Tilt梯度算法的改进与应用:以江苏韦岗铁矿为例  

An Improved Tilt Angle Method and Its Application:A Case of Weigang Iron-Ore Deposit,Jiangsu

作　　者：刘鹏飞[1] 刘天佑[1] 杨宇山[1] 张恒磊[1] 刘双[1] 

机构地区：[1]中国地质大学地球物理与空间信息学院,湖北武汉430074

出　　处：《地球科学（中国地质大学学报）》2015年第12期2091-2102,共12页Earth Science-Journal of China University of Geosciences

基　　金：国土资源部"十二五"科研专项(No.1212011121101);全国危机矿山接替资源找矿专项方法技术总结磁法专题项目(No.20089928)

摘　　要：为解决Tilt梯度存在的＂解析奇点＂这一问题,介绍了Tilt梯度位场边界识别方法,并提出了改进算法.理论分析与模型计算表明,改进的Tilt梯度方法继承了垂向一次导数与传统Tilt梯度以零值线识别边界的性质,相对其他的导数类方法（如水平总梯度模等）能够更好地识别深部弱异常;此外,改进的Tilt梯度方法物理意义明确,从理论上避免了方法的畸变性.对韦岗矿区磁异常分析表明,除工区南侧由东向西分布的A、B、C 3个主体异常外,尤其是工区5号线以北的弱异常D得到显著增强.结合钻孔资料以及磁异常反演结果,认为弱异常D可能是由深部隐伏矿体的影响产生,结合二度半人机交互反演推测矿体埋藏深度在1 000~1 200m.6号线上的DH6-6见矿钻孔位于异常D的东侧,该钻孔钻遇的薄层铁矿体位置与弱异常D的范围相吻合;另外DH6-7未见矿钻孔位于该弱异常范围以外,若向西在5号线以北布置钻孔,则有见矿可能.In order to slove the＂singularity＂problem of Tilt angle,an improved tilt angle method to detect the field source boundaries is proposed in this paper.Theoretical simulations reveal that improved Tilt angle method inherits the properties of the 1st order vertical derivative and traditional tilt gradient that identifies boundaries by zero value line and it is better for the deep weak anomalies identification than other methods such as the total module of horizontal gradient.Besides,the improved Tilt angle method avoids the abnormal degeneration due to its clear physical significance.Magnetic anomalies of the Weigang iron-ore deposit is analyzed and anomaly D is significantly enhanced except for three main anomalies of A,B,C,which indicates that the weak anomaly D is caused by deep concealed orebodies.The orebody depth is found as 1 000-1 200 m,based on the interactive inversion results of the 2.5 dimension.DH6-6 drilled hole is located in line 6,exactly on the east side of anomaly D,which coincides with the boring drilling of thin ore body.No-mine DH6-7 drilled hole is located at the outside of the weak anomaly area.It is possible that iron orebodies may be discovered if a drilled hole is arranged to the west and the north of Line 5.

关 键 词：Tilt梯度 边界识别 危机矿山 韦岗铁矿 地球物理 

分 类 号：P592[天文地球—地球化学]