Quantitative Characterization of Overburden Rock Development Pattern in the Goaf at Different Key Stratum Locations Based on DEM

Table 5

The key stratum positions of each experimental scheme.

Scheme		Scheme 1	Scheme 2	Scheme 3
Coal seam	Height mining	6	6	6
Inferior key stratum 1	Thickness	6.7	6.7	6.7
	Thickness from coal seam	9.7	9.7	9.7
Inferior key stratum 2	Thickness	7.2	7.2	—
	Thickness from coal seam	21.9	21.9	—
Inferior key stratum 3	Thickness	11.1	—	—
	Thickness from coal seam	43	—	—
Compound key stratum	Thickness	15.2	—	15.2
	Thickness from coal seam	58.2	—	69.9
Main key stratum	Thickness	11.4	11.4	11.4
	Thickness from coal seam	94.6	54.4	26.1