小庄井田煤层地质特征及影响因素研究

Study on the Influence Factors and Geological Features of Coal Seam in Xiaozhuang Field

小庄井田位于陕西省咸阳市彬长矿区中部,煤炭资源丰富。探讨该地区的聚煤规律,对煤炭勘探开采具有现实的指导意义。本文应用岩石学、构造地质学、沉积学、煤田地质学等理论和分析方法,对小庄井田延安组含煤地层的沉积特征、煤层展布特征、古地形、同沉积构造等进行详细分析。研究结果表明,小庄井田延安组主要以曲流河沉积环境为主,聚煤模式为河流沼泽聚煤。延安组主要有4煤、4-1煤及少量的3煤,其中4煤为主采煤层。受古地形和同沉积基底沉降的影响,4-6、224钻孔附近古隆起区为无煤区;213钻孔附近为低洼区,沉积空间较大,为煤的聚集提供了良好的场所;煤层厚度最大,达35.22m,为井田的聚煤中心,由聚煤中心向四周煤层厚度逐渐变薄。

Xiaozhuang minefield is located in the middle of Binchang mining area,in Xianyang,Shaanxi,which has rich coal resources.It is realistically significant for exploration and mining to discuss the regulation of coal accumulation.This paper applied theories and analytical methods such as petrology,structural geology,sedimentology,and coal geology to a detailed analysis of the sedimentary characteristics,coal seam distribution,paleo topography,and co-sedimentary structure of the coal-bearing strata of Yan'an formation in Xiaozhuang minefield.The study indicated that Yan'an formation in Xiaozhuang minefield is mainly dominated by the depositional environment of meandering rivers,and the model of coal-accumulating is rivers and marshes.There are 4#,4-1 and a little 3#coal in Yan'an formation,and 4#coal is the main coal mining.Due to the influence of paleo topography and sedimentation,the ancient uplifts which is near boreholes of the 4-6 and 224 are coal-free,and the boreholes of the 213 are low-lying areas with large deposition space,which provides a good place for coal accumulation.The thickness of the coal seam is up to 35.22 m,which is the coal gathering center in minefield,and the thickness of the coal seam gradually decreases from the coal-gathering center.