摘要
烧变岩的基础研究对烧变岩水害的防治具有至关重要的作用。为了掌握烧变岩的岩石学及地球化学特征,以陕北榆神矿区张家峁井田为例,通过野外调查、钻孔岩心取样及分析测试,对该区烧变岩的主量元素、微量元素及稀土元素进行了详细的测定分析。结果表明:岩体上部、下部、邻近岩层分别属于板状烧烤岩、烧熔岩、层状烧烤岩,不同类型的烧变岩岩性、颜色、孔隙发育等特征随烧烤程度的不同而呈现较大的差异性。岩石地区化学结果表明:烧变岩主要化学成分为SiO_(2),其次为Al_(2)O_(3)。岩样主要为硅铝质,镁铁组分含量相对较少,TFe_(2)O_(3)+MgO质量百分比平均值为4.76%,而原岩与烧变岩差异性小,与烧熔岩样亦相差不大。烧变岩亲石元素Rb、Ba含量高于原岩,Sr含量低,Cs、Eu相对亏损。高场强元素中Zr含量在所有样品中普遍较高,不同类型岩样均具有Y、Zr、Pb富集的特征,高场强元素在烧变作用下变化不显著。样品的稀土元素丰度趋势曲线出现差异化分布,标准沉积岩与上地壳平均值相较球粒陨石相似性更高。研究结果将为研究烧变岩的成因及形成环境提供基础支撑。
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 SiO_(2),followed by Al_(2)O_(3).The rock samples are mainly siliceous aluminum,with relatively low content of magnesium iron components.The average Fe_(2)O_(3)+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.
作者
胡俭
王海
杨帆
姬中奎
张池
韩强
任智智
薛小渊
陈盼
HU Jian;WANG Hai;YANG Fan;JI Zhong-kui;ZHANG Chi;HAN Qiang;REN Zhi-zhi;XUE Xiao-yuan;CHEN Pan(Shenmu Zhangjiamao Mining Co.,Ltd.,Shaanxi Coal Group,Yulin 719316,China;Xi'an Research Institute(Group)Co.,Ltd.,China Coal Technology&Engineering,Xi'an 710077,China;School of Resources and Geosciences,China University of Mining and Technology,Xuzhou 221008,China)
出处
《科学技术与工程》
北大核心
2024年第23期9737-9745,共9页
Science Technology and Engineering
基金
陕西省自然科学基金重点研发计划(2022SF-046)
中煤科工西安研究院(集团)有限公司科技创新基金(2022XAYJS06,2023XAYJS02)。
关键词
烧变岩
地球化学特征
稀土元素
烧变作用
水害防治
burnt rock
geochemical characteristics
rare earth elements
burning effect
water hazard prevention and control
