84 . ADAMS. • • ; ■ ■ • 



and is in part tufaceous. The character of the conglomerate indicates 

 that the older portion, of the Tertiary formation had been elevated and 

 perhaps somewhat folded and subjected to erosion and that materials 

 derived from it contributed to the formation of the conglomerate. Sim- 

 ilar conglomerates were found at three places nearer to Mauban in cuts 

 on the road. At one of these localities basaltic pebbles were mixed with 

 limestone pebbles and at another the matrix was tufaceous. The dip 

 of these exposures was not ascertainable. The district to the east of 

 Lucban lies near the base of Banahao which is an extinct volcano and 

 tuff deposits cover and obscure the structure, of the adjacent upland 

 portion of the eastern cordillera. 



At the locality of the iron deposits near Santa Inez on the Lanatin 

 River, bowlders of limestone are seen in the river and on the hillsides. 

 A massive limestone occurs on the mountain which contains the iron 

 deposit and rests on diorite. About three hours walk up the Lanatin 

 River there is. a mountain exhibiting a conspicuous white face of- lime- 

 stone. To the northwest of San Isidr.o there is a rough limestone hill 

 which is conspicuous when traveling toward Santa Inez. 



It is safe to conclude that the' limestones and associated sedimentaries 

 of the eastern cordillera are Tertiary. Smith has recently referred 

 them to the Miocene on the strength of having found Orbitoides in the 

 limestones. Later, lie has submitted a suite of fossils to a close com- 

 parison with studied collections, and identification of the species points 

 to their being Oligocene. He will soon publish the results of this study. 



In passing it may be well to note that the fossil which McCaskey 

 found near Angat and reported to be a staminate cone of a Lepidodendrid 

 has been studied subsequently by the botanists of the Bureau of Science 

 and the} r pronounce it to be of questionable value and certainly not a 

 Lepidodendrid. 



The upland tying in the district defined by Luisiana, Caventi Majayjay 

 and Pagsanjan and in which the rivers flow in deep gorges and where 

 the Pagsanjan and Botocan falls are located, has a thick deposit of tuff 

 and conglomerates which appear in places to be water laid. This 

 deposit borders and in part «overlies the folded sedimentaries of the 

 eastern cordillera. It was impossible to determine deflniteky whether 

 there is any water-laid tuff on the upland areas, which have an elevation 

 of about 500 meters. The tuff undoubtedly occupies depressions. The 

 youngest beds seem to be of sub-aerial origin. Between Mauban and 

 the Mauban River there is a small hill in the recent alluvial deposits 

 which is composed of water-laid tuff. 



