SEQUENCE OF THE ERUPTIVE ROOKS 



The observations were made at room temperatures : 



363 



Geological age. 



Late Paleozoic (Car- 

 boniferous?) 



Jurassic. 



Close of the Laramie, 

 or Tertiary. 



Tertiary. 



Stage 



of 

 intru- 

 sion. 



(la. 



2. 



16. 



(3c. 



3a 

 and 

 36. 

 L 



f 

 i 



■!4. 



I 



(ha 

 and 

 56. 



6a. 



Name of body. 



Chopaka basic intru- 

 sives. 



Ashnola gabbro 



Basic complex (meta- 

 morphosed). 



Osoyoos Granodiorite 

 batholith (metamor- 

 phosed). 



Remmel Granodiorite 

 batholith ; two prin- 

 cipal phases due to 

 metamorphism. 



r 



Kruger Alkaline body. \ 



I 



Similkameen Granite 

 batholith; two prin- 

 cipal phases. 



Cathedral Granite batho- 

 lith, Older phase. 



Park Granite stock. 



Cathedral batholith, 

 Younger phase, 



Observed varia- 

 tion in 

 specific gravity. 



Gabbro, 2.959. 

 Dunite, 3.173. 



2.935-2.957. . . . 

 2.766-ca. 3.100. 



2.692-2.939. 



2.655-2.680... 



Malignites, aver- 

 age 2.824. 



Syenites, aver- 

 age 2.675. 



2.660-2.819. 



2.621-2.644. 



Average 

 specific 

 gravity. 



} 3.074 



2.946 



2.872 



2.746 

 2.720 



2.75Q 

 2.706 



2.631 



2.673 



2.608 



Magmatic stages la to 3b, inclusive, afforded non-alkaline rocks rich in 

 hornblende and carrying plagioclase, either basic or of medium acidity, as 

 the dominant feldspar. These bodies may be regarded as belonging to 

 one consanguineous series. Magmatic stages 4 to 7, inclusive, afforded 

 alkaline rocks bearing nepheline in the most basic phases and micro- 

 perthite (orthoclase in 66 and 7) as the dominant feldspar throughout the 

 series except in certain basiffed contact zones. This group belongs to a 

 second consanguineous series. Each series shows a steady increase of 

 .acidity and decrease of density as its different members were successively 

 intruded. With the exception of one abnormal stage, the same double 

 law underlies the entire magmatic succession. This exception is found 

 in the Kruger Alkaline body, which in almost every other respect as well 



