Study on the Ground Movement in an Open-Pit Mine in the Case of Combined Surface and Underground Mining

Table 3

Comparison of roof vertical displacement at 15 m and 165 m above No. 9 seam.

Strata vertical displacement	Model I (m)	Model II (m)	Model III (m)
15 m above No. 9 seam	10	6	3.8
165 m above No. 9 seam	7	3.2	2