THE METAMORPHIC ROCKS OF ADELIE LAND . 8TILLWELL. 



47 



clear felspar is albitic and other plagioclase is much saussuritised, where biotite is replaced 

 by chlorite, where epidote partly replaces the calcic plagioclase thereby absorbing a 

 good deal of the lime content, where calcite also absorbs some of the lime content as in 

 No. 412, and where lawsonite is present, we have features of the epi division. Where, 

 however, we find considerable quantity of recrystallised clear andesine, biotite without 

 chlorite, and abundant clear hornblende with only rare transition to epidote, to chlorite, 

 or to glaucophane, we have dominant meso division features. Yet it is to be noted 

 that abundant saussurite and lawsonite is found with clear hornblende, saussurite with 

 clear felspar which is not albite, chlorite and epidote with biotite in the same section. 

 It, therefore, appears that the series has to be considered as more representative of the 

 transition types between the meso and epi divisions. 



^ 



o 

 c; 



<fl 



a 



mete-ten otil-h a 



: < 



amp hi Mi Ae 



^. 

 ^ 



Fig. 5. 



DIAGRAMMATIC SKETCH or THE AMPHIBOLITE DYKE No. 629 WITH 



THE SCATTERED META-XENOLITHS AND THE CLOTS OF CHLORITE 



ROCK AND EPIDOSITE. 



No. 153 is an epidote biotite schist and has suffered higher recrystallisation than the 

 epidote chlorite schist in family A of the epi division. With the temperature and the 

 uniform pressure approaching that of the middle zone, the chlorite has passed over to 

 biotite. The actual transition is found in No. 630, where the chlorite passes first into 

 green biotite and the latter into brown biotite. That the epidote remains after the 

 chlorite has changed to biotite is due to the fact that epidote can retain its water at a 

 much higher temperature than chlorite. Grubenmann points out that such individual 



