarge the chargeability and minimize resistivity exponentially Rho=15.06exp(0.02C). Chargeability is lower and resistivity is higher for larger grainsize. Increasing water saturation will reduce the value of resistivity Rho=600,7exp(-0.028W) and Rho=191.4exp(- 0.025W) for Fe-total content of 28.3% and 21.2%, respectively.

The Induced Polarization (IP) methods is an extension of resistivity method by adding ability of the ground in storing electrical charge. One of the measurement technique is done in time domain, hereinafter referred to as Time Domain Induced Polarization (TDIP). TDIP responses measured on the surface are affected by the physical properties of the subsurface. Research in TDIP response modeling studies is performed to obtain a quantitative relationship between response to metallic mineral content at subsurface. The relationship can be obtained by forward and physical modelling. The forward modeling produces a curve that connects TDIP response to the subsurface parameters and an array. The laboratory-scale physical model is performed on the sand-box size (200x100x70) cm3 by varying iron-ore content in a sphere target. TDIP response measurements on physical models is done using Dipole-dipole and Wenner configuration. The relationship between the TDIP response and metal mineral content is obtained by comparing the results of measurements on physical modeling and forward modelling. There is good appropriatement between the theoretical curves and measuring results of the physical modelling. The greater of iron-ore content on the target, increasing in the TDIP response.

Modelling studies of Time Domain Induced Polarization (TDIP) performed to obtain the relationship between parameters responses to metallic mineral content. This study includes mathematical, forward, physical and inversion modelling. Mathematical modelling is done by solving the Laplace equation to obtain the IP responses. Forward modelling is done by developing a numerical workflow to generate theoretical curves. Physical modelling obtained the data from various parameters of target measurement. TDIP responses that compared with the theoretical curves are the results of mathematical modelling. The best response of IP can be obtained by inversion modelling. TDIP responses measurement by varying target’s metallic mineral content is done for understanding the relationship between them. The amplitude of IP responses in forward modelling is determined by target’s radius and depth ratio, and ratio of background resistivity and target’s resistivity. The higher target’s radius and depth ratio, the higher the amplitude. There is a good correlation between TDIP responses to the presence of the target and the possibility of metallic mineral content in target.