RECONNAISSANCE OF SOUTHEASTERN LUZON. 469 



it the deposits are tinged and in part vividly colored with red oxide of iron. 

 Fantastic forms of the silicious material may be seen simulating coral growth. 

 Foreign substances which have accumulated near the hot waters are coated with 

 the sinter. 



Lanot Mineral Spring. — On the beach at the barrio of Lanot on the 

 west coast of San Miguel Bay there is a spring which contains iron 

 and is highly charged with carbon dioxide gas. The waters are con- 

 sidered to be of medicinal value and the place is a local health resort. 



In addition to the springs above mentioned, attention may be called 

 to the hot springs near Manito, across the bay from Legaspi. One of 

 these on the beach is covered at high tide, but at low water it sends 

 up a small column of steam which can sometimes be seen from passing 

 steamships. There are other hot waters and a number of mineral 

 springs in the region of the cordillera, but they are considered of little 

 importance at present. 



CABAMUAN PENINSULA. 



This area lias been but partially studied. The eastern end consists 

 principally of Tertiaiy sedimentaries which have been folded and much, 

 disturbed from their original positions. Bugged topography is produced 

 by the upturned limestones which have weathered into steep hills. 

 The rocks have been subjected to strong dynamic action, are consider- 

 ably metamorphosed, and in places exliibit a schistose stntcture. 



Exposures of schist are found near Sabang at the head of Lagonoy 

 Gulf and the .streams bring down schistose andesites from the higher 

 hills. There are somewhat altered schistose andesites near Balocbaloc 

 Point on San Miguel Bay. The higher mountains of the peninsula 

 near Saddle Peak have not been studied, but it is inferred from stream 

 gravels that they are andesites. 



Dynamic action seems to have been strongest along the southern 

 border of the peninsula, since the sediments near the Caramuan River 

 and on some of the islands near its mouth are less metamorphosed 

 than on the opposite coast. It is probable that the formations of 

 Caramuan Peninsula received a thrust from tlie Pacific side which 

 folded the sedimentaries and produced the schistose stnxcture in the 

 rocks. 



In discussing the physiography of this district attention was called 

 to the drowned appearance of the north coast of the peninsula and 

 to the fact that the 30-fathom line indicates a submarine shelf lying 

 off shore. In explaining the origin of the placer deposit of the Paracale- 

 jVIambuIao district, additional proof of a submei'genee was deduced. 



The only economic deposits reported as occun'ing on the peninsula 

 are coal and copper. Coal near Mount Hanopol, Mhich has been pros- 

 ])eoted l)v means of a tunnel, was examined and found to be a thin 



