Petrology and Geochemical Characteristics of Burnt Rocks in Typical Mining Areas in Northern Shaanxi
Basic study on burnt rock plays a crucial role in the prevention and control of burnt rocks water hazard.In order to understand the petrology and geochemical characteristics of the burnt rock,taking the Zhangjiamao mine field in Yushen mining area in northern Shaanxi as an example,the main elements,trace elements and rare earth elements of the burnt rock were determined and analyzed in detail through field investigation and core sampling in boreholes.The results indicate that the upper and lower parts of the rock mass,as well as the adjacent rock layers,belong to plate-like barbecue rocks,lava rocks,and layered barbecue rocks,respectively.The lithology,color,and pore development characteristics of different types of burnt rocks vary greatly with the degree of roasting.The main chemical composition of burnt rock is SiO2,followed by A12O3.The rock samples are mainly siliceous aluminum,with relatively low content of magnesium iron components.The average Fe2O3+MgO content is 4.76％,and there is little difference between the original rock and the burnt rock,and between the original rock and the burnt lava sample.The content of lithophile elements Rb and Ba in the burnt rock is higher than that in the original rock,while the content of Sr is low,and Cs and Eu are relatively depleted.The Zr content in high field strength elements is generally higher in all samples,and different types of rock samples have the characteristics of Y,Zr,and Pb enrichment.The changes in high field strength elements under burning are not significant.The REE abundance trend curve of the sample shows a differential distribution,and the average value of standard sedimentary rock and upper crust is more similar than that of chondrite.The study results will provide basic support for studying the genesis and formation environment of burnt rocks.
burnt rockgeochemical characteristicsrare earth elementsburning effectwater hazard prevention and control
万方数据
维普
