【作者】 王晓东；

【导师】 徐则民；

【作者基本信息】 昆明理工大学 ， 地质工程（专业学位）， 2018， 硕士

【摘要】 研究区位于一级大地构造单元华南褶皱系的西缘,地壳动力学背景十分复杂,主要岩性为可溶性岩石(碳酸盐岩)-白云质灰岩。复杂的地质构造条件及可溶性的地层岩性,导致了该区岩溶发育较为强烈,地质构造对其岩溶发育的控制作用十分明显。大量地表水通过岩溶洼地、漏斗及落水洞下渗,地表水流失较为严重。若不了解该地区的岩溶发育特征,将会对后期工程建设及选址带来一系列的地质问题。因此对个旧锡矿东区背阴山断裂两侧地质构造及岩溶发育规律的研究是一项十分必要且极其重要的任务,并为以后在该地区的工程勘察、设计和建设提供地质学依据。本文通过以五级凹塘尾矿库为几何中心进行详细水文地质工程地质调查,并结合前人研究成果及室内数据分析,运用ARCGIS软件对该区岩溶发育的地质构造背景及其岩溶特征做出了系统的分析;根据地貌特征及洼地、落水洞的空间分布总结出该区岩溶发育的机制和成因模式。最后借助有限元软件ANSYS模拟地下溶洞自下而上不同发育时期的溶洞概念模型,并采用后处理小软件TECPLOT输出计算模型在自重条件下的应力、位移场分布情况。研究表明:研究区以断裂构造和节理构造为主,所有被识别出的断层均为高角度平移断层,具有压剪破坏的典型特征。在地质调查中发现较多露头,本文依据两个不同方面提出了两套构造体系,两个方案中不同之处在于黄泥硐断裂的延伸方向,备选方案中增加了黄梅断裂。并且区内构造控制着其地貌、岩溶及岩溶水的发育过程与运移规律。区内高倾角剪性断裂构造体系为降水入渗及岩溶发育提供了通道与场所,造就了以“垂向为主、水平向为辅”的岩溶发育格局。从落水洞的分布情况、规模以及非典型洼地的地貌特征上,可以推断出研究区内落水洞、漏斗及洼地的形成都是岩溶塌陷这一成因模式所导致的,同时也是形成区内“自下而上”岩溶发育机制的主要原因,最终导致研究区内独特的岩溶地貌特征。通过对区内正在使用的五级凹塘尾矿库为例进行调查,从库区周边落水洞的分布及地貌推断该区极有可能发生过岩溶塌陷。在周边后期形成的落水洞规模较小,渗漏量较小,仅对其进行封堵,工程可安全运行。更多还原

【Abstract】 The study area is located at the western edge of the first-order tectonic unit South China Folds.The crustal dynamics background is very complex.The main lithology is soluble rock(carbonate)-dolomitic limestone.The complicated geological structure conditions and soluble stratum lithology have led to a strong karst development in this area,and the geological structure has a very obvious controlling effect on the karst development.A large number of surface waters infiltrated through karst depressions,funnels,and sinkholes.The loss of surface water was serious.If we do not understand the characteristics of karst development in this area,it will bring a series of geological problems to the construction and site selection in the later period.Therefore,it is a very necessary and extremely important task to study the geological structure and karst development on both sides of the Beiyinshan fault in the eastern part of Gejiu tin mine,and to provide geology basis for future engineering survey,design and construction in the area.In this paper,a detailed hydrogeological engineering geological survey was carried out on the basis of the five-level concave pond tailings reservoir.Combined with previous research results and indoor data analysis,the geology structure background and karst characteristics of karst development in this area were studied systematically using ARCGIS software.Based on the geomorphological features and the spatial distribution of depressions and sinkholes,the mechanism and genetic model of karst development in this area were summarized.Finally,the finite element software ANSYS was used to simulate the underground caverns from the bottom to the top of the development of the concept of caverns,and the post-processing software TECPLOT output model under the conditions of the weight of the stress,displacement field distribution.Research shows:The study area is dominated by faulted structures and jointed structures.All identified faults are high-angle-translating faults with the typical characteristics of compression shear failure.More outcrops were found in geological surveys.Two sets of structural systems were proposed based on two different aspects.The difference between the two schemes was the extension direction of the Huangnidong fault,and the Huangmei fault was added to the alternatives.And the structure of the area controls the development and migration of landform,karst and karst water.The high-angle scissor-fractured tectonic system in the area provides channels and sites for precipitation infiltration and karst development,resulting in a karst development pattern that is “vertical oriented and supplemented horizontally”.From the distribution and size of the sinkholes and the geomorphological features of the atypical depressions,it can be inferred that the formation of sinkholes,funnels,and depressions in the study area was caused by the karst collapse model,and at the same time,it is also the main reason for the formation of "bottom-up" karst development mechanism in the area,which ultimately leads to unique karst geomorphological features in the study area.By investigating the five-level concave pond tailings reservoir currently in use in the area,it is inferred from the distribution and topography of sinkholes around the reservoir area that karst collapse is most likely to occur in the area.The sinkholes formed in the surrounding area are smaller in scale and have a small amount of leakage.They only need to be plugged and the project can be operated safely.更多还原