DISCOVERY 



241 



and, further, that it will be a lesson to those who 

 anticipate similar schemes for other parts of the 

 British Isles in the future. 



We cannot leave the survey of English oil prospects 

 without reference to the oil-shale industry, which is 

 certainly rather a different proposition from that 

 referred to above. It is a well-known fact that at 

 certain horizons in the stratigraphical series, car- 

 bonaceous rocks occur from which, by artificial dis- 

 tillation, a form of petroleum may be obtained ; but 

 at present only one large field in this country has been 

 worked for any length of time with success, and that 

 is situate in the Midlothian Carboniferous field of 

 Central Scotland. These shales have yielded over 

 forty gallons of oil per ton in the past — though this 

 is by no means a phenomenal amount for good oil 

 shale — whilst the by-production of ammonium sulphate 

 to the amount of 50 lb. and over per ton has been 

 a contributing factor of no small importance to the 

 success of these operations. 



There seems to be no reason why the production 

 of shale oil from this centre should not be a stan- 

 dard industry for many years to come, as the de- 

 posits are by no means e.xhausted. On the contrary, 

 further extensions of the field should be possible 

 within the confines of the main tectonic trough in 

 which the Calciferous Sandstone series lie in this 

 region. While, on account of certain complexities of 

 structure, there may be an element of risk in putting 

 down trial boreholes for the location of deeper seams, 

 it would not be anything like so hazardous an under- 

 taking as that to which the country gave almost tacit 

 assent last year in Derbyshire. 



Another field has come under the public eye of late, 

 and one which promises to afford interesting results ; 

 namely, the Norfolk oil-shale field. Very little in- 

 formation has been forthcoming in connection with 

 the development here, though the reader is referred 

 to Dr. Forbes Leslie's paper, read before the Institute 

 of Petroleum Technologists in January 1917, for 

 general details. Geologically, this subterranean oc- 

 currence in Norfolk is of great interest, though in the 

 present writer's opinion the structures are difficult of 

 elucidation without adequate borehole data, and Dr. 

 Forbes Leslie's explanations thereof do not always 

 seem to him conclusive. Apart from that, it is cer- 

 tainly a possible field, and as such, a potential asset 

 to our home oil industry. 



Other occurrences of oil shale, such as those of 

 Kimcridge in Dorset, the so-called " Kirneridge Coal," 

 have been worked in the past with intermittent success. 

 The Kirneridge shale yielded at times as much as 70 

 gallons of crude oil per ton, with a rather small amount 

 of by-products. The extent of tlie shales, however, 

 is extremely limited, and any mining of tliem would 



necessitate working thin and probably discontinuous 

 seams over a wide area, a process which is seldom a 

 profitable one. 



For the rest, small oil-pools probably will be met 

 with from time to time in various parts of the country 

 during boring operations, particularly in Carboni- 

 ferous formations ; but the public would be well 

 advised to receive such reports with the scepticisn. 

 they deserve, and to reahse once and for all that oil, 

 in sufficient quantity to make it a commercial proposi- 

 tion, is certainly not one of the many blessings which 

 Nature has seen fit to bestow upon us. 



Crossing the Channel into the main continent of 

 Eurasia, the oUfields can be divided into two main 

 groups for present purposes : those in which we have 

 financial interest, and those in which we have or may 

 have both financial and administrative interests. 

 With the former group we are not here concerned ; it 

 includes the important fields in Russia, Roumania, 

 and Galicia, and so long as political and economic 

 conditions allow, constitutes an open market from 

 which we, in common with other countries, may draw 

 large quantities of oil for home consumption. The other 

 group includes our own colonies in Asia and the East 

 Indies, and our interests in Persia and Mesopotamia. 



In the countries of Burma and Assam occur probably 

 the most \'aluable oil resources that we possess, the 

 Upper Burma fields being already famous for their 

 oil-production, while the Assam fields only await 

 development on a large scale. The comparatively 

 recent prominence of the Burma fields is largely due 

 to the progress made in overcoming difficulties of 

 transport, which formerly necessitated conveyance of 

 the crude oil for over 300 miles via the Irrawaddy River 

 to Rangoon. With the installation of pipelines, the 

 production has naturally increased and further deve- 

 lopments may confidently be expected, particularly 

 in the Minbu and Yenangyat districts. The Assam 

 fields have yet to be fully prospMjcted, but no doubt 

 exists as to the great possibilities of the Tertiary 

 deposits of the Brahmaputra and Surma basins. The 

 petroliferous beds are here often associated with coal 

 seams, and are located along a bolt of country stretching 

 from Chittagong approximately N.N.E. for a distance 

 of over 800 miles. At present the Digboi field, near 

 Debrugarh, on the Brahmaputra, is the best-known 

 region actually working ; but the results of geological 

 survey at various points along this belt have shown 

 most favourable indications for the location of new 

 sites, though in some places the structures are exceed- 

 ingly complex, owing to the disturbed character of 

 the strata. 



Of the Malay Archipelago, British North Borneo, 

 Brunei, Labuan Island, Sarawak, and British New 

 Guinea (Papua), all show indications of oil to a greater 



