270 I. C. WHITE PETROLEUM *FIELDS OF NORTHEASTERN MEXICO 



in order to force themselves upward to the surface from depths of 1,500 

 to "2,500 feet through fractures in the overlying shaly beds out of their 

 source in the Tamasopa limestones. Messrs. Doheny and Canfield also 

 go a step further with their generalization, and say that no productive 

 oil territory is to be expected in regions where there are basaltic hills 

 but no seepages. While the writer fully concurs in these views as to the 

 interpretation of active seepages, he also believes that productive oil 

 pools may also be found at a considerable distance from the basaltic hills 

 for the following reasons : The existence of the seepages is due to frac- 

 tures and faults made through the overlying shales by the up thrust of 

 igneous dikes, cones, laccolites, and other types of volcanic energy which 

 at the same time tilted the underlying sedimentaries so that their con- 

 tained petroleum could segregate into pools of commercial value around 

 the several centers of disturbance, just as the anticlinal, monoclinal, or 

 quaquaversal disturbances of the sedimentary beds in the Appalachian 

 and other oil fields of the United States have served the same purpose. 

 In such a wide region as that covered by the seepages shown on the map, 

 it would be almost impossible that no other disturbance of the sedimen- 

 taries could have taken place except in the immediate regions of volcanic 

 activity. Of course, in such cases of anticlinal folding distant from 

 hills or dikes of igneous rocks no important fractures of the shales over- 

 lying the oil horizons would be made, and hence no seepages of oil could 

 appear on the surface, although large pools of it might exist in the gently 

 folded Tamasopa limestones 2,000 feet or more below. It is true that 

 owing to paucity of rock exposures in the dense jungles of the tropics, 

 it may be almost impossible to find the evidence of these minor lines of 

 folding in the sedimentaries, but, nevertheless, this is no reason that 

 such may not exist, and therefore the writer considers it highly probable 

 that some productive oil pools may exist far removed from the presence 

 of either oil seepages or volcanic dikes, hills, or laccolites, since the same 

 great petroliferous limestones (Tamasopa) underlie the entire Gulf coast 

 region and only require to be tilted at a small angle in order to make 

 possible the accumulation of commercial pools of oil along such axes of 

 disturbance or folding. 



The Question of Salt Water 



Ever since the Dos Bocas gusher ran wild and began to belch up such 

 enormous volumes of hot salt water that the estimates thereof run into 

 millions of barrels daily, many oil experts have reasoned that a like fate 

 of "going to hot salt water suddenly" awaits every other gusher oil well 

 that exists or may hereafter be developed in the Mexican fields. This 

 conclusion, however, does not appear to rest upon sufficient evidence to 

 justify such an important generalization. In the first place, it is the 



