敦化市东山硅藻土矿区水文地质特征研究及涌水量预测

发布时间：2018-04-20 06:13

本文选题：东山硅藻土矿区 + GMS软件　；参考：《成都理工大学》2017年硕士论文

【摘要】：东山硅藻土矿区地处敦化-密山断裂带控制的新生代断陷盆地,盆地内为新近系中新统土门子组(N_1t)地层,岩性主要由砂岩、硅藻土、含硅藻粘土及玄武岩组成。硅藻土矿主要赋存于N_1t地层,该地层固结程度较差,地质和水文地质条件复杂,富水性较好,矿层开采难度较大,准确合理的预测涌水量为未来该矿区矿山安全开采、排水方案设计等提供理论依据,对指导同类硅藻土矿山开采具有重要的科学意义。论文以水文地质学、工程地质学、地下水动力学等理论为基础,综合应用水文地质调查、抽水试验以及室内试验等技术手段,并采用“大井法”、“水均衡法”和“数值模拟”等方法预测东山硅藻土矿区矿坑涌水量。获得研究成果如下:(1)硅藻土矿层作为隔水层分布于全区,近水平产出,局部与顶板含水层直接接触。K_1号矿层的主要顶板充水含水层为N_1t~3,含水层厚度大、富水性中等,地下水类型为碎屑岩类裂隙孔隙水;K_2号矿层的主要顶板充水含水层为N_1t~8,含水层厚度分布不均、富水性弱,地下水类型为玄武岩孔洞裂隙水。(2)结合研究区水文地质特征,构建含(隔)水层与矿层垂向空间结构模型分别为Qh~(al)松散岩类含水层+Qp_1j、Qp_3n和N_1t~(10+8)玄武岩含水层+N_1t~7(K_2号矿层)隔水层+N_1t~(6+4)玄武岩含水层+N_1t~3砂岩含水层+N_1t~2(K_1号矿层)隔水层+N_1t~1砂砾岩含水层组合结构。(3)依据研究区地质、水文地质资料建立了三维地质模型和水文地质概念模型;以地质模型和水文地质概念模型为基础,建立了能够描述和反映研究区地下水流动特征的数学模型,再运用GMS中MODFLOW模块构建了研究区三维地下水数值模型,随后运用研究区35个水位观测孔数据对模型进行稳定流识别与校正,最后运用J_(03)和JG_(03)抽水试验观测数据对模型进行非稳定流识别与校正。实际水位观测值与模型计算水位值拟合较好,表明本次模拟选取的水文参数,边界条件和源汇项概化都很合理,所建模型可靠,可用于矿区涌水量预测。(4)基于识别和验证后的模型,采用GMS中Well(抽水井)模块在开采区设置6口抽水井进行疏降水,预测雨季矿坑最大涌水量为7800m~3/d;通过“大井法”和“水均衡法”计算出的涌水量分别为8044m~3/d和7714m~3/d,与采用模型预测的最大涌水量之间差距分别为3.13%和1.10%,三种方法所得结果较接近,相互印证,进一步的验证了数学模型的可靠性。
[Abstract]:The Dongshan diatomite mine is located in the Cenozoic faulted basin controlled by the Dunhua-Mishan fault zone. The basin is composed of sandstone, diatomite, diatom clay and basalt. The diatomite deposit mainly occurs in Nji 1t formation, which has poor consolidation degree, complex geological and hydrogeological conditions, good water enrichment and difficulty in mining ore bed. The accurate and reasonable prediction of water inflow is the safe mining of the mine in the future. The design of drainage scheme is of great scientific significance for guiding diatomite mining. Based on the theories of hydrogeology, engineering geology, groundwater dynamics and so on, the paper applies the techniques of hydrogeological investigation, pumping test and laboratory test, and adopts "large well method". The methods of water balance and numerical simulation are used to predict the water inflow of Dongshan diatomite mine. The results of the study are as follows: (1) diatomite ore beds are distributed in the whole area as a water-separating layer, producing near level. The main roof filling aquifer of the substratum. K1 is directly in contact with the roof aquifer. The main roof filling aquifer is N1t / 3, and the aquifer is thick and medium water-rich. The groundwater type is the main roof water-filled aquifer of clastic rock fissures and pore water, the aquifer is N1t ~ (8), the thickness of aquifer is uneven, the water-rich is weak, and the type of groundwater is basalt pore and fissure water. 2) combined with the hydrogeological characteristics of the study area. The model of vertical spatial structure of water-bearing (separated) aquifer and ore bed is Qhlangalao) Qp1j-Qp3n and N_1t~(10 _ 8) Qp1J / Qp3n and N_1t~(10 _ 8) basalt aquifer, N_1t~7(K_2) water-isolated layer, N_1t~(6 _ 4) basalt aquifer, N_1t~3 sandstone aquifer, N_1t~2(K_1 ore deposit, respectively, Qp1J / Qp3n and N_1t~(10 _ 8). N_1t~1 sand gravel aquifer assemblage structure. 3) according to the geology of the study area, Based on the geological model and hydrogeological conceptual model, a mathematical model which can describe and reflect the characteristics of groundwater flow in the study area is established. The 3D groundwater numerical model of the study area is constructed by using the MODFLOW module in GMS, and then the steady flow is identified and corrected by using the data of 35 water level observation holes in the study area. Finally, the unsteady flow is identified and corrected by using the observation data of the pumping test. The actual water level observed value fits well with the calculated water level value of the model, which indicates that the hydrological parameters, boundary conditions and source and sink terms selected by this simulation are all reasonable, and the model is reliable. Based on the identified and verified model, well (pumping well) module in GMS is used to set up 6 pumping wells in the mining area for thinning and dewatering. The predicted maximum inflow of mine in rainy season is 7800mg / d, and the water inflow calculated by "large well method" and "water balance method" is 8044m~3/d and 7714mg / d, respectively, and the difference between the maximum water inflow predicted by the model and that predicted by the model is 3.13% and 1.10%, respectively. The results obtained by the three methods are close to each other. Mutual verification further verifies the reliability of the mathematical model.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD742;P641.46

【参考文献】