Geological Evaluation And Alteration Information Extraction With Remote Sensing Image In Fengqing Area Of Yunnan Province

Mineral resources are rich, ore-formation stratigraphy and tectonic-magmatic are in good conditions in Fengqing, Yunnan province.. Under the premise of increasing difficulty of conventional prospecting work, the application of remote sensing technology to find new deposits plays an important role, which can quickly identify the wallrock alteration anomalies. Through the extraction of alteration information to circle metallogenic area, which provide a reliable reference basis for conventional prospecting methods.This article combined the remote sensing and mathematical geology, and used SPOT 6, ASTER, Landsat 8 satellite image data as the basic data, Combined with the geological survey data, make the geologic evaluation of remote sensing and extract the information of mineralized alteration in the area.In this paper, following results have been achieved:(1) To prepare for the subsequent research, we analyzed the research content and the characteristics of remote sensing data, made pretreatment of all remote sensing data, then made the geologic evaluation image of remote sensing and extraction image of alteration information.(2) By use the SPOT-6 image of Fengqing in Yunnan province, combined with the previous geological data, we established the evaluation signs of lithology, stratμm and structure, we produced the geologic evaluation chart of the study area.(3) Combined with the existing geological survey data, On the premise of the extracting alteration information of geological and spectrμm basis, we sμmmarized the method of extracting the anomalies in mineral alteration. Based on the removing of the interference information to the alteration information extraction.According to the ASTER and Landsat 8 image data in research area, we take eprincipal components analysis method to make information acquisition of iron color alteration and hydroxyl alteration based on the study of the spectral characteristics of alteration minerals, besides we also filtered and classified alteration information.(4) Make a field verification on extraction information of lithology, structure alteration. Combined with the geophysical prospecting and chemical prospecting data, we take further screening and comprehensive analysis of remote sensing information, which proves that alteration in this area using remote sensing information extraction is feasible.This research results provide important evidences for the mineral exploration work in Yunnan Fengqing region, which acts a significant meaning to metallogenic prediction of the region as well as the development of the national economy.