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Performing the power spectrum-area method to separate anomaly from background for induced polarization data: (a case study; Hamyj copper deposit, Iran)

  • Mohammad Shahi Ferdows
  • Hamidreza Ramazi
Original Paper
  • 112 Downloads

Abstract

Anomaly separation plays a critical role in mineral exploration. The power spectrum-area considers the spatial data which give rise to detecting the anomalies more significantly. Induced polarization data has been surveyed using dipole-dipole array in the Hamyj copper index. Electrode spacing was designed at about 20 m. The Hamyj index was explored based on the result of remote sensing and economic geology. Hamyj deposit is located about 80 km west of Birjand city, South Khorasan province, Iran. In this paper, the induced polarization from the concentration-place domain was transferred to the time-frequency domain by using two dimensional Fourier transforms in order to use the power spectrum-area method. Then, the power spectrums of induced polarization signals were calculated and differentiated by means of fractal geometry. The threshold of separation for the design of digital filter was used to filter the data. Threshold IP and filtered data was calculated by concentration-area method. Finally, IP data and filtered data were compared with each other and 72 percentages of the anomalous data corresponded significantly with each other. The results showed that the power spectrum-area method can eliminate noise; hence, anomalies can be highlighted more sharply. As far as this study is concerned, this method can be used to suggest the best places for drilling.

Keywords

Induced polarization Fractal Power spectrum-area Fourier transforms Digital filter 

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Copyright information

© Saudi Society for Geosciences 2016

Authors and Affiliations

  1. 1.Department of Mining and Metallurgical EngineeringAmirkabir University of TechnologyTehranIran

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