Application of fuzzy analytic hierarchy process in sandstone aquifer water yield property evaluation

Abstract

Accurate evaluation of water yield property is the foundation of mine water inrush risk analysis, and is also an important prerequisite for engineering measures selection. There are many factors or parameters that influence the ability of sandstone aquifers to store and transmit water. Furthermore, the degree to which these parameters affect aquifer productivity is variable depending on the spatial distribution of the parameter in question and other hydrogeological parameters that contribute to water yield property When locates in different position of space, or under different hydrogeological condition, influencing degree from the same factor is different. Five hydrogeological parameters were selected and analyzed to rank areas for potential mine inflow risk based on the hydrogeological units to be intersected by the Yongan Coal Mine. The parameters used in the analysis include aquifer thickness, aquifer lithological association, development of fractures, drilling flushing fluid consumption rates and the coefficient of permeability. Firstly, the distribution of each single factor was separately analyzed, parameters were standardized using the standardization range transform method. In this way, dimension and value range difference could be eliminated, and transformation rule of information data could be studied under the same standard scale. The weight of each factor was determined using improved fuzzy analytic hierarchy process (FAHP). Those factors were then overlaid and analyzed according to the multi-source geo-information fusion principal and to the ability of data process and spatial analysis by GIS. Lastly, aquifer water yield property indexes were calculated and zones were identified. The partition result showed that sandstone aquifer water yield property in Yongan Coal Mine was increased from the northeast to the southwest. This finding is consistent with the hydrogeologic understanding of the study area. The distribution of the parameters used to determine aquifer water yield property in this study is relative but will be helpful for engineering design and construction. These analyses are based on data routinely collected as part of the geological exploration data and on published geological reports. The FAHP methodology employed in this study to evaluate sandstone aquifer productivity is considered to be a novel approach to evaluating mine water inrush potential. • Factors were analyzed and standardized by standardization range transform method. • Factors were overlay analyzed by multi-source geo-information fusion and GIS. • Water yield property distribution is relative, and will be helpful to engineering.