Subsurface Laboratory Methods 



271 



cant possibilities in mapping alteration zones associated with mineral 

 deposits in studies of the type reviewed by Kerr.^^ 



The thermal curves thus far obtained in these studies are for the most 

 part consistent with curves recorded in the literature, allowing for the 



100 



80 



60 - 



% KAOLINITE 

 IN MIXTURE 



40 



20 - 



100 



- 80 



40 



20 



PEAK AMPLITUDE (arbitrary units) 



Figure 119. Graph showing variation in position and amplitude of the 605° C. peak 

 of kaolinite in various artificial mixtures. 



variation in heating rates. The temperatures at which peaks occur have 

 been agreed upon by various observers with different types of apparatus, 

 if the heating rates, the thermocouples, and the size of sample are con- 

 stant. The amplitude of the peaks for any given concentration of active 

 ingredient is a function of the sensitivity of the individual apparatus. 



'Kerr, P. F., Alteration Studies: Am. Mineralogist, vol. 32, p. 158, 1947. 



