REPLY TO DISCUSSION BY C. W. WASHBURNE 



ON "NOTES ON PRINCIPLES OF OIL 



ACCUMULATION" 



A. W. McCOY 

 Bartlesville, Okla. 



In reply to Mr. Washburne's discussion of this paper, each of 

 his main points will be answered briefly in the following paragraphs. 



The first criticism offered is that as to the origin of liquid 

 petroleum from solid hydrocarbon waxes (commonly called kerogen) 

 in the shale. The original paper states that "no appreciable 

 amount of heat was developed, " implying that the amount of heat 

 developed was in no way comparable to the necessary distillation 

 temperature for those hydrocarbons. The heat developed was not 

 great enough to melt a thin coat of paraffin which had been placed 

 around the bulging zone of the cylinders. 



Moreover, the paper does not state that pressure was the direct 

 cause for this change, but definitely says that pressure alone can 

 cause no change in the material. It suggests that this change can 

 take place in regions of differential movement, and that such zones 

 are the only areas where liquid oil is likely to be made. Field 

 observations indicate that such a condition exists, but a discussion 

 of the point would necessarily be too long for this short statement. 

 Pressure and release of pressure are essential for differential move- 

 ment. The latter action is probably the real cause for any chemical 

 change, whether resulting directly from developed heat or other- 

 wise. 



Mr. Washburne's suggestion that the chemical action of forming 

 liquid petroleum from solid waxes is an exothermic one, and when 

 once started will generate heat to carry on the action, neither 

 agrees with the work of Engler and Hoefer, nor with the evidence 

 gathered by the author from laboratory distillations. Before this 



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