V. C. Illing—The Search for Oil. 295 



2. The supposed Association of Coal and Oil. 



In Pennsylvania, Trinidad, Burma, Borneo, and elsewhere, it has 

 been stated that the oil is found associated with coal or lignite. 

 Those organic-origin theorists who believe that oil hasbeen produced 

 from terrestrial vegetation lay stress on this association of coal and 

 oil, and infer that similar vegetable material entombed within the 

 clays in the lower and more deeply buried strata have undergone 

 a process of destructive distillation resulting in the production of 

 liquid and gaseous hydrocarbons. It would be out of place to 

 discuss the merits or demerits of this purely theoretical question. 

 Suffice it to say that in the majority of the world's oilfields no such 

 association of oil and coal exists, and in the cases noted above the 

 line of demarcation between the oil and the coal-bearing strata is so 

 well denned that the observer is impressed with the distinction between 

 the two formations, rather than with their association. As far as 

 the British Carboniferous strata are concerned, it is difficult to 

 understand of what significance this supposed association can be in 

 favouring the occurrence of underground oil-pools. 



It has been stated by Mr. E. H. C. Craig that the oil-shale group 

 of the Lower Carboniferous of the Lothians represents an old oilfield 

 below the Carboniferous Limestone series with its contained coal- 

 seams. The exact original form of the organic material which con- 

 stitutes the oil-yielding portion of "oil-shale" is not at present 

 known, but neither the chemical, microscopic, nor geological evidence 

 can be brought into agreement with Mr. Craig's hypothesis. As 

 far as the Lower Carboniferous rocks of Britain are concerned, to 

 postulate that the coal-bearing measures will be succeeded at depth 

 by oil-bearing strata on the grounds of a purely theoretical idea of oil 

 formation, is to beg the whole question. The strata below the 

 British Coal-Measures are a distinct and separate formation. The 

 question whether they do or do not contain oil is a matter which 

 must be settled by an examination of their own lithology and 

 contents. The overlying Coal-Measures are only significant as a 

 possible impervious cover rock to prevent the underlying oils from 

 escaping. 



3. The Analogy with the Ahehican Oilfields. 



The two previous sections have really not touched the heart of the 

 whole problem. Oil and gas fields have been discovered without any 

 surface indications whatsoever by the mere process of trial and error, 

 the lucky well of a "wild-cat" venture followed by the inevitable 

 rush of oil prospectors, all eager to share in the gain. Indeed, it may 

 be said that most of the American Palaeozoic oilfields have been 

 discovered in this way. Is it not therefore legitimate to assume that 

 Avhat is true of America may also prove true in this country ? That, 

 if deep wells are drilled so that the lower strata are thoroughly 

 tested, and if in addition the sites of these wells are carefully chosen, 

 it ought to be possible, or even probable, that similar supplies of oil 

 and gas will be found. It is urged that England has not been 

 thoroughly tested by deep wells, and until this is done no one can 

 consider the matter as finally settled. In this section the writer will 



