GEOLOGICAL UECONNAISSAXCE OF LEYTE. 347 



Sedimentary rocl's. — Thus far no sedimentary rocks liave been reported 

 as occurring in the cordillera in Leyte, and Abella did not mention any 

 in his description of Biliran Island. However^ according to a seemingly 

 reliable report, there is an occurrence of petroleum on the east coast of 

 Biliran, inland from the sitio Capalis, and it is quite probable that it is 

 in sedimentary rocks. 



The eastern flank of the cordillera is buried for a long distance ])y 

 the alluvial deposits of the northwestern plains. The western flank from 

 Orjnoe to Bayljay descends to the coast. The places where the relations 

 of the sedimentaries may best be studied have not been visited^ although 

 it is certain from a few observations made during this reconnaissance that 

 on the western flank of the Cordillera there is an extensive series of 

 stratifled dejjosits in which limestones are conspicuous. They are more 

 fully discussed in' describing the southwestern district. On the east side 

 of the island similar limestones were seen at only one locality. At 

 Patyuean point and extending inland to the road between Hinunangan 

 and Hinundayan, there is a mountain called Patyuean which consists of 

 massive and thinner bedded limestones which outcrop in conspicuous sea 

 cliflis. They dip towards the south as if they had been given their inclina- 

 tion through a subsidence peripheral to the volcanic center. Mount 

 Cabalian. 



Origin of the Cordillera. — The trend of the Cordillera, as shown on 

 the accompanying sketch map, is about N. 30° W. Abella has expressed 

 his opinion that Biliran Island is due to a volcanic action and that it is 

 a part of a volcanic belt which continues to the southward through Leyte 

 and Panaon and the Eastern Cordillera of Surigao (Mindanao) to point 

 San Agustin with some similar volcanic manifestations, and to the north- 

 ward in the island of Maripipi and others, until it connects with the" 

 active volcano Bulusan in Luzon, being thus situated on one of the vol- 

 canic fractures of the Archipelago. Becker cites this opinion of Abella 

 and also the rather untenable theory of volcanic belts by Koto in his 

 "Geological Structure of the Malay Archipelago" in which is included a 

 structural line from Masbate through Leyte and eastern Mindanao. Es- 

 pecially suggestive are the following remarks by Becker, 



"To my thinking too much effort has been made to show unbrolceii continuity 

 of volcanic zones. Fissures occur far more often in parallel systems than singly 

 and, just as dikes jump from one fissure of such a system to another, so, I 

 think, do the greater volcanic phenomena." 



Much more study will be necessary before the relations of the volcanic 

 zone of Leyte are determined definitely and in the meantime it will be 

 better not to try to extend it too far. In the accompanying map Panaon 

 Island is not included in the trend of the Cordillera, since it is not known 

 to contain any true volcanic phenomena and the rocks seen in the 

 northern end indicate that it is more closely related to the southwestern 

 semi-mountainous district. 



