Distribution characteristics of fluorescent dissolved organic matter in different aquifers of Luotuoshan coal mine

Based on hydrogeological conditions of different aquifers in Luotuoshan coal mine, the distribution characteristics of fluorescent dissolved organic matters in Ordovician limestone water were investigated through detection and analysis of three-dimensional fluorescence spectrum (3DEEM), total organic carbon (TOC), UV₂₅₄ and inorganic anions of natural organic matters in water of different aquifers. The results showed that the concentrations of TOC and UV₂₅₄ decreases with the increase of aquifer depth. The concentrations of TOC and UV₂₅₄ in other aquifers were 2~3.3 times and 2.4~4.7 times higher than those in Ordovician limestone. SUVA was 3.28, 2.27, 2.24 and 1.96 in surface water, Quaternary water, sandstone aquifer water and Ordovician limestone water. There were five finger-print areas in 3DEEM of surface water and Quaternary water, and there were not tyrosine, hydrophobic acid and marine humic acids in Ordovician water. Aromatic protein Ⅱ was produced when organic matter reacted, and which made the FI of aromatic proteinⅡbeing higher in Ordovician limestone water than that in other aquifers. The concentration of TOC decreased from 0.27 mg/L to 0.22 mg/L along the direction of groundwater flow in Ordovician limestone water, and the variation of aromatic proteinⅡ was opposite to TOC. According 3DEEM fluorescence spectrum, dissolved organic matter is stable in Ordovician limestone water in Luotuoshan mine, which is obviously characteristic ion to discriminate bursting source of Ordovician water.