232 AKNUAL REPORT SMITHSONIAN INSTITUTION, 1942 



future and considered as possibilities of accumulation in each or any 

 of these unexplored layers of geology, reveals a correspondingly large 

 undiscovered future oil reserve and the enormous geologic effort 

 necessary to find it. 



Most petroleum geologists began working in two dimensions — 

 length and breadth at the surface. Later, as more wells were drilled, 

 a third dimension, depth, was added. They now find themselves 

 thinking and applying a fourth dimension to their work — geologic 

 time — and as with the other dimensions, its addition to their kit 

 gives the horizon yet another push outward. 



The only really new approach to the problem of oil discovery that 

 has developed in many years is the recent use of earth-chemistry or 

 geochemistry. Its approach differs from geological and geophysical 

 systems because it is a direct method, dependent only on the presence 

 of oil regardless of the kind of trap, whereas the older methods are 

 all concerned solely with the search for favorable structure, in which 

 it is hoped oil may be found. 



Many claims have been made for geochemical methods and if they 

 were all realized it would be but a short time until all of the oil fields 

 in the world were found. However, there are many geological objec- 

 tions to its philosophy, and so far there have been very few or no oil 

 fields found as the sole result of its application. Until it proves 

 itself to be successful, it will probably continue to be regarded with 

 a considerable amount of restraint as an instrument of discovery. 

 We should not forget, however, that much highly intelligent experi- 

 mentation and research is going on continually in this field, and that 

 we may well see the day when it, or some modification of the present 

 method, is a generally accepted tool of oil exploration. 



A development in petroleum geology, which I believe is significant, 

 is of a different nature since it deals with the geologist rather than 

 with his thinking. It is the trend in the oil industry to place geo- 

 logically trained and experienced men in executive and managerial 

 positions. It is coming on at an ever-accelerating pace and in nearly 

 every month that passes we hear reports of promotions and changes 

 in which geologists are advanced into positions of authority outside 

 their normal field of activity. As Pratt ^ has so well put it, the 

 geologist now " permeates the industry," and he has come in " like a 

 metasomatic phenomenon in ore deposits in which the invading solu- 

 tion completely changes the internal character without changing the 

 outward appearance." 



This trend has far-reaching consequences. Although in the early 

 days the petroleum geologist was practically limited in his application 

 of geology to discovery by his ability to make the nontechnical execu- 



• Pratt, Wallace, Geology In the petroleum industry. Bull, Amer. Assoc. PetroL Geol., 

 vol. 24, pp. 1209-1213, July 1940. 



