Application of Empirical Mode Decomposition and Independent Component Analysis for the Interpretation of Rock-Mineral...

Rock-mineral spectrum is a mixture of varied mineral spectra, through which we can obtain information about its components quickly and conveniently without any damage to the sample. Empirical mode decomposition (EMD) cannot directly decompose source signals from information of the mixture, and independent component analysis (ICA) requires the number of mixed signals to be no less than the number of source signals. Combining these two methods, mixed signals can be decomposed using EMD method to obtain intrinsic mode function (IMF), while certain IMFs together with mixed signals can be used as input data matrix of ICA to obtain the source signals. This method overcomes the shortcomings of IMF and ICA. Studies have shown that, the higher content of source signals contained in the mixed signal, the better estimation can be obtained through EMD and ICA. The number of IMFs that participate in ICA decomposition determines the number of approximation of source signals. The accuracy of source signal estimation increases with the correlation coefficient between IMF and mixed signals. By applying this method to quantitative analysis of rock-mineral spectrum, information of the component minerals in rock-mineral can be obtained, which improves the efficiency of component analysis in detecting rock-minerals outside.