THE MINING AND QUARRY INDUSTRY I907 45 



ing gas are bottomed in the Trenton, though in many instances 

 secondary contributions are derived from the overlying Utica 

 shale. Elsewhere, as in Oneida and Jefferson counties, these 

 limestones have not afforded any durable supply. 



The next higher horizon of importance is at the base of the 

 Lower Siluric and includes the Medina sandstone and its eastern 

 representative, the Oswego sandstone. The occurrence of pools 

 in this formation is of recent discovery, but they now yield a 

 very large portion of the production. The principal field, opened 

 since 1890, is in Erie county beginning near Buffalo and extend- 

 ing eastward through the towns of Cheektowaga, Amherst, Lan- 

 caster, Clarence, Alden and Newstead. A second field occurs 

 south of Bufi'alo between that city and Jewettville. The wells 

 at Avon and Caledonia, Livingston co., are said to reach the 

 Medina. In the last two years large pools have been encountered 

 in what is regarded as the white Medina sandstone in northern 

 Chautauqua county, notably at Westfield and Silver Creek. The 

 recent discoveries at Pavilion, Genesee co., are likewise reported 

 to be in that formation. 



The remaining formations of the Lower Siluric are made up 

 mostly of shales and limestones. They appear to be relatively 

 poor reservoirs for gas. 



In the Devonic system, practically all of the formations repre- 

 sented in western New York have been found to contain gas at 

 one or more localities. The most prolific, undoubtedly, are the 

 upper members, the Portage and Chemung shales and sand- 

 stones. They are tapped by numerous wells in Allegany, Cat- 

 taraugus and Chautauqua counties. The principal gas supplies 

 are derived from southern Allegany and Cattaraugus counties, 

 from the same fields which yield petroleum. Many of the wells 

 yield both gas and oil, and a part of the gas is consumed locally 

 in operating the oil pumps, while the remainder is run into pipe 

 lines for distribution in the neighboring cities and villages. The 

 original wells put down in the Lake Shore belt of Chautauqua 

 county, at Fredonia, Brocton, Mayville and Ripley seem to have 

 found the gas mainly in the Chemung shales. The deeper wells 

 that were drilled later encountered reservoirs at different 

 horizons below the Chemung, as far down as the Medina. The 

 Marcellus and Onondaga formations of the Devonic are C(~>n- 

 sidered by P)ishop^ to be the sources of the gas at (imvaiuhi. in 

 northern Cattaraugus count v. 



'Oil and ('.as in Smithwi-stcrn New N'ork. N. V. Statt- (iool. lotli An. Rcp't. looi. 

 p- m6. 



