Quantitative Evaluation of Karst Developmental Differences Based on Improved Analytic Hierarchy Process and Multidimensional Extension Matter Element Model

Abstract

In this study, limestone solubility, rock thickness, burial depth, hydrodynamic cycle, and geological tectonic of mine No. 13 in the Pingdingshan coalfield (China) were selected to evaluate the degree of karst development. The weight of each index factor to the karst development was determined by using the improved analytic hierarchy process. The multidimensional extensional matter model was used to determine the degree of karst development of the four mining areas (named 1st to 4th) of the Pingdingshan mine No. 13. The results show that the degree of karst development differs zonally, with 1st and 2nd mining areas presenting the lowest degree of karst development (grade II-IV, for an average quantification value of 3.0) and 4th mining area having the highest degree (grade IV-V, for an average quantification value of 4.7). In the vertical direction, the development degree of the vertical layer L1-L4 karst in the Carboniferous Taiyuan Formation is grade IV-V, with an average quantitative value of 4.5, whereas the layers L5-L7 in the Taiyuan Formation had a III-V grade, with an average quantitative value of 3.75, and the Cambrian limestone grade was II-IV, for an average quantitative value of 2.75, i.e., the development degree of karst gradually decreases from shallow to deep.