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Dykes play a key role in various geologic environments. Here, we show how we employed profile magnetic data to perceive and identify the number of dykes and their parameters by a particle swarm optimiser scheme. The results deduced from this inversion include identification and estimation of the magnetic dipole moment, depth, half-width, magnetisation angle, and origin location (dyke parameters) of dykes. Two synthetic models demonstrate this scheme: the first model tests the impact of a third-order regional anomaly and the second model considers the effect of adjacent structures. Besides, we provide two case studies related to mineral exploration, viz., the Parnaiba basin from Brazil and the Pishabo Lake example from Canada. The subsurface dyke parameters estimated from drilling information and the available literature were consistently matched with those achieved from our inversion scheme, thereby demonstrating the effectiveness of the particle swarm optimisation scheme. [ABSTRACT FROM AUTHOR]

We have developed a new method for the interpretation of a magnetic anomaly profile by idealized-geometrical bodies using the variance analysis. This method is based on estimating the fourth horizontal derivative of the magnetic data profile. The advantage behind the use of the fourth horizontal derivative method is to reduce the regional background effect. The model parameters estimated are the depth and shape of the buried body using all available window lengths (s-value). Then, the variance value for the calculated depth at each shape value is estimated using all available s-values. The minimum variance is considered as the best criterion for determining the best-inverted parameters (depth and shape). The developed method has been verified on some noise free examples. Following that, the accuracy of the method was assessed by studying the impact of synthetic data with 5%, 10%, and 15% random noise, the effect of the regional background, the influence of interfering structures, and the selection for the wrong origin of the body. The presented method has been successfully applied to three real case studies from Brazil and India from mineral exploration. [ABSTRACT FROM AUTHOR]