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DRAFT <br />Table 12. Angles of Draw for Mines in Flat-Bedded Sedimentary Rocks with Respect to Lithology of Overburden <br />(Abel and Lee, 1984) <br />Location, Commodity Lithologic Percentages in Angle of References <br /> Overburden Draw <br /> Shale' Sandstone Limestone (degrees)2 <br />Pennsylvania coal. 50 22 28 18.0 Greenwald and others (1937). <br />Do----------------------- 78 13 9 24.0 Maize, Thomas, and Greenwald (1940). <br />Do----------------------- 59 11 30 9.0 Maize and Greenwald (1939). <br />New Mexico coal. 63 37 0 15.0 Abel and Gentry (1978). <br />Great Britain coal. 12 88 0 0.0 English (1940). <br />Do--------------------- 68 32 0 17.0 Sinclair (1950). <br />Do---------------------- 63 29 8 12.0 Do. <br />Do---------------------- 64 36 0 29.0 Briggs and Ferguson (1933). <br />Do--------------------- 51 48 1 16.5 Thorneycroft (1931). <br />New Mexico uranium. 86 14 0 40.0 C. H. Parrish written commun., 1979). <br />California borate a 17 83 0 8.0 (avg.) Obert and Long (1962). <br />Pennsylvania coal. 48 52 0 18.0 Montz and Norris (1930). <br />India coal. 25 75 0 13.0 Kumar and Singh (1973). <br />Do--------------------- 23 77 0 21.0 Do. <br />Do----------------------- 57 43 0 28.0 Do. <br />Do---------------------- 37 63 0 18.0 Do. <br />Do--------------------- 35 65 0 17.0 Do. <br />Do---------------------- 35 65 0 17.0 Do. <br />Do---------------------- 23 77 0 17.0 Do. <br />Do----------------------- 32 68 0 27.0 Do. <br />Illinois coal. 71 17 12 8.5 Herbert and Rutledge (1927). <br />Do----------------------- 57 38 5 0.0 Do. <br />Do---------------------- 85 9 6 34.7 Auchmuty (1931). <br />Arizona copper. 0 0 100 12.0 Trischka(1934)3. <br />'Includes all argillaceous rocks. AAngles measured from vertical. <br />3Fault bounded on all four sides. Therefore, not employed in statistical analysis. <br />Page 39 of 57 <br />