388 



Report of the State Geologist. 



386 feet for the Salina shales, this gas horizon would be fourteen to twenty- 

 tour feet below the top of the Niagara. Getzville well No. 1 7 struck some gas 

 at 265 feet, which was unquestionably in the Salina shales; but the greater 

 part was found at 474-481 feet. The record indicates Niagara at 3t?l feet 

 or 292 feet from the surface of bed rock. The gas horizon was 113 feet 

 lower and was undoubtedly in the Niagara. 



In connection with this it is interesting to examine the record of the 

 Boston well. Rock-salt was found here 575 feet below the top of the 

 Corniferous or a probable distance of 407 feet below the water-lime. At 

 ?83 feet below the top of the Corniferous, or 615 feet below the water-lime, a 

 vein of water was found, evidently sulphur water, which was very offensive 

 and colored the drill and cables black. As the Salina shales are thickest 

 in the trough containing the deposit of rock-salt, it is apparent that the 

 drill in this well had penetrated some distance into the Niagara lime- 

 stone. The Corniferous limestone and water-lime appear to act as the 

 reservoir for gas in the Zoar field. In three wells quite a show of gas w as 

 found within ten feet below the top of the Corniferous, one had gas at forty- 

 five feet, and two others at seventy and eighty-five feet respectively. Three 

 had gas between 100 and 130 feet, and the famous Kerr well found it at 160 

 feet below the top of the Corniferous. Although a cavity was undoubtedly 

 the reservoir in the last instance, the porous " bull-head " of the water-lime 

 is the most probable receptacle for gas within the formations named. 



A pocket of gas with a flow sufficiently strong to throw the tools out of 

 the well was found in one of the wells at Alden. The reservoir was in the 

 Marcellus and was quickly exhausted. Shallow wells in the Portage rocks 

 furnish small quantities of gas in a few instances which are elsewhere noted. 



Natural Gas Reservoirs. 



The geologic conditions controlling the accumulation of natural gas are 

 not sufficiently understood to furnish reliable data by which a gas well 

 may be located. There are no surface indications of anticlines or other results 

 of deep-seated disturbances which might act to accumulate and hold large 

 quantities of gas. In the Medina sandstone, which is here the principal 

 reservoir, the gas is found w here the rock is soft and porous, but is not found 

 where the rock is hard. Whether this difference in hardness is due to flexure 

 of strata or to some inherent quality of the rock itself, is still to be deter- 

 mined. Good wells are found close by poor ones, and several "dry' 1 wells 



