MAWORTH: the COFFEVVILLK KXI'LOSION. 69 



THICKNESS OF 



STRATA. TOTAL DEPTH. 



28 feet .... Blue sandstone 426 feet. 



6 .... Black shale 432 



1 9 .... Light shale 45 1 



10 .... Blue sandy shale 461 



20 .... Shale 48 1 



10 .... Brown shale 491 



32 .... Shale 523 



15 .... Gre}' sandstone, gas-bearing 538 



42 .... Shale 580 



20 .... Light colored sandstone, gas-bearing 600 



It is quite evident that an ordinary explosion due to the oxida- 

 tion of the gas could not have occurred on account of the impossi- 

 bility of getting the requisite amount of oxygen mixed with the gas 

 while it was below the surface. Neither is it probable that the 

 phenomenon was seismic in character, for it is confined to too 

 narrow limits. On the other hand at least one similar occurrence 

 is known in the gas field of Indiana* near Kokomo in which a 

 fissure was formed in the solid limestone from which natural gas 

 escaped with explosive violence and caught fire from a burning log 

 heap near by. 



A short consideration of the possibilities of the case may not be 

 wholly without interest. We will assume that the gas pressure 

 was 300 pounds to the square inch. We know that in some of the 

 Coffeyville wells it was more. The specific gravity of the materials 

 near the surface is about 2.75. Now let us suppose that in some 

 way a leak from the depth below occurred, possibly by the drilling 

 of the well, but quite as likely from natural causes. Suppose this 

 gas was conducted upwards to near the surface where it was per- 

 mitted to spread laterally in a thin seam or opening between the 

 layers of shale. It should be remembered that a layer of gas one- 

 fourth or one-half inch thick Avould exert a pressure as great as 

 though it were much thicker. The leak may have been very slow 

 so that months, or even 3'ears, were occupied in the accumulation. 

 If the gas sheet covered an area 300 feet square the upward pressure 

 would be equal to nearly four billion pounds, or nearly two million 

 tons. The character of the eruption indicates that the material 

 came from near the surface, probably from less than twenty feet. 

 If we consider the gas pressure and the specific gravity as above 

 mentioned we would have the pressure per square foot equal to 

 43,200 pounds, and the weight of a cubic foot of earth equal to 172 

 pounds. It would therefore require a depth of a little over 250 feet 



* The writer is indebted to Mr. Win. Moore, of Kokomo. foi' his information on this 

 subject. It is understood that an account of the e.xplosion has been published by 

 Prof. Jordan, State Gas Inspector, but exact reference is not available just now. 



