LINOS A AND ITS ROCKS 



17 



I 



la 



II a 



SiOa 



A1.03 



Fe,03 



FeO 



MgO 



CaO 



Na^O 



K,0 



H2O+.... 

 H,0-.... 



CO3 



TiO. 



ZrO. 



P2O5 



SO3 



CI 



Cr^Oj 



MnO 



NiO 



CuO 



BaO 



SrO 



o = ci 



48.06 



15-90 



3-37 



7-97 



7. II 



9-37 

 3-19 

 0.85 

 0.40 

 0.06 

 none 

 3-31 



0.36 



0.14 

 none 

 0.06 

 0.09 

 none 



48.84 

 14.62 

 2.08 

 9.00 

 7-15 

 9-33 

 2.86 

 0.89 

 o 49- 

 0.07 

 none 



3-57 

 none 

 0.36 

 0.05 

 0,42 

 none 

 0.04 

 0.08 

 none 

 none 

 0.04 



0.801 

 0.156 

 0.021 



O. Ill 



0.178 

 0.168 

 0.050 

 0.009 



0.814 



0.143 

 0.013 

 0.125 

 0.179 

 0.166 

 0.039 



O.OIO 



0.041 

 o . 003 

 0.002 



O.OOT 

 O.OOI 



0.045 



0.003 

 0.006 



O.OOI 

 O.OOI 



100.24 



■03 



99.89 

 .09 



99.80 



I. Auvergnose-camptonose (feldspar-basalt). Upper north flow of Monte Ponente, 

 Linosa. 



II. Auvergnose (feldspar-basalt). Lower north flow of Monte Ponente, Linosa. 

 la. Molecular ratios of I. 



Ila. Molecular ratios of II. 



The two analyses are very closely alike, there being no noteworthy 

 difference between the uppermost and the lowermost flow. The 

 small amounts of chlorine shown in these were extracted by water, 

 and belong (with equivalent amounts of sodium) to salt derived from 

 the sea-water, the waves of which break over the lavas. In the 

 columns of molecular ratios these amounts of NajO (0.002 in I and 

 0.006 in II) have been deducted. The small amount of SO3 in II 

 indicates the practically complete absence of gypsum in the specimen 

 analyzed. Among details to which attention may be called are the 

 great preponderance of ferrous over ferric oxide, and the high figures 

 for titanium dioxide and nickel oxide, features which will be dis- 

 cussed at length on a later page. The absence of copper, zirconium., 

 chromium, and barium, and the presence of but traces of strontium, 

 may also be noted. 



