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Canada 
Geological Survey 
Museum Bulletin No. 30 
GEOLOGICAL SERIES No. 37. 
CONTENTS. 
Page. 
Introduction • 1 
General geology 2 
Lithological characters and mode of occurrence 3 
General description 3 
Detailed descriptions 6 
Olivine gabbro 6 
Augite gabbro 8 
Gneissic phases 8 
Anorthosites 9 
Granite ; 10 
Dykes . , . . . 10 
Veins 12 
Hornblendite veins 12 
Gabbro-aplite veins 13 
Aplite veins . 14 
Relations to. the gabbro . 16 
Changes of composition during hornblendization and 
aplitization 16 
Rock alterations 18 
Triple points . . 20 
Internal structural relations . . , 21 
Spatial and contact relations 21 
Jointing and faulting 24 
Mineral deposits 26 
Theoretical part 29 
Introductory statement 29 
Proof of differentiation 30 
Composition of the original magma.,.. ■ 30 
Proof of movement prior to consolidation 31 
Time of movement . 31 
Time of differentiation relative to intrusion 32 
Method of differentiation 33 
Spatial relations 7 34 
Proportional relations of minerals . 34 
Changes in composition of constituent minerals 35 
Special textures and structures 36 
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