Identification of hidden mineralized and non-mineralized zones using spectral analysis of geochemical data

Document Type : Research Paper

Authors

1 Department of Mining Engineering, University of Gonabad, Gonabad, Iran

2 Centro de Geofísica, Universidade de Lisboa, Campo Grande Ed. C8, 1749-016 Lisbon, Portugal

Abstract

Detection of dispersed and blind mineral deposits is an important aim in the mineral exploration. Detailed exploratory operations such as drilled boreholes which are performed for exploration of mineral deposits in the depth caused high cost and risk. In this research, a new scenario based on spectral analysis of geochemical data has been utilized for prediction of mineralized zones in the depth without any additional cost. The variations of mineralized elements from the surface to the depth are predicted and delineated by using this approach based on surface geochemical data. This proposed approach is the state-of the-art application of two-dimensional Fourier transformation (2DFT) for geochemical image processing. This approach which is named frequency coefficient method (FCM) has been defined based on the behavior of elements in the frequency domain. In this study, the FCM shows two Pb and Zn mineralized zones at the surface and moderate depth and a non-mineralized zone at the profound depth in Chichakloo Pb–Zn mineralization. Finally, the results of FCM have been validated and confirmed by the results of drilled boreholes and geophysical surveys.

Keywords


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