366 The Philippine Journal of Science 1913 



it may be concluded that the sandstone reservoirs are of small 

 lateral extent and, consequently, that wells could be spaced 

 closely without affecting each other. This being the case, the 

 structurally favorable area over which the Bacau stage could 

 be reached by drilling is large enough to make the total possible 

 production of commercial importance. In addition to the pos- 

 sibilities of the Bacau stage there is the chance, which has been 

 discussed, of obtaining oil at other horizons in the Vigo shale. 



As evidence which bears somewhat on the question of ob- 

 taining petroleum on Bondoc Peninsula, it may be worth while 

 to consider, briefly, the results of exploration for petroleum in 

 other oriental fields. The general geology of the two important 

 productive fields in the Orient, the Echigo field in Japan and 

 the Moera Enim field in Sumatra, is similar to that of Bondoc 

 Peninsula (compare Tables I, II, and III). 



There are productive fields in Sarawak and in the eastern 

 part of Borneo, but in British North Borneo the attempts to 

 obtain petroleum have been unsuccessful. Although Borneo is 

 adjacent to the Philippines, very little information is available 

 concerning its economic geology and nothing is known of the 

 geology of its petroleum resources. 



In Formosa (Taiwan) which is also adjacent to the Philip- 

 pines, only a small production, 6,200 barrels in 1908, 2 * is re- 

 corded, although many shallow wells have been drilled. One 

 of the few deep wells in the Byritsu Field on Formosa is said 

 to yield a good flow of oil, and there is a possibility that with 

 deeper drilling the Formosa petroleum fields will assume greater 

 importance. 



A well drilled in 1896 on Cebu Island in the Philippines, is 

 said to have reached a depth of 300 meters ; while it encountered 

 considerable petroleum, it did not yield a satisfactory flow. The 

 exploration was suspended before completion, because of the 

 outbreak of an insurrection, and it has never been resumed. 

 While the general geology of the two regions is similar, the local 

 conditions at the site of the well in Cebu are different from 

 those in Bondoc Peninsula. The drilling site at Toledo, Cebu, 

 is located on the outcrop of the petroleum-bearing strata, and 

 is within a few kilometers of the basal igneous complex upon 

 the flank of which the beds lie, inclined at a high angle. 



M Fukotome, K., Mineral Resources of Formosa (1910), 13. The Mineral 

 Resources of the United States for 1911 reports 8,304 barrels of oil from 

 Formosa in 1908 and 1,638 in 1911. 



