CONTENTS 
Page. 
Letter of transmittal, by Alfred H. Brooks . . 7 
Introduction 9 
Controller Bay region 11 
Geography 11 
Geology 12 
Semimetamorphosed rocks 12 
Katalla formation 13 
Kushtaka formation . _ 14 
Miocene rocks . . . 15 
Igneous rocks 15 
Pleistocene and Recent deposits 16 
Glaciers and glacial deposits 17 
Structure 17 
Details 17 
General features 20 
Economic materials ... . _ 22 
Petroleum 22 
Petroleum seepages 22 
Petroleum wells w 23 
Structural relations of the petroleum . 25 
Cape Yaktag petroleum field 26 
Geology 26 
Occurrence of the petroleum 27 
Coal 27 
Bering River coal field 27 
The field 27 
Geologic occurrence of the coal 27 
Character of the coal 31 
Methods of shipment _ . . 34 
Cook Inlet petroleum fields 37 
Geography 37 
Geology 37 
Pre- Jurassic crystallines and intrusives 38 
Middle Jurassic rocks 38 
Enochkin formation 38 
Upper Jurassic rocks 44 
Agglomerate 44 
Naknek formation * 44 
Post- Jurassic rocks 45 
Structure _ 46 
Occurrence of petroleum : 47 
Surface indications 47 
Development 48 
3 
