韩城矿区地质构造的运动学与动力学解析

发布时间：2018-02-02 13:25

本文关键词： 地质构造运动学动力学构造成因模式韩城矿区　出处：《西安科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：煤炭工业作为能源和基础产业,支持和保障着陕西省国民经济和社会的发展。处于“渭北黑腰带”东部的韩城矿区开采历史悠久,是陕西省重要的煤炭生产基地,为陕西省甚至全国的经济发展做出了巨大贡献。但韩城矿区地质构造十分复杂,成为制约矿区煤炭安全高效开采的重要地质因素。开展对韩城矿区地质构造的运动学和动力学研究,揭示地质构造的成因机制,有助于全面深入地认识韩城矿区地质构造的发育展布规律,为矿区安全高效开采提供地质依据。同时,也是对煤田构造及构造控煤研究的进一步深化,具有一定的理论意义和实用参考价值。通过本文研究工作,取得了以下主要结论。(1)分别采用沉降史分析法和平衡剖面法,计算了矿区的升降运动量、收缩和伸展运动量。计算结果表明,晚石炭世～中三叠世矿区地层累计沉降量1300m以上,晚三叠世～中新世不均匀抬升量600m以上;印支期南北向挤压收缩率为1.4%,燕山期由SE向NW挤压收缩率达11.52%,喜山期由NW向SE拉张伸展率2.7%以上。揭示了 SN向挤压收缩率南大北小;NW向收缩率东大西小;NW向收缩率大于SN向收缩率的运动学特征。(2)韩城矿区在印支期受到近南北向的挤压应力,挤压应力具有“南强北弱”的特点;燕山期受到自SE向NW的挤压应力,具有“东强西弱”特点,且在北区平面剪应力集中;喜山期区域构造应力场由挤压转变为拉张,向SE方向的拉张伸展作用一直持续到现代,且在继续向北西方向发展。(3)韩城矿区在印支期形成近东西向褶皱和逆断层以及由NE向和NW向剪裂面构成的共轭剪节理系,构造变形具有“南强北弱”特点;燕山期形成矿区构造的基本格局,表现为NE向褶皱和逆断层、近东西向与近南北向剪裂面构成的共轭剪节理系,构造变形具有“东强西弱”的规律,且在北区发育更多层滑构造和构造煤;喜山期区内普遍发育以正断层及其组合为代表的伸展构造,表现出“东强西弱”和“南强北弱”的规律。三期构造相互限制、叠加和改造,使得矿区地质构造错综复杂。
[Abstract]:The coal industry, as an energy and basic industry, supports and guarantees the development of the national economy and society in Shaanxi Province. Hancheng mining area in the east of Weibei Black Belt has a long history of mining. It is an important coal production base in Shaanxi Province, which has made great contribution to the economic development of Shaanxi Province and even the whole country. However, the geological structure of Hancheng mining area is very complex. It has become an important geological factor restricting the safe and efficient mining of coal in mining area. The kinematics and dynamics of geological structure in Hancheng mining area are studied to reveal the formation mechanism of geological structure. It is helpful to fully and deeply understand the development and distribution of geological structure in Hancheng mining area, and provide geological basis for safe and efficient mining in the mining area. At the same time, it is also a further deepening of the study on coal field structure and structural coal control. It has certain theoretical significance and practical reference value. Through the research work of this paper, the following main conclusions are obtained: 1) the subsidence history analysis method and the balanced section method are used to calculate the ascending and descending movement quantity of the mining area respectively. The results show that the accumulative subsidence of late Carboniferous ~ Miocene mining area is more than 1300m, and the uneven uplift amount of late Triassic ~ Miocene is more than 600m. During the Indosinian period, the compression contraction rate was 1.4% in the South-North direction, and 11.52% in the Yanshanian period from SE to NW. The extensional rate of NW to SE is more than 2.7% in the Himalayan period, which reveals that the compression shrinkage in SN direction is small in the north and south. The contraction rate of NW is large and small in the east and west. The kinematic characteristics of NW direction shrinkage ratio is larger than SN direction shrinkage ratio. (2) the Hancheng mining area is subjected to the extrusion stress in the Indosinian period, and the extrusion stress has the characteristics of "the south is strong and the north is weak". The Yanshanian period is subjected to compression stress from SE to NW, which is characterized by "east strong and weak west", and is concentrated in plane shear stress in the northern region. During the Himalayan period, the tectonic stress field changed from compression to extension, and the extensional extension to SE direction lasted until the modern times. In the Hancheng mining area, nearly east-west fold and reverse faults and conjugate shear joints composed of NE and NW shear face were formed in the Indosinian period. The tectonic deformation is characterized by "the south is strong and the north is weak". The basic structure pattern of Yanshanian mining area is characterized by NE-trending fold and reverse fault, conjugate shear joint system of near east-west direction and near south-north direction shear fracture surface. The tectonic deformation has the law of "east strong west weak". Moreover, more layer slip structures and tectonic coals are developed in the northern region. Extensional structures, represented by normal faults and their assemblages, are generally developed in the Himalayan area, showing the law of "east strong strong west weak" and "south strong strong north weak". The third stage structures restrict each other, superimpose and reconstruct each other. The geological structure of the mining area is complicated.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.11;P548

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