122 STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 



coal, too thin to be worked, was found by Washburne in the north- 

 east part of the Bighorn Basin near the IMontana Hne.^^^ 

 ' Calvert reports that, in the Electric coal field, Park County, 

 Montana, the Kootenai is 577 feet thick and with same general 

 structure as that of the Cloverly. The Fuson, 230 feet, consists of 

 variegated shales, limestones and thin sandstones ; the Lakota, 249 

 feet, has a coal bed, one foot thick and underlying a conglomerate 

 sandstone; but it seems to be local. In the Livingston coal field of 

 the same county, the Kootenai is 540 feet thick and apparently has 

 no coal. In the Crazy ^Mountains coal field of Meagher County, 

 north from Park, Stone found the Kootenai only 235 feet thick with 

 variegated sandstones in the upper half and variegated shales in the 

 lower half. The lowest of the sandstones is coarse and has layers 

 of conglomerate ; it overlies one foot of black shale ; no coal is re- 

 ported. ^-'^ 



Calvert'-^ found 512 feet of Kootenai -in the Lewistown coal 

 field of Fergus County, where the upper part is variegated shale 

 with two massive, cross-bedded sandstones, 8 and 25 feet thick ; 

 the lower part, 147 feet, is coarse sandstone, locally conglomerate, 

 with sandy shale. The workable coals of the Kootenai in this field 

 are in the lower portion at 60 to- 90 feet above the base and under- 

 lie a massive cross-bedded sandstone. In some districts only one 

 seam is present but in others there are several. The seams are 

 distinctly lenses, separated by unproductive spaces. The thickness 

 seldom exceeds 5 feet and ordinarily the coal is divided into benches 

 by partings of shale or bone. The roof is shale or sandstone and 

 the floor is shale or clay ; in many cases a bench-bone is at top or 

 bottom of the coal. A dull, lusterless coal, resembling cannel, was 

 seen at several places but especially in the Mace mine, where it 

 occurs as lenses within the coal, the largest being 200 feet long. 

 The coal is accepted as bituminous, but the percentage of ash varies 

 greatly. 



The Great Falls coal field in northern Cascade County, west 



i^^E. G. Woodruff, Bull. 341, p. 203; C. W. Wasliburne, the same, p. 170; 

 N. H. Darton, Bull. Geol. Soc. Amer., Vol. 19, pp. 447-449. 



120 W. R. Calvert, Bull. 47I--E, PP- 34, 53. 58; R. W. Stone, Bull. 341, p. 80. 



1-1 W. R. Calvert, Bull. 341, pp. no, 113, 117, 119; Bull. 390, pp. 56, 61, 

 72, 74- 



