262 GEOLOGY OF OHIO. 



terraces are beautifully defined, and rise to more than fifty feet above the 

 stream. This deposit extends to at least seventy feet below the present 

 bed at Bellair, as has been proved by borings. How much deejjer the 

 original bed of the river lies can not be ascertained from any records of 

 borings now accessible. 



The rock formations of the country belong altog^her to the epoch of 

 the Coal Measures, and exhibit portions of the Lower Barren Group and 

 Upper Coal Group of Rogers. An approximate section of the western 

 part is as follows : 



FT. IN. 



1. Debris, with fragmeDts of limestone 15 



2. Sandstone 45 



3. CoalNo.13 1 6 



4. Fire-clay 8 



5. Black shale 7 



6. Sandstone 60 



7. CoalNo.12 1-2 



8. Fire-clay 10 



9. Sandstone and shale 20-35 



10. Coal No. 11 (Waynesburg) 1-6 



11. Sandstone and shale 50 



12. Limestone 6 



13. Sandstone 45 



14. CoalNo.lO 4 



15. Fire-clay 3 



16. Sandstone 35 



17. CoalNo.9 2 6 



18. Fire-clay 2 



19. Limestone 45 



20. Black shale 3 



21. Coal No. 8 (Pittsburgh) 4 2 



22. Fire-clay 3 



23. Shales 0-12 



24. Limestone 4-30 



25. Sandstone 110 



26. Shale 10 



27. Criuoidal limestone 4 o 



In the eastern portion of the county the section difiers materially be- 

 tween Coals Nos. 8 and 10. As obtained th-ere it is as follows : 



FT. IN. 



14. CoalNo.lO 3 o 



15. Fire-clay 2 



16. Sandstone 35 o 



"17. Coal No. 9 2 fi 



18. Fire-clay 1 



19. Limestone 7p 



20. Shale 3 



