Mineralization And Ore Prediction Of Longquanzhan Gold Deposit In Yishui, Shandong Province

Based on the metallogenic analysis, the mineralization and ore prediction in Longquanzhan gold deposit were studied by means of extraction of remote sensing alteration information, tectonic geochemistry, EH-4 geophysical sounding etc. The main conclusions were made as follows:1. The main orebodies of Longquanzhan gold deposit occurred in altered mylonite and cataclasite of Yishui-Tangtou fault. The higher content of SiO2 in ores related to the aggregation of Si in the process of beresitization. The lower content of CaO, MgO, MnO, TiO2, P2O5 in ores showed these compositions were brought out in the process of alteration and mineralization. According to the La/Yb-REE content scheme, the material compositions in ores and rocks came mainly from sedimentary rocks, and the initial materials of chorismite and greenschist possibly contained the composition of basic lava. The geological condition of mineralization included ore-controlling structure, material source and heat source of mineralization. Metallogenic epoch of Longquanzhan gold deposit was the time after the formation of Malanggou group stratum in Cretaceous. The mineralization of Longquanzhan gold deposit related to the hydrothermal covection metallogenic system in which meteoric water participated2.The remote sensing alteration information was extracted according to USA LANDSAT-7ETM data in 1200km2 of Longquanzhan and its periphery. The distribution of iron and argillic alteration related closely to the areal area of granite porphyry, granodiorit, monzogranite and Cambrian system. Four ore-finding perspective areas were determined according to the distribution of remote sensing alteration information and geological condition.3. Three successive abnormities of Au element were found through surficial tectonic geochemistry survey of 16km2 in Longquanzhan. The aggregation of Au related closely to Pb, Ag, Cu, Mo, Bi, As, Ba according to correlation analysis, cluster analysis and factor analysis. Combined with geological analysis, the optimal indicator elements association of ore prediction were determined as Au-Ag-Pb-Cu-As-Ba.4. Based on the distribution of tectonic geochemistry abnormity and surficial ore occurrence, EH-4 geophysical sounding were carried out in 16 and 111 exploratory lines. Two prospecting targets were delineated according to the abnormity of tectonic geochemistry and EH-4 geophysical sounding.