17. TUSCAROKA TOWNSHIP. F 3 . 363 



( Olive shale, 160' 



„ _„> . , lion sandstone, 2' ) Q , 



Upper Olive shale ^ ,. ? a 



1 Fossil ore, ....... I' > 



and <{ 



Lower ore beds, 



Olive shale, 300 



J Iron sandstone 10' In 



I Hard block ore, 16") 



Lower Olive shale. 



The thickness of the Olive shales is here much greater 

 than in the west of the county, and this greater thickness 

 is accompanied with the development of the lower ore beds 

 which do not exist there. 



Only the Sand-vein ore bed is now worked in Tuscarora 

 township ; but the two lower beds are easily accessible at 

 the river, and could be at once resorted to if the price of 

 the ore were higher. At present about 800 tons a month 

 are sent to market. 



West from the river this ore bed has been opened in numer- 

 ous places, but with one exception all are now ''standing." 

 It is not of uniform quality. In some places as at the new 

 level driven by Mr. R. Cochran a mile west of Millerstown, 

 the soft ore gives place to a hard ferriferous limestone, very 

 exjjensive to mine and containing a high percentage of lime. 

 (For further details see Chapter V.) 



The Onondaga group, (V.) 



Xo natural exposure of these rocks was found in this 

 township. Its nearly vertical beds are concealed by super- 

 ficial soil along Raccoon valley below the level of the open- 

 ings of the ore beds. These openings sometimes begin in 

 the red shale and sometimes in the olive shales underlying- 

 it — the passage beds. But these excavations present no 

 features which have not been already mentioned in this re- 

 port. 



The Lower Helderoerg group, No. VI. 



The rocks of this group crop out forming a low ridge 

 along the middle of Raccoon valley. They differ from 

 themselves in other parts of the county by being less mas- 

 sive. Though no good or complete section is exposed in 

 the township, yet the absence of the massive limestone beds 



