Remote Sensing Prospecting Information Extraction Of Liwu Copper Deposit And The Prospecting Perspectives Of Its Periphery

The Liwu copper deposit is a typical medium-sized polymetallic deposit in the northwestern of NE Muli-Jinping arc thrust tectonic zone which on the western margin of the Yangtze terrane .The Liwu copper deposit is the part of paleoproterozoic Cu(Zn) polymetallic metallogenic belt of Jiulong-Muli metamorphic-thrust complex zone. The ore exploration have taken several decades and brought gigantic benefit for the economy. However, the copper deposit confronts with the resource crisis because the prospecting is limited and the reserve resource is insufficient .The new theory and technology is the basic point of prospecting breakthrough in the area. Combined geological prospecting, geophysical and geochemical exploration, the paper has the special researches on the remote sensing information extraction of Liwu copper deposit and the prospecting perspective of its periphery, and discusses the idiographic application of remote sensing technology on the exploration information extraction which offered more all-around information for the exploration in the area.Research on the geological features and the ore-formation rule of Liwu copper deposit, the paper discusses the spacial resolution, spectral resolution, temporal resolution, economic condition and technology, chooses the remote sensing date sources and the method of remote sensing extraction. Analyze the feature of remote sensing date and the spectral character of ground object, the paper used the remote sensing technology to extraction the lithologic information, tectonic information and mineralization alternation information. Stack the geologic information, geophysical information and geochemical information with remote sensing information by geography information technology, synthesis analysis the mineral exploration information and advanced the prospecting perspective. The main content of this paper as follow:(1)Based on the analysis of research content and remote sensing date character, the paper chooses the Landsat7 ETM+ as the date source of remote sensing information extraction, and pretreatment it in order to prepare for the further research later. Based on the principle of synthetic image, the paper choose ETM+741 as the band combination of synthetic image which is the base map for visual interpretation.(2)Based on the established geologic interpret symbol, the paper extracted the lithologic information and the tectonic interpreted with visual interpretation, and analyzed the correlation between remote sensing information and the prospecting information with the mathematic statistics.(3)Based on the type of mineralization alternation and spectrum character of altered rock ,analysis the geologic basis and spectral precondition of the remote sensing information extraction, then partition the altered mineral into chalybeate altered rock , hydroxyl altered rock or carbonic altered rock in order to extraction the chalybeate anomaly information and argillation anomaly information. The paper used the principal component analysis which based on threshold method to extract the remote sensing altered information first, then contrasted it with the production extracted by the ratio method, eliminated the fake anomaly information lastly and got the filtered remote sensing information.(4)Checkout the lithologic information, tectonic information and the altered information which extracted by the remote sensing technology in the filed, and integrated it with geologic date, geophysical and geochemical exploration date for further analysis, achieved the tectonic information, altered information and other mineral exploration information.(5)Based on the synthesis analysis of mineral exploration information, the paper established the prospecting indicators and indicated that Heiniudong, Wajingou, Sunyelin,Baiyazi, Shanghaidi and other places in the surrounding areas of Liwu copper deposit have a good prospecting indicators.