SLRATIGRAPHY AND SERUCTURE, OFTHE sPARKG 
CITY MINING DISTRICT, UTAH! 
J. M. BOUTWELL 
CONTENTS 
INTRODUCTION. 
GENERAL GEOGRAPHY. 
GENERAL GEOLOGY. 
STRATIGRAPHY. 
General Description. 
Weber Quartzite. 
Park City Formation. 
Woodside shale. 
Thaynes Formation. 
Ankareh Formation. 
Triassic. 
Jurassic. 
GENERAL STRUCTURE. 
INTRODUCTION 
The Central Wasatch supplied evidence for important principles 
to the pioneer geologists, and valuable data to succeeding investigators, 
and now, in the light of recent detailed studies, is proving to be a most 
fruitful geologic field. It was thus the source for epoch-making 
writings on orogeny by King and Emmons; for significant observa- 
tions on the relations of certain igneous masses to sediments by 
Geikie; for the determination of striking facts of pleistocene geologic 
history by Gilbert; and for important contributions by other geologists. 
The first detailed geologic mapping ia this historic region was 
undertaken in August, Ig02, in connection with an investigation of 
the geology and ore deposits of the Park City Mining District. This 
was continued through the field season of 1903 and completed in 1904. 
As a necessary preliminary, broad comparative studies of the geology 
of the range north and south of the immediate area under survey were 
made, and standard sections, notably one which was unusually well 
t Published by permission of the Director of the U. S. Geological Survey. 
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