Identification of mineralization features and deep geochemical anomalies using a new FT-PCA approach

Abstract

The analysis of geochemical data in frequency domain, as indicated in this research study, can provide new exploratory information<br />that may not be exposed in spatial domain. To identify deep geochemical anomalies, sulfide zone and geochemical noises in Dalli Cu–<br />Au porphyry deposit, a new approach based on coupling Fourier transform (FT) and principal component analysis (PCA) has been<br />used. The relationship between frequency attributes of surface geochemical data and mineralizing depth has been discussed. To<br />determine the exploratory features in different frequencies, high- and low-pass filters have been performed on frequency domain; PCA<br />method has been employed on these frequency bands separately. The results of this study have identified the mineralizing elements and<br />showed the relationship between high- and low-frequencies and depths of anomalies. The geochemical halos of mineral deposits at<br />different depths affected frequency distribution of elements in the surface. The information obtained from geophysical studies and<br />exploration drillings, such as, trenches and boreholes, confirm the results of FT–PCA method. This new approach is very effective tool<br />to identify the promising anomalies and deep mineralization without drilling.