THE CRATER LAKE OF TAAL VOLCANO ' 



By George W. Heise 



(From the Laboratory of General, Inorganic, and Physical Chemistry, 

 Bureau of Science, Manila) 



ONE PLATE AND ONE TEXT FIGURE 



Previous to 1911 Taal was an active volcano, which had erupt- 

 ed frequently during historic times. The last and, as far as 

 known, the greatest eruption occurred in January, 1911. An area 

 of approximately 230 square kilometers was affected with de- 

 vastating violence, (7) and over 1,300 people were killed. Since 

 that time the volcano has been practically inactive. 



The following description of the volcano was published by 

 Adams (l) about a year before the eruption: 



Taal volcano is situated on an island in Taal or Bombon Lake. The 

 island, on which are found a number of extinct cinder cones and the active 

 crater, has been built near the center of the lake by late volcanic 

 activity. * * * The main crater which is situated near the center is 

 usually referred to as Taal volcano. It is approximately circular in form. 

 The southwestern border of the crater rim rises to an elevation of 320 

 meters, which is the highest point on the island. The lowest points on 

 the rim are about 130 to 150 meters in elevation. The lowest points on 

 the floor of the crater are about on a level with the water of Taal 

 Lake. * * * 



Two lakes lie within this crater. They are usually called the yellow 

 lake and the green lake. During the rainy season there is a third tem- 

 porary red lake. The yellow lake receives the natural drainage of the 

 crater. It appears to be shallow and is hot, but does not boil. The green 

 lake gives off steam from its surface and near its southern border boils 

 violently as if over a vent. A circular crater is located to the south of the 

 green lake. On its floor there are several boiling mud spots from which 

 but little vapor rises. On the south border of the yellow lake there is a 

 cone, called the red cone, because of the color of its crater. It is broken 

 down on the south side and drains around its eastern base into the yellow 

 lake. A vent from which steam issues with great force occurs on its 

 northern outer base. The yellow lake now extends to this vent but formerly 

 was separated from it by a narrow isthmus. There is a remnant of an 

 older, large crater rim which forms a crescentic ridge rising southeast of 

 the yellow lake and curving around to the south of the green lake, passing 

 between the green lake and the crater with the mud spots. 



Plate I, fig. 1, is from a photograph of the crater that was 

 taken before the 1911 eruption. 



1 Received for publication June 9, 1917. 



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