Mechanism of Strain Burst by Laboratory and Numerical Analysis

Table 2

Microcomponents of the samples by X-ray diffraction analysis.

Sample	Mineral components and contents (%)							Clay mineral content (%)
	Quartz	K-feldspar	Plagioclase	Calcspar	Dolomite	Siderite	Pyrite
Granite	27.0	37.0	31.0	-	-	-	-	5.0
A-sandstone (a)	57.7	8.7	13.8	0.5	-	-	1.5	17.8
A-sandstone (b)	23.4	4.6	3.0	22.5	5.1	20	0.9	20.5

A-sandstone means the argillaceous sandstone. (a) and (b) are two samples used for the X-ray diffraction analysis, and the first one is lighter while the other one is darker.