Study On Multi-scale Remote Sensing Prospecting Model Of Porphyry Copper Deposits In The Metallogenic Belts Of Southern Three Rivers Region,Southwest China

Southwest "Sanjiang",due to the Nu River,Lancang River and Jinsha River Sanjiang co-named.The southwest Sanjiang area is the main component of the East Tethys which located in the Eurasian plate and the Indian plate transfer site Tethys Himalayan metallogenic field,the area of mineralization complex and diverse because of its composite orogenic effect.There is a strong multi-stage tectonic activity,magmatic rock activity and metamorphism,and mineralization is significant,and the metallogenic effect is very favorable.It is a very favorable metallogenic environment,which is extremely important for copper,lead,zinc,gold and silver in China.Area,the world's more rare polymetallic metallogenic field,has been one of the hot areas of China's prospecting work place.This paper summarizes and analyzes the data collected in the study area.In order to make better use of remote sensing technology to understand the metallogenic regularity of the study area and to be able to carry out the metallogenic prediction work in the study area,this study will be divided into three scales(typical deposit scale,ore set zone scale,metallogenic belt scale).Select the Shangri-La mine area in the middle of the area as the representative of the mine area,select the largest granite porphyry type copper deposit in the Shangri-La mine area as the typical deposit representative.According to the order of the Pulandian deposit,the Shangri-La mine area,the southwest Sanjiang metallogenic belt,first,the geological characteristics of the typical deposits in the ore deposit area are fully understood and analyzed,and build the typical mineralization model.And then summarizes the mineralization characteristics and metallogenic regularity of the ore deposit area,establishes the remote sensing prospecting model of the mine area.Finally,on the basis of mineralization characteristics and metallogenic regularity of the ore deposit area,the metallogenic characteristics and metallogenic regularities of the ore deposit area are enlarged to the macroscopic background of the metallogenic belt,the metallogenic belt is directly identified,the metallogenic belt is established and the prospecting model is established.In this regard,this paper mainly carried out the following research:(1)Collection and collation of multi-source data(geological data and remote sensing data)in the corresponding regions of the study area,in the Pran typical deposits has carried out field geological survey work,its surrounding rock alteration,stratigraphy,structure,rock,alteration zoning and remote sensing anomaly verification carried out a detailed research work.After fully understanding the geological background and metallogenic model,the prospecting signs of the Polan typical porphyry copper deposits are extracted and extracted by using ASTER and World view remote sensing images.Then,in the 300 m × 300 m standard grid geostatistics unit established on the ArcGIS platform,the quantitative analysis was carried out,and six favorable ore-controlling variables were obtained:linear structural anomalies,line loop intersection exception,geological complexity,favorable metallogenic rock mass complexity,favorable mineralization implicit rock mass complexity,and remote sensing alteration anomalies.The correlation between the ore body and the rock mass is the largest,followed by the anomalous remote sensing alteration,the linear structure anomaly,the geological complexity,the line intersection density,and the complexity of the buried rock,indicating that the rock mass and the linear structure The ore body has a good indicator function,and the remote sensing prospecting model of the Pran typical deposit is established.(2)Based on the study of the metallogenic regularity of the Pran typical deposit,the Landsat 8 OLI remote sensing image is used to extract the Shangqi La mine area prospecting mark.Then,in the 2km × 2km standard grid geologic statistical unit established on the ArcGIS platform,The results show that there are five favorable ore-controlling variables in Shangri-La mine area: anomaly of remote sensing structure,line intersection density,favorable ore-forming strata,favorable ore-forming rock and remote sensing alteration.According to the size of the known copper deposits in the region,the correlation between the corresponding buffer zone and the ore-controlling variables is determined: the correlation coefficient of the high-value area,the high-value zone of the linear structure anomaly,the favorable ore-forming rock mass,the favorable ore-forming strata and the high-value zone of the remote sensing alteration are decreasing.Based on this,the remote sensing prospecting model of the ore marsh area is established,which is the basic preparation for the metallogenic regularity of the porphyry copper deposit in the south-central Sanjiang metallogenic belt.(3)On the basis of summarizing the metallogenic regularity of the ore deposit area,the metallogenic characteristics and metallogenic regularity of the ore deposit area are enlarged to the macroscopic background of the metallogenic belt,and the metallogenic belt prospecting signs were directly determined.Mosaiced prospecting information extracted from multi view Landsat 8 OLI remote sensing images,and quantified in the 10 km × 10 km standard grid geostatistics unit established by ArcGIS platform to obtain four favorable ore-controlling variables in the metallogenic belt: linear structural anomaly,favorable metallogenic strata,favorable ore-forming rock and remote sensing alteration.According to the size of the known copper deposits in the region,the correlation between the corresponding post-buffer analysis and the ore-controlling variables is as follows: the correlation coefficient of the favorable ore-forming strata is the largest,followed by the linear structural anomaly variable,the rock profitability variable,Remote sensing alteration anomaly variable,according to the establishment of the southwest Sanjiang metallogenic belt in the south of the remote sensing prospecting model,comprehensive superposition analysis after the delineation of ore prospecting prospecting area.