One of the most important goals of MAGNETIC data interpretation is to determine location, depth and shape of the MAGNETIC ANOMALY. Extensive use of MAGNETIC surveys in the field of mineral exploration, geology and environmental application make earth scientists to present suitable interpretation schemes.Neural networks are part of a much wider field called artificial intelligence which have computer algorithm that solve several types of problems. The problems include classification, parameter estimation, parameter prediction, pattern recognition, completion, association, filtering, and optimization. The NNs are used in different aspects of interpretation and modeling of geophysics data. They are used for inverting geophysical data involving problems for which no easy solutions exist.In this paper, Feed Forward Neural Network (FNN) is used for the MAGNETIC ANOMALY modeling with assumption an infinite depth extent dike. The method can estimate all the geometric parameters of the dike; horizontal location on profile, width, depth and dip.We used a three layer FNN; consisting of 11 neurons in the input layer, 20 neurons in the hidden layer and 4 neurons in the output layer. For the first and hidden layers, and the last layer sigmoid and linear activation functions are used, respectively. Here, the horizontal location, width, depth and dip of the dike were defined as the output and the MAGNETIC profile data as the input of the neural network. The training of the network was done through synthetic data which were produced by forward modeling.For preventing the neural network from holding to any particular sequence, the input data were assigned in a random and then, the profile related to these data was obtained by dike equation. For the FNN to recognize the pattern of the profile data, some parameters are defined as the input of the FNN. These parameters should be separated. In other words, they must have a relation with the geometrical parameters of the dike. In definition of the parameters from the ANOMALY curve, maximum and minimum points, width of curve in points of 75% and 50% of maximum, area of positive and negative parts of ANOMALY curve are used. Furthermore, the width and depth of the dike may be found through using a horizontal derivative of ANOMALY and a derivative of Hilbert transform.Horizontal derivation of ANOMALY curve and Hilbert transform of horizontal derivation, especially from their intersection points, are also used as input parameters of neural network.The validity of this method was tested by using of noise-free and noise-corrupted synthetic models that satisfactory results were obtained. Then the Morvarid mine, which located at a distance of 30Km south east of Zanjan, near Aliabad village, is chosen as a real data application. The outputs show a good accordance with the Euler method and the tranches results.The FNN inversion provides satisfactory results despite the noise. Various techniques are applied for interpretation of MAGNETIC data. Most of them estimate only the depth. So, careful determination of dip, depth and width of the dike are the benefits of the use of the FNN.

Mapping the edges of magnetized bodies is fundamental to the application of MAGNETIC data to geologic mapping. Whether as a guide for subsequent field mapping or as a predictive mapping tool in areas of limited exposure, delineating lateral magnetization changes provides information on not only lithological changes but also on structural regimes and deformation styles and trends. Adding contact locations to maps of the MAGNETIC field or enhanced versions of the field (derivatives, transforms, etc. ) improves significantly the interpretive power of such products. Furthermore, this has recently become particularly important because of the large volumes of MAGNETIC data that are being collected for environmental and geological applications. Hence, a variety of semi-automatic methods, based on the use of derivatives of the MAGNETIC field has been developed to determine MAGNETIC source parameters such as locations of boundaries and depths. Almost all methods that determine contact locations are based on calculating some function of the MAGNETIC field that produces a maximum over a source body edge. Finding the maxima is then efficiently done with the curve-fitting approach of Blakely and Simpson (1986). Gravity and MAGNETIC data are usually processed and interpreted separately, and fully integrated results basically are created in the mind of the interpreter. Data interpretation in such a manner requires an interpreter experienced both in topics concerning potential field theory and the geology of the study area. To simplify the joint interpretation of data, the automatic production of auxiliary interpreting products, in the form of maps or profiles, is useful to help a less experienced interpreter or when investigating regions with poorly known geology. Fortunately, a suitable theoretical background for the joint interpretation of gravity and MAGNETIC anomalies is well established and can serve promptly in generating such products. Because of its mathematical expression, this theory is commonly referred to as the Poisson relation or the Poisson theorem. This theorem provides a simple linear relationship connecting gravity and MAGNETIC potentials and, by extension, field components that are commonly derived from geophysical surveys. To validate this, an isolated source must have a uniform density and magnetization contrast. The relationship, however, is independent of the shape and location of the source. Therefore, the MAGNETIC field can be calculated directly from the gravity field without knowing the geometry of the body or how magnetization and density are distributed within the body and Vice Versa. Therefore, a MAGNETIC grid may be transformed into a grid of pseudo-gravity. The process requires pole reduction, but adds a further procedure which converts the essentially dipolar nature of a MAGNETIC field to its equivalent monopolar form. The result, with suitable scaling, is comparable with the gravity map. It shows the gravity map that would have been observed if density were proportional to magnetization (or susceptibility). Comparison of gravity and pseudo-gravity maps can reveal a good deal about the local geology. Where anomalies coincide, the source of the gravity and MAGNETIC disturbances is likely to be the same geological structure. Similarly, a gravity grid can be transformed into a pseudo-MAGNETIC grid, although this is a less common practice. Pseudo-gravity transformation is a linear filter which is usually applied in the frequency domain on MAGNETIC data. This filter produces an applicable result because interpretation and quantifying the gravity ANOMALY is easier than MAGNETIC ANOMALY. Filtering (enhancement techniques) is a way of separating signals of different wavelength to isolate and hence enhance anomalous features with a certain wavelength. One of the enhancement methods in MAGNETIC data filtering is Total Horizontal Derivative (THDR) designed to look at Maxima in the filtered map indicate source edges. It is complementary to the traditional filters and also first vertical derivative enhancements techniques. It usually produces a more exact location for faults than the first vertical derivative, but for MAGNETIC data it must be used in conjunction with the other transformations e. g. reduction to pole (RTP) or pseudo-gravity. Computing horizontal gradient of the pseudo-gravity ANOMALY and mapping the maximum value of this causes edge detection of the MAGNETIC causative body. In this paper this method is applied on synthetic MAGNETIC ANOMALY and also on the MAGNETIC ANOMALY from the Gol-Gohar area in Sirjan which demonstrate a 30m width body.

MAGNETIC ANOMALY detection (MAD) is a passive method for airborne detection of subsurface objects. Light, radar and sound waves are unable to pass through the open air into the sea water environment and penetrate deep into the water, weaken or return to the air environment. On the other hand, the MAGNETIC field force lines on this boundary are unchanged. MAD method is based on measuring the smallest changes or anomalies caused by the earth's MAGNETIC field due to the passage of a ferro-MAGNETIC object and the MAGNETIC bipolar field generated around it, and especially in shallow waters, is one of the most efficient methods. Due to the rapid reduction of the MAGNETIC field by increasing the distance, the MAGNETIC disturbance generated by the MAGNETIC target in the distance, usually buried in MAGNETIC noise, in other words, the signal-to-noise ratio (SNR) decreases. In this paper, in order to improve the detection performance of MAGNETIC impairment in low SNR, a hybrid method of MAD based on empirical mode decomposition (EMD) and minimal entropy method is proposed. In order to evaluate the performance of the method, an electronic measuring device has been constructed and MAGNETIC data have been fieldly harvested from caspian sea in Anzali port area. These data impregnated with environmental MAGNETIC noise have been investigated by entropy method. According to the entropy feature, MAGNETIC ANOMALY is detected whenever entropy degrades below the defined threshold. In this way, the proposed method for detecting weak MAGNETIC anomalies is also effective. The test results indicate a high probability of detection of the proposed method for low input SNR. Compared to the original signal SNR with-10 dB, the reconstructed signal SNR has improved to 8 dB. In addition, the total time of updating the parameters of the probability density function (PDF ), of noise is about 0. 075s obtained.

The normalized full gradient (NFG) method defined by Berezkin (1967, 1973 and 1998) is used for downward continuation maps. Analytical downward continuation is a method of estimating the field closer to the source, and, consequently, it results in a better resolution of underground rock distribution. However, the usefulness of this process is limited by the fact that the operation is extremely sensitive to noise. With noise free data, downward continuation is well defined; it is unnecessary to continue below the source level. In the presence of noise, the amplification of high frequencies is so strong that it quickly masks the information in the original profile. Low-pass Fourier filtering, while suppressing such noise, also blurs the signal, overcoming the purpose of sharpening by downward continuation.Despite the above-mentioned problems, most geophysical experts have long been interested in this technique because of its importance to mineral exploration. Furthermore, this method is a fast and cheap way to determine the initial depth of the subsurface features, especially where there is no other geophysical or well-logging data. A good analytical downward continuation process could provide subsurface general images, allowing an enhanced interpretation. Also, analytical downward continuation has the ability to determine accurately both the horizontal and vertical extents of geological sources.The NFG method nullifies perturbations due to the passage of mass depth during downward continuation. The method depends on the downward analytical continuation of normalized full gradient values of MAGNETIC data. Analytical continuation discriminates certain structural anomalies which cannot be distinguished in the observed MAGNETIC field. It can be used to estimate location, depth to the top, and center of the deposit that is applied also for detecting oil reserviors and tectonic studies. One of the important parameters to estimate the accurate shape of the deposit is true selection of the harmonic number. In this paper, the correct harmonic number is determined and then this method will be tested for noise-free and noise-corruption synthetic data. Finally, 2D and 3D of this method are applied to real data from Zanjan’s Morvarid mine.The Morvarid mine is located at a distance of 23 km southeast of Zanjan, near Aliabad village. Hematite and magnetite are the major minerals in the mine in which MAGNETIC exploration has been performed to find anomalies around the mine, near outcrops of the region. From the IGRF model, the geoMAGNETIC field of this region is calculated at 47680 nT (inclination=54.7o, declination=4.5o).The results of the method were satisfactory for a dike. After applying the method, a general view of deposit structure was obtained that helped us to make a fast interpretation. 2D and 3D results of NFG method satisfied the results of trenches and drilling in the region are under study, as well. The final result of this method shows that the deposit begins from the low depth to approximately less than 100 meters. This modeling yeilded satisfactory results for drilling in the region. The results of the drillings show that the lowest depth of the deposit is about 6 meters.Finally, 2.5D modeling of th edeposit was done using Modelvision software that had the same results. This method can easily be applied for gravity and microgravity data.

Background and Aims: Disc displacement is the most common temporomandibular joint disorder and MAGNETIC resonance imaging (MRI) is the gold standard in its diagnosis. This disorder can lead to changes in signal intensity of MAGNETIC resonance (MR). The purpose of this study was evaluation of correlation between relative signal intensity of MR images of retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle with type of anterior disk displacement and condylar head flattening in patients with temporomandibular disorder (TMD).Materials and Methods: In this retrospective study, 31 MR images of patients who had anterior disc displacement were evaluated. After relative signal intensity measurement for retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle, the correlation between relative signal intensity and type of anterior disc displacement was evaluated with repeated measure ANOVA test. In each of these 3 areas, t-test was used to compare the groups with and without condylar head flattening.Results: The correlation between relative signal intensity of MR images and type of anterior disc displacement in retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle was not significant. There was also no statistically significant correlation between relative signal intensity of MR images and flattening of condylar head in retrodiscal tissue, superior and inferior head of lateral ptrygoid muscle (P>0.05).Conclusion: According to findings of this study, relative signal intensity of MR images in retrodiscal tissue, superior and inferior head of ptrygoid muscle is not a good predictor for type of anterior disc displacement and flattening of condylar head. It seems that this cannot be used as a diagnostic marker for TMD progression.

The MAGNETIC data collected from airborne surveys need to be interpreted after processing. The most important information gathered from the interpretation stage, is the depth and horizontal position of anomalies. Various methods are developed for gathering these data. One of these methods is Euler deconvolution that is based on Euler’ s homogenous equation. Euler's method is one of the fastest semi-automatic methods for determining the depth of buried MAGNETIC and gravity anomalies. Its results are highly dependent on the structural index, Euler window size, and depth calculation error. This method identifies the depth and trend of changes in the depth of anomalies very well. The geological information of the study area is important for the application of this method. In this method, the potential field and its first-order derivatives are used in different directions to determine the position and depth of the potential field source. In this paper, by using this method, the depth, and boundaries of anomalies in the Lake Blatchford area of Canada are investigated. The obtained results indicate that most anomalies in this region have shallow to medium depth.

KC5 copper exploration prospect is located 80 Km to the northwest of Bardaskan and 4 Km to the Northeast of Dahaneh Siah copper mine in Khorasan Razavi. KC5 and Dahaneh Siah areas belong to Sabzevar geological Zone. Copper mineralization is observable mainly as secondary minerals such as Malachite and Chlorite which fills joints and fractures in a faulty contact at the boundary of the volcanic and Oriyan sedimentary (carbonaceous and tuff) rocks. High intensity ellipsoidal aeroMAGNETIC ANOMALY overlies the boundary between the volcanic and carbonaceous rocks which follows old abandoned copper mines and extends to the KC5 prospect and Dahaneh Siyah area. Studies indicate the presence of magnetite up to maximum.5% in the volcanic rocks. MAGNETIC susceptibilities of the volcanic rocks in the KC5 west; KC5 east and Dahaneh Siyah show that this parameter is 2 times smaller in the first area than in the second and third. MAGNETIC anomalies of the two volcanic units in the KC5 east are similar but their amplitudes are lower than the anomalies produced by the same units in the KC5 west. ANOMALY amplitudes of the Dahaneh Siyah volcanic are smaller than those produced by the same volcanic unit in the KC5 west and east. Lower MAGNETIC susceptibilities of surface volcanic samples in the KC5 west and their higher amplitude anomalies in comparison with the anomalies from similar volcanic units in the KC5 east and Dahaneh Siyah implies that the source of the ANOMALY and main mineralization at KC5 west must be deep. Correlation of aeroMAGNETIC ANOMALY with old abandoned copper mine (including the Dahaneh Siyah copper mine and the KC5 prospect area), uuper boundary of the volcanic and carbonaceous sediment and geochemical ANOMALY of the region are indications of the relation of main mineralization with aeroMAGNETIC ANOMALY.

Earnings-based ANOMALY, known as post-earnings announcement drift, could be regarded as delayed price response to earnings information that results in earning abnormal returns. The accrual ANOMALY refers to the fact that the current level of accruals is negatively related to abnormal returns over the following year, which may result in earning abnormal returns. These two anomalies appear to be related closely in the sense that accruals could be regarded as the primary component contributing to earnings. The aim of this study is to examine these two anomalies in the Iranian capital market, and to explain the relationship between them.In this study a sample of 560 firm-years from the Tehran Stock Exchange in the period of 1388-1391 has been considered. The results show that earnings-based ANOMALY is different from accrual ANOMALY. Also, a hedge portfolio trading strategy that takes both forms of market mispricing, generates abnormal returns higher than those based on only unexpected earnings or accruals information.

The inevitable depletion of mineral resources, the constant deterioration of the geological and mining conditions for the development of mineral deposits and the restoration of raw materials from mining waste by recycling are all urgent problems we faced today. The solution to this problem may ensure: a considerable extension of raw material source; decrease of investments in opening new deposits; cost savings for dumping and handling of tailing dumps, disturbed land remediation; obtaining social and economic effect due to a considerable reduction in pollution of the environment. This article deals with the study of iron-containing tailings dumped at the tailing dumps of ore-refinery and processing facilities located in Kursk MAGNETIC ANOMALY (KMA GOKs), where samples were taken for this study. The article contains the results of the materials composition study, namely: chemical composition, the mineral-petrographic study of thin and polished sections, grain size distribution and physical-mechanical properties of tailing samples. Regularities were revealed for the change of the useful component content due to gravity differentiation. It was also noted that the sulphur content increased near the pulp discharge outlet due to pyrite accumulation. The ratio of ore minerals in tailings and the fineness ratio of the sand fraction were measured. The examination with a focused beam microscope with x90 to x600 magnification showed a variety of grain sizes and shapes that facilitate using tailing materials after additional processing in the construction industry as sand.