THE COMPOSITION OF KULAITE 



Several years ago I published 1 as an inaugural dissertation 

 an account of the volcanoes of Kula, in Lydia, Asia Minor. In 

 this the recent lavas of the region were described, to which 

 rocks the name of "Kulaite"was given, the definition being, 

 "a subgroup of the basalts which is characterized by the pres- 

 ence of hornblende as an essential constituent, which surpasses 

 the augite in quantity and importance." The varieties of 

 leucite-kulaite and nepheline-kulaite were also recognized, the 

 essential character of all being the predominance of hornblende 

 over augite. 



Although the analysis made for me by Dr. Rohrig showed, 

 for basalts, abnormally high Na 2 0, yet little attention was paid 

 to this feature and, attempts at identifying nepheline in the 

 groundmass having failed, the kulaites were regarded essentially 

 as plagioclase-basalts in which the pyroxene was largely replaced 

 by hornblende. 



In his latest book, Rosenbusch 2 recognizes this combination 

 of high alkalis with a basic combination, and refers them to his 

 group of trachydolerites, an intermediate group corresponding 

 to the latities of Ransome, 3 which are effusive equivalents of the 

 monzonites and intermediate between trachytes and andesites or 

 basalts. 



Study of other rocks of Asia Minor, which also showed 

 similar latitic features, as well as the growing importance of 

 these intermediate types, also called my attention again to the 

 Kula rocks, and led to a reexamination of them. This seemed 



1 The Volcanoes of the Kula Basin, in Lydia, New York, 1894. 



On the Basalts of Kula, Amer. Jour. Sci., Vol. XLVII, p. 114, 1894. 



2 Rosenbusch: Elemente der Gesteinslehre, p. 342, 1898. 



It is uncertain whether Rosenbusch understood these rocks to be without any 

 feldspar at all, or only without feldspar phenocrysts. 



3 Ransome: Amer. Jour. Sci., Vol. V, p. 373, 1898. 



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