THE VOLCANO ASO AND ITS LARGE CALDERA 525 



occupy crater basins; the greatest dimensions of the former are 14.5 

 by 7 miles, and of the latter 13 by 4.5 miles. ^ 



Deception Island, in the South Shetland group, contains an oval 

 crateriform harbor 6 miles long and 4 miles wide. 



The well-known craters of the Hawaiian Islands are representa- 

 tive of the caldera type. The largest of them is Haleakala, which is 

 of irregular shape and covers 16 square miles. It has 2 arms, each of 

 which is about 6 miles long and 2 miles wide.^ Mohokea caldera on 

 the side of Mauna Loa measures about 6 by 5 miles. ^ 



In Galapagos Islands there are 5 large craters on Albemarle 

 Island. The largest is at the south end and has a length of about 12 

 and a width of about 6 miles. The others vary in size down to a 

 length of 3 miles or less.'* 



The Central American lakes, ^ Atitlan and Amatitlan in Guate- 

 mala, and Ilopango in San Salvador, are 3 lakes whose origin was 

 probably due to volcanic subsidence, although there is a difference 

 of opinion regarding them. The first is 12.5 by 9 miles in greatest, 

 dimensions, the second, 9.5 by 3.5, and the third, 12.5 by 5 miles. 



Masaya-Nindiri volcano, in Nicaragua, is surrounded by the 

 remains of a crater that must have had a long diameter of 5 or 6 

 miles.S' ^ 



Crater Lake, in Oregon, occupies a deep caldera measuring 6 or 

 more by 4.5 miles and having an area of 20.5 square miles. '^ 



1 R. D. M. Verbeek, Topographische en Geologische Beschrijing Sumatra^ s 

 Westkust, Batavia, Landsdrukkerij, 1883. 



2 J. D. Dana, Characteristics oj Volcanoes, New York, Dodd, Mead St Co., 1890. 

 Also, Clarence Button, Hawaiian Volcanoes, Extract from 4tli Ann^ Rept., U. S. Geol. 

 Survey, 1882-83, pp. 126-28. 



3 C. H. Hitchcock, Bull. Geol. Sac. Am., Vol. CXII, October, 1906, pp. 485-96. 



4 This information was kindly furnished by Mr. W, H. Ochsner, of Stanford 

 University and the California Academy of Sciences, who recently returned frorn a 

 geological trip to these islands. 



5 E. G. Squier, The States 0} Central America, etc., New York, Harper & Bros., 

 1858. Also, A. Dollfuss and E. de Montserrat, Voyage geologique dans les repub- 

 liques de Guatemala et de Salvador, Paris, Imprimerie Imperiale, 1868. 



6 Karl von Seebach, Ueher Vulkane Centralamerikas; aus den 38sten Bande der 

 Abhandlungen der Koniglichen Gesellschaft der Wissenschajten zu Gottingen, Dieterich- 

 sche Verlags-Buchhandlung, 1892. 



7 J. S. Diller, Professional Paper, No. 3, U. S. Geol. Survey, 1902. 



