阳泉新景煤矿矿井构造特征及其形成机制

发布时间：2018-04-05 21:08

本文选题：构造特征　切入点：叠加褶皱　出处：《中国矿业大学》2015年硕士论文

【摘要】：本文在矿井地质资料系统收集、整理和分析的基础上,结合区域地质构造背景演化和野外节理分期配套的古构造应力场分析,深刻揭示了矿井构造发育、展布、组合特征及不同期次构造的相互叠加与改造规律,并运用构造趋势面分析定量评价了矿井构造发育特征;通过构造煤、构造岩变形特征,煤镜质组反射率有限应变分析等,揭示了新景煤矿的不同期次构造发育的应力-应变环境、矿井构造的演化史及其形成机制,取得以下主要研究成果和认识:(1)新景煤矿构造变形整体较弱,以NNE~NE向的褶皱为主,多期叠加褶皱普遍发育,形成了穹状隆起、盆形构造和马鞍状构造,控制着矿井的主要形态;断裂构造不发育,以小断层成群出现为主,3号煤层断层走向较为分散,但以NE向和NW向为主,15号煤层以NNE向集中发育。断层在剖面上形成阶梯状组合以及小型地堑地垒等。(2)构建了煤层底板等高线趋势面数学模型,通过对3煤和15煤煤层底板等高线1-4次趋势面及残差图分析,3号煤层和15号煤层整体形态较为接近,均反映了一NE高而SW低的单斜构造,且倾角较小,很好的反映了矿井地层总体产状特征。残差图则较为清晰的反映了褶皱发育的形态,向斜为负、背斜为正,对穹窿构造和盆形构造显示较为明显,而对鞍状构造的指示作用不显著,其中三次残差图中0线较好的显示了矿井构造向背斜相间、整体以NNE~NE向展布为主要特征的构造形态。(3)研究区发育高倾角共轭剪节理系,节理走向以NEE向最为发育,其次为近EW向及NNW~NE向,反映了研究区内多期次、不同方向的构造应力场的作用。在对节理组之间的交切关系及力学性质观察和分析的基础上,揭示了应力场特征及其演化规律。研究区煤系形成后主要经历了3期构造应力场作用,分别为印支期最大主应力σ1平均方向为4°,主要形成近EW向的宽缓小型褶皱;燕山期构造运动最为强烈,区内最大主应力σ1平均方向为318°,形成矿井内普遍发育的NNE~NE向大型宽缓褶皱、小型逆断层及NW向小型正断层,该期对矿井构造格架的形成起到了关键性作用;喜马拉雅期运动仍较为强烈,区内最大主应力σ1平均方向为48°,形成了矿井内NW向的宽缓褶皱及较为发育的NW~NWW向逆断层。矿井煤层较为复杂的褶皱展布和组合形态是三期构造应力场共同作用的结果。(4)阐释了新景煤矿构造主要形成于中低温-低温的脆性变形环境,将构造煤形成的应力-应变环境分为挤压和拉张脆性碎裂变形环境、剪切脆性及脆韧性变形环境和剪切与挤压韧性变形环境三类;煤镜质组反射率光性组构较好的反映了区域上近NW~SE向的挤压应力作用。
[Abstract]:Based on the collection, arrangement and analysis of mine geological data system, combined with the analysis of paleotectonic stress field of regional geological tectonic background evolution and field joint stages, this paper deeply reveals the development and distribution of mine structures.The combination characteristics and the law of mutual superposition and transformation of different periods of structures are used to quantitatively evaluate the characteristics of mine structure development by using structural trend surface analysis, and through the analysis of structural coal, deformation characteristics of tectonic rocks, finite strain analysis of coal vitrinite reflectance, etc.The stress-strain environment, evolution history and formation mechanism of the structures in Xinjing coal mine are revealed. The main research results and understanding are as follows: the tectonic deformation of Xinjing coal mine is weak, mainly of NNE~NE fold.The multi-stage superimposed folds are generally developed, forming the domelike uplift, basin structure and saddle structure, which control the main shape of the mine, the fault structure is not developed, the main fault is small fault group, the strike of the No. 3 coal seam fault is scattered,However, NE and NW are dominant, and coal seam No. 15 is concentrated in NNE.A mathematical model of the isobaric trend surface of coal seam floor is established by the formation of ladder assemblage on the section of the fault and the formation of small graben barrier, etc.Based on the analysis of 1-4 trend surfaces and residual maps of the contour line of floor of No. 3 and 15 coal seams, it is found that the overall morphology of No. 3 and No. 15 coal seams is relatively close, which reflects a monocline structure with high NE and low SW, and a smaller dip angle.A good reflection of the overall occurrence of the mine strata characteristics.The residual plan clearly reflects the shape of fold development, the syncline is negative, the anticline is positive, it is obvious to the dome structure and basin structure, but not to the saddle structure.In the third residual diagram, line 0 shows well the structure of the anticline, which is characterized mainly by the distribution of NNE~NE direction.) the high dip conjugate shear joint system is developed in the study area, and the most developed joint is in the direction of NEE.Secondly, the near EW and NNW~NE directions reflect the action of tectonic stress field in different directions and multiple periods in the study area.Based on the observation and analysis of the intersecting relation and mechanical properties of joints, the characteristics of stress field and its evolution are revealed.After the formation of coal measures in the study area, the tectonic stress field was mainly experienced in three periods. The maximum principal stress 蟽 1 in Indosinian period was 4 掳in average direction, which mainly formed a wide, gentle and small fold near EW direction, and the Yanshanian tectonic movement was the strongest.The Himalayan movement is still strong, the average direction of maximum principal stress 蟽 1 in the area is 48 掳, which forms a wide and slow fold in NW direction and a relatively developed NW~NWW reverse fault in the mine.The complex fold distribution and assemblage form of coal seam is the result of the interaction of tectonic stress field in the third stage. It is explained that the structure of Xinjing coal mine is mainly formed in the brittle deformation environment of middle low temperature and low temperature.The stress-strain environment formed by tectonic coal is divided into three types: extruding and tensioning brittle fracture deformation environment, shearing brittleness and brittle ductile deformation environment and shearing and extruding ductile deformation environment.The optical fabric of the vitrinite reflects the compressive stress near the NW~SE direction in the region.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD82;TD163.1

【引证文献】