砂体沉积微相分析与水文地质特征研究——以五阳煤矿研究区3#煤顶板为例

Analysis of Sandbody Sedimentary Microfacies and its Hydrogeology Characteristics: Taking the Seam Roof of WuYang's 3# Coal Mine for Example

为了进一步探明五阳煤矿在开采过程中受到矿井突水威胁的实际情况.本文从水源、通道和强度三个因素方面综合分析五阳煤矿钻孔资料,研究岩性的粒度变化,岩石的颗粒、杂基、胶结物各个组分的构成关系,各个岩相的组合方式,以及测井曲线的形状和组合形态;结合相关古生物特征,综合相关地震相研究研究岩相的沉积构造、颜色;进一步通过野外地质调查研究,结合相关沉积相分析,参考区域地质图和区域地层简表.分析研究的结果表明,可以判定K8砂岩形成于上三角洲平原沉积,且基本不受潮汐影响;可将其细分为分流河道微相和天然堤微相,从而最终确定3#煤顶部的沉积微相分布.研究区水源主要为奥陶系灰岩含水层,石炭-二叠系砂岩裂隙-岩溶水以及第四系孔隙水.结论:五阳煤矿可采煤层3#的直接充水含水层为顶板砂岩裂隙含水层,且不同区域构造类型不一,应注意含水层之间的水力联系,重点研究断层和陷落柱的影响.

In order to map out the actual situation of mine water inrush threat in Wu Yang coal mine in the process of mining,we analyzed in this paper the drilling data of Wuyang coal mine from three factors： water source,passage and strength.The lithology column and well logging curve were studied by the analysis of the lithology granularity,the constitution relations among the components of grains,matrix and cement.In terms of lithofacies combination,the combination shape and form of well logging curve,the study showed that the K8 sandstone formed in the delta plain sedimentary environment,and basically was not affected by tides.With more specific analysis of lithofacies,combined with relevant paleontological characteristics,sedimentary structure,color and the relevant seismic facies study,K8 was further subdivided into distributary channel microfacies and natural levee microfacies.Thus the sedimentary microfacies distribution of 3 # coal roof was eventually determined.The water in the study area was mainly consisted of the ordovician limestone aquifer,permo-carboniferous sandstone fissure water and quaternary pore water.The conclusion was that the direct water filling main minable seam 3 #coal seam is roof sandstone fracture aquifer,with different structure types in different areas.