206 white: relations between coal and petroLeum 



eastern Kansas, the oils in the Pennsylvanian rocks appear to 

 range from 29° to 39° Baume, averaging about 31° to 34° in 

 gravity. In this field there appears to be slight evidence of 

 betterment of the rank of the oil in passing southward, as is to 

 be expected in view of the southward improvement in the rank of 

 the coals, though the data examined are not really sufficient. 



It is interesting to note that the oils of the "Trenton" in 

 eastern Indiana and northwestern Ohio, as well as those in the 

 Silurian and Devonian of eastern Michigan and western Canada, 

 though of gravities to be expected in regions where the nearest 

 coals in younger formations are of bituminous rank, are not of 

 so high rank as the oils in Carboniferous rocks in the regions 

 of greater alteration nearer the eastern border of the Appa- 

 lachian oil fields. This circumstance I believe to be due to the 

 diminution of the intensity of the post-Paleozoic thrusts in this 

 region, while the rocks of Trenton age and other pre-Carbonifer- 

 ous formations have not been subjected to dynamic stresses so 

 vigorous as those endured by the Carboniferous rocks in West 

 Virginia and western Pennsylvania. It is, however, to be noted 

 that the ''Trenton" oils are of higher gravity than the Carbonif- 

 erous oils in the bituminous coal regions of Indiana and Illinois 

 and it is almost certain that they are of higher rank than would 

 be found in overlying Pennsylvanian rocks were the latter present 

 in the "Trenton" region. It is also seen that the oils of the 

 "Clinton" s^nd districts of Ohio are but slightly better in gravity 

 than those of the Carboniferous nearest on the east. 



In the great Appalachian oil field, the petroleums found in 

 the Carboniferous sands range, in general, from gravities of 

 38° to 44° on the western, to gravities of 46° to 48° Baume on the 

 eastern margin of the productive field. The best oils, showing 

 gravities of 49° and 50° or even 52° are found along or near the 

 eastern margin of the field, in northern West Virginia, western 

 Pennsylvania and western New York.'^ 



1^ The gravities of the oils in this region vary somewhat from point to point 

 and from sand to sand, the rank of an oil in a Devonian sand being locally infe- 

 rior to that in the overlying Carboniferous, though, in general, it appears that, 

 even in this region, the sands in the older or underlying formations contain oils 

 of highest rank. 



