TENNESSEE 123 



I II 



Feet Feet 



9. Fireclay and shale ... 67 



10. Coal bed 



11. Sandstone 12 



giving in the second, which reaches to the bottom, a thickness of about 

 350 feet— an increase of about 125 feet in comparison with Tracy City 

 and of about 150 feet in comparison with Franklin county, but nearly 

 100 feet less than is shown by Mr Hayes's sections 8 or 10 miles farther 

 northeast.* 



Crossing now to the eastern portion of the Cumberland plateau, sepa- 

 rated from the main area by the Sequatchie valley and known as 

 " Waldens ridge," one finds little difficulty in following the section north- 

 ward from the Alabama line, though the thickening of the measures 

 causes perplexity at times. This area embraces portions of Marion, 

 Hamilton, Sequatchie, Bledsoe, Rhea, and Cumberland ; but the name 

 is applied to the east portion of the plateau as far as the northern 

 boundary of Tennessee, so that there may be included also portions of 

 Roane, Morgan, Anderson, and Campbell counties. In its southern por- 

 tion, Waldens ridge is sometimes spoken of as " Raccoon mountain," the 

 name which it bears in Alabama. 



The Etna mines are in southeast Marion at about 2 miles north from 

 the Alabama line, about 10 miles west from Chattanooga, and somewhat 

 farther east from the western side of the Sequatchie valley. The section 

 extends from the Lower Carboniferous up to the great sandstone midway 

 between the Bonair and the Rockcastle. It was studied nearly 50 }^ears 

 ago by Professor Safford and almost 30 years later by Professor Colton. 

 The two sections are presented together, number 1 being that by 

 Professor Safford : 



I II 



Feet. Inches. Feet. Inches 



1. Sandstone 75 73 



2. Shale 48 32 Shaly sandstone 



3. Walker's coal bed 4 4 



4. Shale with coal bed 30 to 40 46 



5. Coal bed, Slate vein 5 to 6 6 



6. Shale 44 44 



7. Kelly coal bed 2 to 3 2 to 5 



8. Fireclay 1 to 2 1 6 



9. Main conglomerate 75 82 Upper conglomerate 



10. Coal bed Thin 3 



* J. M. Safford : Geology of Tennessee, pp. 355, 369, 370, 372, 373, 374, 376, 379, 392, 393. 

 C W. Hayes: U. S. Geol. Survey folios, Kingston, 1892; Chattanooga, 1892; Pikeville, 1895; 

 McMinnville. 



