高温烘烤对纳林庙岩石磁性的影响实验研究  

Experimental study on influence of high temperature baking on magnetic properties of Nalinmiao rock

作　　者：张辛亥[1,2] 窦凯 李经文 程望收 李勋广 朱辉 赵斌 陈飞 杨少雄 ZHANG Xinhai;DOU Kai;LI Jingwen;CHENG Wangshou;LI Xunguang;ZHU Hui;ZHAO Bin;CHEN Fei;YANG Shaoxiong(Key Laboratory of IWestern Mine and Hazard Prevention,Ministry of Education of China,Xi'an 710054,China;School of Safety Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China;Kaida Coal Mine of Inner Mongolia Yitai Coal Co.,Ld.,Ordos 017000,China)

机构地区：[1]西部矿井开采及灾害防治教育部重点实验室,陕西西安710054 [2]西安科技大学安全科学与工程学院,陕西西安710054 [3]内蒙古伊泰煤炭股份有限公司凯达煤矿,内蒙古鄂尔多斯017000

出　　处：《煤矿安全》2021年第9期43-47,共5页Safety in Coal Mines

基　　金：国家自然科学基金煤炭联合基金资助项目(U1361129)。

摘　　要：磁异常是煤田火灾重要的地球物理特征,为研究高温烘烤过后岩石的磁性变化规律,对磁法在火区圈定应用的中提供有效指导,利用磁化率测定系统测定了纳林庙3-1煤顶板砂岩的磁化率,分别研究了温度、粒径以及磁场强度对样品磁化率的影响。结果表明:在25~600℃整体范围内烘烤形成的烧变岩的磁化率整体上随温度增高而增大,随外界磁感应强度变大而减小。烘烤温度小于400℃时,样品粒径越小磁化率越大;通过X射线衍射实验分析了高温烘烤对岩石成分与结构的影响,表明岩石高温烘烤的过程中,菱铁矿(FeCO3)被氧化成铁磁性物质磁铁矿(Fe3O4),这是烧变岩相对常温岩石磁性增强的主要原因。Magnetic anomaly is an important geophysical feature of coal field fires. In order to study the magnetic change law of high-temperature heated rocks and provide effective guidance for the application of magnetic method in the delineation of fire zones, the susceptibility measurement system was used to determine the magnetic susceptibility of Nalinmiao 3-1 coal roof sandstone. The effects of temperature, particle size, and magnetic field strength on the magnetic susceptibility of the samples were studied. The results show that the magnetic susceptibility of the burnt rock in the whole range of 25 ℃ to 600 ℃ increases with the increase of temperature, and decreases with the increase of the external magnetic induction intensity. When the heated temperature is less than 400 ° C, the smaller the particle size of the sample, the greater the magnetic susceptibility;the effect of high temperature baking on the composition and structure of the rock is analyzed by X-ray diffraction experiments, indicating that during the high temperature baking of the rock, FeCO3 is oxidized into Fe3 O4, which is the main reason why burnt rock is more magnetic than normal rock.

关 键 词：烧变岩 磁异常 火源探测 磁化率 煤田火灾 

分 类 号：TD752.2[矿业工程—矿井通风与安全]