基于地表数据及产状数据的交切断层建模方法研究  

Study on Modelling Method of Intersecting Faults Based on Surface and Occurrence Data

作　　者：赵义来 Alison Ord[3] 汤静如 胡荣国 杨启军[1] 汪劲草 王本达[4] ZHAO Yiai;ALISON Ord;TANG Jingru;HU Rongguo;YANG Qijun;WANG Jincao;WANG Benda(Guangxi Key Laboratory of Exploration for Hidden Metallic Ore Deposits,School of Earth Sciences,Guilin University of Technology,Guilin 541004,Guangxi,China;Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources,Guilin University of Technology,Guilin 541004,Guangxi,China;Centre for Exploration Targeting,School of Earth Sciences,University of Western Australia,Perth,WA 6009,Australia;Pinggui Feidie Co.Ltd.,China Nonferrous Metal Mining Group,Hezhou 542800,Guangxi,China)

机构地区：[1]桂林理工大学地球科学学院,广西隐伏金属矿产勘查重点实验室,广西桂林541004 [2]桂林理工大学,有色金属矿产勘查与资源高效利用协同创新中心,广西桂林541004 [3]Centre for Exploration Targeting,School of Earth Sciences,University of Western Australia,Perth,WA 6009,Australia [4]中国有色集团(广西)平桂飞碟股份有限公司,广西贺州542800

出　　处：《大地构造与成矿学》2023年第6期1256-1266,共11页Geotectonica et Metallogenia

基　　金：国家自然科学基金项目(42362008);广西自然科学基金项目(2018GXNSFFA281009、2020GXNSFAA297049);广西科技创新基地建设类项目(桂科ZY21195031)联合资助。

摘　　要：三维地质建模是地质研究的有力工具,断层的三维建模比其他地质体建模具有更大的难度,其中一个主要难题是交切断层切割关系的处理。本文以广西珊瑚矿田为例,探讨了基于地表数据和产状数据的交切断层建模方法,采用地表断层线-剖面断层轨迹-系列断层线-断层面的技术路线进行切割断层建模,采用初始断层面-断后约束条件-交切处理-约束插值的技术路线进行被切割断层的建模,并与其他建模方法的建模效果进行对比和讨论。最终形成了如下建模方法:(1)以旋转法求取部分切割断层的错开部位约束,以平移法求取完全切割断层的错开部位约束;以断层错开部位约束、地表断层线约束及断层面边界约束为控制条件,进行断层面DSI插值,实现断层错动;(2)局部法建模、分段断层线的平移连接及过度追求完全切割关系建模可能分别引起断层面延展可控性差、断面整体偏移误差及沿走向过度延伸问题,与地质事实相悖,故本文优选采用了整体法建模、顺延连接分段断层线及遵从原有切割关系的处理方法,获得了较好的建模效果。3D geological modelling is one of the powerful tools for geological research.The modelling of faults is more complicated than that of other geological bodies,especially in the modelling of a fault partly cutting and offsetting another one.Taking the Shanhu orefield as an example,this paper studies the methods of modelling the intersecting faults based on their surface and occurrence data.The cutting faults are modelled based on the technical route of fault curves on the surface,fault trajectories on cross section,series of curves,and fault surface.The cut faults are modelled based on the route of initial fault surface,post-fault constraints,faults cutting,and interpolation under constraints.In addition,other modelling methods are also tried for comparison and the following understandings are reached:(1)By rotating or translating a cut fault surface from its initial position to the post-fault position followed by the cutting operation,the splitting position constraints of the cut fault are obtained.Discrete smooth interpolation on the fault surface is carried out to realize fault dislocation constrained by the splitting borders,fault curves on the surface,and the fault frame.(2)Modelling from parts of a fault(namely the part method)may result in poor controllability in the extension of segmented fault surfaces;Recovery of the offset fault curves through curve translation will cause overall offset error in the resultant fault surface;Excessive pursuit of fully cutting relation may lead to overextension of faults along their strike.Therefore,this paper adopts the methods of modelling each fault as a whole(namely the overall method),recovering the segmented fault curves by moving and connecting the nodes,and verifying the original cutting relationship,which show reasonable modelling results.It is expected that the understandings could contribute ideas to the modelling of intersecting faults and of strata cut by faults as well.

关 键 词：三维地质建模 交切断层 部分切割 约束插值 珊瑚矿田 

分 类 号：P628[天文地球—地质矿产勘探]