关键词:
岩溶陷落柱
顾北煤矿
发育特征
成因
摘要:
作为华北煤田发育的独特构造,部分岩溶陷落柱具有较强的富水性及导水能力,这在很大程度上限制了煤炭开采作业的顺利进行。为确保顾北煤矿的安全生产,本文以顾北煤矿北一采区2#岩溶陷落柱为研究对象,基于已收集的研究区工程、水文地质资料,结合钻探物探结果,分析了2#陷落柱的发育特征及工程、水文地质特征,讨论了陷落柱发育的主要成因。研究表明:2#陷落柱的陷落带及影响带在平面上呈近圆形,而在垂直剖面上则展现出上部狭窄、下部宽大的圆锥形特征;2#陷落柱垂向导水性强、水平渗透性弱,影响带在二叠系煤系地层弱富水,太灰及以下地层弱至极强富水,陷落带强至极强富水。2#陷落柱呈NE向的带状分布,与大断裂构造向一致,明显受控于构造特征。寒武系岩层于加里东–海西期经历了长期的剥蚀风化,大范围岩溶在此期间形成,这也表明岩溶陷落柱的发育具备了前期物质和空间基础;研究区断裂构造带发育有大量裂隙,裂隙之间相互连通形成裂隙网络,为地下水的径流与排泄提供了良好的通道;研究区良好的地下水动力条件对陷落柱的分布与形成同样具有重要作用。陷落柱发育特征及其成因的研究为煤矿井下开采工作的顺利开展提供了指导方向,具有较高的现实意义与科研价值。As a unique structure of the North China Coalfield, some karst collapse columns have strong water-richness and water-conducting capacity, which largely limits the smooth progress of coal mining operations. In order to ensure the safe production of Gubei Coal Mine, this paper takes the 2# collapse column in the North 1st mining area of Gubei coal mine as the target of study, based on the collected engineering and hydrogeological data of the research area, combined with the results of drilling and physical exploration, analyses the development characteristics and engineering and hydrogeological features of the 2# collapse column, and discusses the main causes of the development of collapse columns. The study shows that: the trap zone and influence zone of 2# collapse column are subcircular in plan, while in the vertical section, it exhibits a conical feature that is narrow in the upper part and wide in the lower part;2# collapse column has strong vertical hydraulic conductivity and weak horizontal permeability, the influence zone is weakly water-rich in Permian coal strata, weakly to very strongly water-rich in Taihui and the following strata, and strongly to very strongly water-rich in the trap zone. The 2# collapse column is banded in the NE orientation, which is in line with the large rupture structure orientation and is obviously controlled by the structure features;the Cambrian rock strata experienced long-term denudation and weathering during the Caledonian-Hercynian per