Assessment of Chemical Effects on Wellbore Stability in Transition Shale Formation

Table 1

Mineral composition and content.

Sample	Mineral composition (%)
	Quartz	Plagioclase	Calcite	Dolomite	Siderite	Clay mineral
1	22.8	12.8	9.5	14	1.9	39
2	19.7	8.7	8.8	12.6	19.7	30.5
3	44.9	23.5	0.0	5.9	3.9	21.8
4	41.6	10.6	1.3	3.7	0.9	41.9
5	34.3	7.4	0.6	7.2	0.9	49.6
6	39.2	9.3	0.4	5.1	0.8	45.2