Effect of Mining Thickness on Overburden Movement and Underground Pressure Characteristics for Extrathick Coal Seam by Sublevel Caving with High Bottom Cutting Height

Table 4

Overlying strata convergence in different thick coal seams.

Distance from coal seam roof (m)	9 m		15 m		25 m
	Final settlement (mm)	Subsidence coefficient	Final settlement (mm)	Subsidence coefficient	Final settlement (mm)	Subsidence coefficient
10	8847	0.983	14790	0.986	24675	0.987
30	8478	0.942	14235	0.949	23950	0.958
50	7767	0.863	13695	0.913	23325	0.933
90	6876	0.764	13290	0.886	22900	0.916
130	5952	0.661	11970	0.798	20700	0.828
180	5337	0.593	10095	0.673	18575	0.743
240	4689	0.521	8565	0.571	15525	0.621
300	2961	0.329	5235	0.349	13225	0.529
360	1908	0.212	3630	0.242	7800	0.312