X, A, 4 Pratt: Petroleum in the Province of Cebu 285 



chance of yielding petroleum could be tested by drilling a series 

 of, say, three 600-meter wells along a northwest-southeast line 

 across the strike of the beds. 



PETROLEUM AT ALEGRIA 



A fairly strong petroleum seep exists at the head of Malbog 

 Creek near the town of Alegria. As early as 1897 a concession 

 was recorded in the name of Smith, Bell & Co., Limited, for a 

 petroleum claim of 150,000 square meters at Talayong, Alegria, 

 and it appears that this claim covers the petroleum seep on Mal- 

 bog Creek. 



Alegria is on the western coast of southern Cebu, and the 

 mouth of Malbog Creek is about 2 kilometers north of the 

 town. The seep is at an elevation of about 365 meters and is 

 about 2.5 kilometers from the coast. Southern Cebu generally 

 is covered with the recent coralline limestone beds; only in 



Fig. 2. Geologic section across strike of beds along Malbog Creek, Alegria. Cebu. n, coralline 

 limestone ; b, volcanic tuff ; c, Miocene shales and sandstones over limestone. 



small areas are the underlying rocks exposed. Fig. 2 repre- 

 sents a section across the strike of the beds and shows the rock 

 succession and structure at the head of Malbog Creek. The 

 petroleum reaches the surface through beds of blue clay or shale 

 and is identical in appearance with the Toledo oil. The oil 

 seeps directly from blue clayey shale in the wall of a ravine, 

 and there is usually a small pool of oil and water at the seep. 

 Blue shale, brown sandy shales, sandstones, and soft light-colored 

 tuff are exposed near the seep with a thickness of about 100 

 meters beneath a capping of perhaps 150 meters of coralline 

 limestone. The tuff is less conspicuous than at Toledo. The 

 general strike is north 20° east; and an anticlinal fold is indi- 

 cated by the dips. In the crest and eastern limb of this fold 

 the beds are standing on edge and appear to be considerably 

 broken up. The first limestone outcrop to the west of the 

 oil seep appears to dip to the east, and must, therefore, pass 

 beneath the shale from which the oil seeps. The presence of a 



