Characterization of deep ground geothermal field in Jiahe Coal Mine

Research into the characteristics of geothermal fields is important for the control of heat damage in mines.Based on measured geothermal data of boreholes from -200 m to -1200 m in a Jiahe Coal Mine,we demonstrate non-linear but increasing relations of both geo-temperatures and geothermal gradients with increases depth.Numerically,we fitted the relationship between geo-temperatures and depth,a first-order exponential decay curve,formulated as:T(h) - -4.975 + 23.08 × exp(-h/1736.1 ).