Quantitative Evaluation for the Threat Degree of a Thermal Reservoir to Deep Coal Mining

Table 16

Composition of matrix .

Index factor	Threat level
	Safe (I)	Low threat (II)	Medium threat (III)	Relatively high threat (IV)	High threat (V)
	0.4084	0.6858	0.9631	1.2405	1.5178
	1270.66	1332.31	1393.96	1455.61	1517.26
	1.0349	1.1661	1.2972	1.4284	1.5595
	21.8961	28.7631	35.6300	42.4970	49.3639
	0.0132	0.5887	1.1641	1.7396	2.3150
	1.1120	1.2343	1.3566	1.4789	1.6012
	48.7721	51.3561	53.9400	56.5240	59.1079
	-177.8983	-128.7312	-79.5640	-30.3969	18.7703