Hydrothermal alteration mapping based on MPH and fractal technologies using ASTER and ETM+ data in Lushi region, Henan Province, China

Satellite remote sensing can detect earth surface features from space. The environmental factors impact on remote sensing data spectral signatures used to differentiate the alteration from surrounding mineralization rocks. Hydrothermal alteration as a geological record of spatial distribution has a fractal structure. In this paper, Henan Lushi Mo-Fe polymetallic mine as study area for the ETM + and ASTER for the data source, the use of MPH (Masking, Principle component analysis, and HIS change) and fractal method combines alteration of information extracted from the study area. The method studied includes four aspects: (1) mask, (2) PCA, (3) HIS change, and (4) fractal analysis to derive threshold value of alteration. The Lushi Mo (Fe) porphyry ore-forming region is located in the Henan Province, China. It is hosted by and genetically related to magmatic arc tectonic setting. The alteration zone consists of a few porphyries with appreciable hematite surrounded by an intense silicification zone with local pervasive potassic alteration. The use of fractal theory summation law: that is, pixel brightness - an area model, remote sensing alteration anomaly extraction and classification is more effective to make up the traditional threshold method and the use of a visual histogram mutation point method to determine the shortcomings achieved good results.