CONTENTS. 
Page. 
Preface, by Alfred 11. Brooks 7 
Introduction '.» 
Geography 1 1 
(Miniate and vegetation 13 
Descriptive geology — 15 
General statement 15 
Stratigraphy 17 
Metamorphics (Paleozoic or pre-Paleozoic) __ 17 
Paleozoic 18 
Silurian and Devonian IS 
Carboniferous 22 
Mesozoic 23 
Cenozoic 24 
Tertiary 24 
Quaternary 25 
Igneous rocks • . 25 
Granitic 20 
Monzonitic 27 
Greenstones _♦ 27 
Basalt 2S 
Metamorphosed rhyolites 28 
Summary « . 2s 
Economic geology 29 
Fairbanks region 29 
< Jeneral statement 29 
Bed rock 31 
Alluvial deposits - 3 1 
Formation of placers .'51 
Source of the gold .".7 
Placers 37 
Fairbanks ("reek 38 
Goldstream basin 38 
Cleary Creek ____, 41 
Eldorado Creek 12 
Dome ( 'reek 43 
Vault Creek 13 
Our Creek 44 
Esther and ( 'ripple creeks II 
Smallwood ('reek ± 16 
Mining methods 47 
Prospecting I s 
Open-cut mining I s 
Drifting 18 
Costs .",(• 
Summary __ 5 I 
3 
