PETROLEUn. 



BY F. H. OLIPHANT. 



[F. II. Oliphant, geologist and mining engineer; born Uniontown, Pa., August 30, 

 1845; educated at J. R. Moore's academy at Morgantown, Pa; employed two years 

 as rodman for the Pennsylvania railroad ; graduated from the Polytechnic college of 

 Pennsylvania; served for many years as mining engineer for the Pennsj'lvania Gas 

 Coal company and later as geologist for the Standard Oil company; has prepared 

 the U. S. government annual reports on petroleum and natural gas since 1896 and 

 is the recognized American authority on these mineral products.] 



Much speculation and controversy have been aroused 

 among chemists and geologists as to the origin of petroleum, 

 but no complete and satisfactory solution of the problem has 

 yet been presented. Numerous theories have been advanced 

 as to the original source of the carbides and hydrocarbons and 

 their combinations, entering into the form^ation of petroleum, 

 and many scientists of note have a particular theor}^, but there 

 appears little possibility of reaching an agreement in the mat- 

 ter in the near future. Experiments in the laboratory have 

 been made so as to combine the elements artifically and the 

 resultant, in most instances, has been a liquid, which in ap- 

 pearance and composition is very similar to the natural petro- 

 leum. Petroleum has also been produced by the distillation 

 of shales, and there are many upholders of the claim that the 

 formation of petroleum is due to the natural distillation by 

 internal heat of the shales and hydrocarbons found in the 

 earth's crust. Its origin is one of the unsolved problems. 



The various theories advanced by men of science to ac- 

 count for the formation may be in most cases narrowed down 

 to two, each of which has found numerous supporters. These 

 are — first, its physical origin by the distillation of organic 

 matter in the sedimentary strata, either animal or vegetable; 

 second, its chemical origin from inorganic matter or direct 

 production by the decomposition of carbides through the action 

 of steam deepl}^ buried below all sedimentary strata. 



In all of the known fields of the world the occurrence oi 

 petroleum is limited to comparatively small areas. The area 

 of the same strata in which the petroleum is not found invari- 



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