GEOLOGIC RECONNAISSANCE OF SOUTHWESTERN LUZON. 87 



that Banahao was supposed to be in eruption. Arriving at Sariaya it 

 was found that an avalanche of water, mud and stones had descended to 

 the west of the town along the drainage channels which are the natural 

 outlet of the crater, and had covered the road with a layer of debris 

 which in places was more than a meter thick. The water from the 

 avalanche, heavily charged with sediments, reached to the sea, and in its 

 descent changed some of the former channels and swept away a newly con- 

 structed steel bridge on the Sariaya-Candelaria Eoad. As there was 

 nothing which indicated a true eruption, no ascent of the mountain was 

 made, but from the reports of others who followed the avalanche to its 

 source it was learned that a landslide had dammed the chasm through 

 which the crater has its outlet and that the bursting of this obstruction 

 had liberated a lake which had formed therein. Another member of 

 the Bureau of Science ascended the north slope of the mountain a short 

 time previously. He stated that a lake had actually existed in the crater. 

 It seems very probable that the catastrophe recorded as the eruption of 

 1730 was similar in every way to the one which occurred in this year. 

 The velocity of the water which descended enabled " it to carry great 

 bowlders, some of which were fully 2 meters in diameter. The mud in 

 places covered cultivated ground and the force of the moving mass of 

 water and stones uprooted trees and partially destroyed some coconut 

 plantations. The town of Sariaya was located previously further to 

 the west. The inhabitants moved to the present site after the avalanche 

 of 1730 which destroyed most of their homes. 



The flanks of Banahao and Cristobal are covered with a heterogeneous 

 mass of stones and detrital material which has gravitated down the slopes. 

 Deep stream channels cut in this material are seen while driving along 

 the road from Sariaya to the town of Tayabas, and likewise in passing 

 around the north base of these mountains. Solid rocks are exposed in 

 a very few places. At the foot of the mountain slopes this material 

 gradually thins out and volcanic tuff forms the plain. 



Mount Maquiling has been made the subject of a special monograph 

 by Abella. He states that its summit has somewhat the appearance of 

 a crater broken down by erosion. The positions of the peaks which form 

 its summit when seen from the southwest near Santo Tomas, as well as 

 the outline, suggest what was probably once a distinct crater. There are 

 no references to an eruption of Maquiling, but the mountain contains on 

 its slopes and around its base many signs of expiring activity. The hot 

 springs near Los Bahos and the so-called solfataras or hot springs on 

 its flanks may be especially mentioned. The positions of the hot springs 

 and solfataras as recorded by Abella will be seen in the accompanying 



