JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. V MARCH 19, 1915 No. 6 



GEOLOGY. — Some relations in origin between coal and petroleum.^ 

 David White, U. S. Geological Survey. ^ 



INTRODUCTION 



It is my purpose this evening to present for your consider- 

 ation some features of the problem of the origin of petroleum 

 and natural gas. The plan followed is to view the question of 

 the origin of petroleum from the standpoint of the origin of 

 coal; to note how some of the fundamental conditions attending 

 the formation of coal and its differentiation in kinds may simi- 

 larly apply to oil; to call attention to some points both of differ- 

 ence and of agreement as to the paleontologic sources of these 

 two great mineral fuels; and to inquire whether certain of their 

 important characters, that are secondary in origin, are not con- 

 ditioned by common causes. 



At the outset it will be assumed that petroleum, as it occurs 

 in a natural state in oil pools in most parts of the world, is the 

 product of the geodynamic alteration of certain types of organic 

 detritus buried in the strata of the outer shell of the earth; that, 

 in other words, it was produced in accordance with the so-called 

 organic theory. It will, however, not be denied that petroleum 

 may be, and in fact has, in some cases, possibly been formed 

 in accordance with the inorganic theory, which, in broad terms, 

 is that petroleum is made chemically from substances of mineral 



^ Presidential address delivered before the Washington Academy of Sciences 

 on January 14, 1915. 



* Published by permission of the Director of the U. S. Geological Survey. 



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