Submit Manuscript | http://medcraveonline.com Introduction Geomagnetic surveying is usually done nowadays to map a geological feature mainly at exploration stages detections of mines. The problem facing requires an inverse solution. The Gauss’ theorem 1 implies that if one knows the feld distribution on a bounding surface, infnitely many equivalent sources distributions inside the boundary can produce the known feld. Thus, any geomagnetic feld measurement performed on the surface of the Earth can be reproduced by an infnitesimally thin zone of magnetic dipoles beneath the surface. From a mathematical perspective, this means there is no depth resolution inherent in magnetic feld data. An approach for inverting geomagnetic data is to divide the Earth into a large number of cells of fxed size but of unknown susceptibility. Although the problem is not unique, if we choose an objective function for the model to ft the data using a global minimization technique such as, 2 minimization of a weighted model norm for a reference model is considered. This method allows the interpreter to guide the inversion by varying the weighting according to the available information 3 choose to minimize the total volume of the causative body so that the fnal model is compact and structurally simple 4 minimized the moment of inertia of the causative body for the centere of gravity or an axis passing through it. Their inversion result is guided by the estimate of the central depth and dip of the causative body. These approaches have merit, but they are not fexible enough to handle problems we are concerning. The 5 presented an inverting method for magnetic data to recover 3-D susceptibility models. To allow the maximum fexibility for the model to represent geologically realistic structures, they discretized the 3-D model region into a set of rectangular cells, each having a constant susceptibility. The number of cells is generally far greater than the number of the data available, and thus they solved an underdetermined problem. Solutions are obtained by minimizing a global objective function composed of the model objective function and data misft. The algorithm can incorporate a priori information into the model objective function by using one or more appropriate weighting functions. The inversion model can be either susceptibility of its logarithm. If susceptibility is chosen, a positivity constraint is imposed to reduce the nonuniqueness and to maintain physical realizability. In this study, we use the 5 method to delineate the magnetic ores in the study area. The study presented here is typical and similar studies can be done to detect various ferrous mines. Study area and data acquisition The Chenar ferrous mine is located within the 5 km vicinity of Chenar village placed in 16 km north of Asadabad city of Hamadan Province of Iran. The access road to the mine is the road which connects the Chenar village to Asadabad city. The geographical location and the access road to Chenar ferrous mine are shown with green colour in Figure 1 (A). The area of interest is shown in red colour. A selected portion of Figure 1 (A) is shown in Figure 1 (B). The black box indicated in Figure 1 (B) is the top view projection of an imaginary box used to illustrate our analysis. The data was acquired in 4300 pre-planned location using a Canadian GEM-GSM 19 T series magnetometer in 10 days. The spatial resolution of the data in each line was 20 meters Figure 1 (C). Figure 1 (A) Location of the study mine in the satellite image and the way of green access to the mine. (B) The black box shows the top view of the analysis cubes in the study area. (C) The data acquisition points where the magnetometer was placed and recorded the magnetic value of the Earth. Phys Astron Int J. 2020;4(5):172‒175. 172 ©2020 Ala Amjadi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Geomagnetic inversion for delineation of ore deposits in chenar mine Volume 4 Issue 5 - 2020 Ahmad Ala Amjadi, 1,2,3 Mohsen Kushki 1 1 GeoMine Company, No. 6, Block 37, West Shabnam Ave, Tehran, Iran 2 North Drilling Company (NDC), No. 2127, Corner of Del Afrooz St.,Valiasr St., Tehran, Iran 3 International Institute of Earthquake Engineering and Seismology (IIEES), Iran Correspondence: Ahmad Ala Amjadi, GeoMine Company, No. 6, Block 37, West Shabnam Ave., 2nd Golha St., Entesarieh, North Karegar, Tehran, Iran, P.O. Box: 14139-93317, Email Received: September 24, 2019 | Published: October 12, 2020 Abstract In this manuscript, we have performed an applied geomagnetic inversion study in the Chenar ferrous mine near Asadabad-Hamedan of Iran. The principal purpose of this study was to depict and visualize the ore massif of the Chenar ferrous mine in details and to fnd the suitable locations for geological drilling cores. In this study, 4300 Geomagnetic readings were acquired over a ten-day data acquisition period with a Canadian-built 2019 GEM- GSM19T magnetometer. The analyzes of the geomagnetic data in the Chenar ferrous mine successfully identifed the susceptible zones in the area of study, and we have suggested the location of six drilling points in the mining area for further investigation and verifying of geophysical data. Our results depict four massifs which are extended as veins. According to the dimensions of the magnetic halos, our geophysical result estimates the ore deposit to be about two and a half million tons for three of the massifs in the Eastern part and 250 thousand tons for the fourth massif in the Western part of the study region. Keywords: geomagnetic, geophysics, ferrous mines, exploration Physics & Astronomy International Journal Research Article Open Access