洛河组含水层垂向差异性研究及保水采煤意义.

In order to explore the hydrogeological conditions of the Cretaceous Luohe Formation in Binchang mining area, this paper proposed the Luohe Formation’s refined exploration concepts from the perspective of water-preserved coal mining, gave a comprehensive water-rich index method which can be used to evaluate the vertical water-richness of confined aquifers. The Luohe Formation was layered according to vertical water-richness. Luohe formation’s vertical hy-drogeological conditions and characteristics, hydraulic connection between the vertical aquifers of Luohe formation before and after mining, and the significance of water-preserved coal mining of the lower aquifer of Luohe formation were studied. Calculation method of water-rich index is given as follows:the indexes of lithology, thickness and porosity are assigned, and their weights are 0.3, 0.4, and 0.3 respectively;the value of water-rich index（fi） can be obtained by the cumulative multiplication of values of indexes and weights;then, the comprehensive water-rich index of each layer can be obtained using the following formula Fi=0.5fi+0.15fi-1+0.1fi-2+0.15fi+1+0.1fi+2. Grading standards of comprehensive water-rich index for aquifers in Luohe Formation are given:F<0.003 289 is aquiclude, 0.003 289≤F<0.012 339 is weak water-rich, 0.012 339≤F<0.015 504 is medium water-rich, and F≥0.015 504 is strong waterrich. According to the comprehensive water-rich index, the Luohe Formation of T1 and T2 drilling in Gaojiabu mine field were divided into the upper, the middle and the lower aquifers vertically. The results shows that:（1）the comprehensive water-rich index method could be used to evaluate the vertical water-richness of a confined aquifer, and it is simple and easy to use. （2）Mudstone formations were found in Luohe aquifer in some areas, but have not yet formed an aquiclude in the area. （3）The lower aquifer of Luohe formation could not only slow down the destruction of the upper and the middle aquifers structure from water flowing fractured zone, but also prevent the water inflow which was from the upper and the middle aquifers from entering working face. It is beneficial to protecting the groundwater of Luohe aquifer during coal mining;（4）During mining the first face of Gaojiabu mine, the controlling height of coal mining was used to protect the groundwater of Luohe aquifer, and the groundwater level in the middle and upper aquifers of the Luohe formation decreased by 26.71-43.06 m. Through the analysis of groundwater volume, water level, and water quality, it have achieved the goals of protecting the aquifer’s structure of Luohe formation and safely mining the deep coal seam. [ABSTRACT FROM AUTHOR]