X, A, 4 Pratt: Petroleiim and Residual Bitumens 259 



failed laterally within distances of 10 meters. The openings 

 are all filled with either debris or water, so that they afford 

 little opportunity for the detailed examination of the deposits. 



The bitumen has a schistose appearance and an irregular 

 schistose fracture. Its specific gravity varies from 1.02 to 1.05, 

 depending, perhaps, on the degree of freedom from inorganic 

 impurities. The streak is brownish, somewhat lighter than the 

 color of the bitumen itself. The deposits are at a higher horizon 

 in the Canguinsa clay-tuff than the outcrops at D, and the atti- 

 tude of the beds is again that at outcrops A and B : namely, 

 strike, west-northwest; dip, 20° north-northeast. 



At the point marked H on the map there is a petroleum 

 seep in the Canguinsa tuff-sandstone. Except for the Mount 

 Tabeyta intrusives only Canguinsa rocks are exposed in the 

 neighborhood. The petroleum escapes in very small quantity 

 from cracks and joints, but does not impregnate the rock itself. 

 The strata appear to be about horizontal, but bedding planes 

 are not clearly defined. The seepage is at the base of a hill 

 barely above sea level. On the beach near by is a spring of 

 mineralized water, which emits an odor of hydrogen sulphide. 

 The attempt made during the Spanish regime to exploit the 

 Leyte petroleum deposits centered at the seepage H. There is 

 no evidence now that anything whatever was accomplished in 

 these attempts. 



The petroleum seep at I is in a stream bed which is deeply 

 cut into the Vigo shale. The oil drips from the wall of the 

 creek along the contact between the Vigo shale and diorite. 

 The igneous rock appears to be a lens between beds of steeply 

 dipping shale and from its position might be an intrusion. No 

 evidence of disturbance or metamorphism is to be observed in 

 the shale, however, and the igneous rock may be part of the 

 base upon which the Vigo shale lies instead of an intrusion. 

 On both sides of the diorite exposure, the width of which is 

 a few meters only, the shale is very regular and dips to the 

 north-northeast at an angle of 50°. To the north the Vigo 

 shale is exposed continuously for a distance of at least 800 

 meters, maintaining always the same attitude. About 300 

 meters south of the seep the dip changes in direction to the 

 south-southwest and decreases to about 30°, the strike remain- 

 ing constant. Thus an anticline is indicated in the Vigo shale. 

 Mount Camaro, in which the strata appear to be nearly hori- 

 zontal, marks the crest of this fold, and the petroleum seeps 

 I and J lie on the opposite limbs very near the axis. 



The petroleum at the point marked J comes directly from the 



