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GEOLOGY OF ERIE COUNTY 



In Erie county the Tichenor limestone varies from a foot to 

 four feet in thickness- It occurs in layers which vary in number 

 at different outcrops. At Windom it consists of two layers, each 

 a foot thick. At Springbrook it comprises six layers totaling 

 three feet. At Bullis Road it is four feet thick and is made up of 

 ten layers. 



F. Houghton, Photo. 



Fig. 10. Tichenor limestone at Town Line Road, north branch of 

 Smoke's creek. 



It is highly pyritiferous and in weathering shows iron stains. 

 At Springbrook the bottom surface of its lowest layer is coated 

 with a half inch of iron pyrite. It is impregnated with petroleum 

 which fills all cavities and oozes out from its surfaces. It is 

 semi-crystalline in structure and refractory under the hammer. 

 It is durable as a building stone but unsightly because of its iron 

 stain, but it is used in a small way locally for bridge abutments 

 and cellar walls. 



It is highly fossiliferous. Its bulk is mainly coarsel}' 

 comminuted fragments of crinoids, corals and shells, and enclosed 

 in this matrix are entire fossils of many species. Favosite corals 

 abound, many being a foot or more in diameter. The rock is 



