274 The Philippine Journal of Science 1915 



mixture of bitumen and clay-tuff from outcrops L and M yields 

 about 175 liters of crude oil containing 10 per cent of gasoline, 

 36 per cent of kerosene, and 52 per cent of heavy oils. The 

 heavy oils and residue contain about 20 per cent of paraffin. 

 Therefore the mixture from outcrops L and M yields nearly 

 twice the volume of oil that the Scotch shales yield, and the oil 

 obtained contains a higher proportion of the lighter, more valu- 

 able constituents. From the best shale in New South Wales 

 more than 600 liters of crude oil per ton are obtained, but the 

 average yield is much less than this figure. It might be found 

 practicable to enrich the bitumen mixture from outcrops L and 

 M in Leyte by additions of the pure bitumens from the other 

 outcrops and so obtain more crude oil upon distillation. The 

 distillation products from the rock asphalt at N are similar in 

 character to those from the mixture at L and M, and although 

 most of the rock asphalt contains too little bitumen to justify 

 distillation, parts of it are much richer than the mixture from 

 L and M. One sample from N, for instance, yielded almost 62 

 per cent of bitumen. Gasoline, kerosene, and heavy oils, what- 

 ever their source, would find a ready market in the Philippines. 

 It is concluded, then, that the natural bitumens in Leyte can 

 be profitably utilized if they are developed in quantity. 



SUGGESTIONS FOR EXPLORATION 



The possibility of obtaining petroleum commercially in Leyte 

 should be investigated further. My observations do not enable 

 me to indicate the most favorable drilling sites nor even to 

 state that the chances of success are great enough to warrant 

 drilling. The venture might not prove attractive to private 

 capital, but considering the immense industrial importance of 

 petroleum to the Philippines, the Government might be justified 

 in an attempt at development. 



This recommendation that the Government undertake to ex- 

 plore petroleum deposits has already been made in the case of 

 the Tayabas field. In view of the later investigation of the 

 Leyte region a question arises as to which territory offers the 

 better chance of success, which should be explored first, and 

 whether or not both fields should be tested. The answers to these 

 questions must await further geologic study. 



It may be explained that petroleum is commonly found in 

 porous beds, where it is retained by cover and floor of close- 

 grained impervious beds after having been driven to the highest 

 points to which it has access by the buoying-up effect of the 



