Bulletin 100 Table 5

Table 5 In situ stress measurements in Illinois. See figure 13.
	Principal stress orientation	Method of measurement	Reference
1	N 59 E	Earthquake focal solution	Herrmann 1979
2	N 76 E	Strain gauge in coal mine	Y.P. Chugh 1984 (pers. comm.)
3	N 76 W	Strain gauge in coal mine	Y.P. Chugh 1984 (pers. comm.)
4	N 90 E	Earthquake focal solution	Y.P. Chugh 1984 (pers. comm.)
5	N 87 E	Strain gauge in coal mine	Blevins 1982
6	N 83 E	Earthquake focal solution	Stauder and Nuttli 1970
7	N 73 E	Borehole breakout measurement	Dart 1985
8	N 29 E	Borehole breakout measurement	Dart 1985
9	N 72 W	Borehole breakout measurement	Dart 1985
10	N 67 W	Borehole breakout measurement	Dart 1985
11	N 81 E	Borehole breakout measurement	Dart 1985
12	N 50 E	Borehole breakout measurement	Dart 1985
13	N 56 E	Borehole breakout measurement	Dart 1985
14	N 88 E	Borehole breakout measurement	Dart 1985
15	N 89 E	Borehole breakout measurement	Dart 1985
16	N 72 E	Borehole breakout measurement	Dart 1985
17	N 62 E	Hydrofracturing in boreholes	Haimson 1974 (exact location not specified)
18	N 41 E	Overcoring in coal mine	Hanna et al. 1985
19	N 72 E	Overcoring in tunnel	Shuri and Kelsey 1984
20	N 48 E	Hydrofracturing in boreholes	Haimson and Doe 1983
21	N 90 E	Overcoring in coal mine	Ingram and Melinda 1988
22	N 78 E	Overcoring in coal mine	Ingram and Melinda 1988