IV TABLE OF CONTENTS. 



Pag«. 

 Beport of F. M. Endlich.— Continued. 



Keport on the geology of the White River District. — Continued. 



Chapter III. Correlations of stratigraphy, lithological constitution of 

 strata and orograi)hy. — Continued. 



Prozoic 103 



Metamorphics lOii 



Silurian 105 



Devonian 106 



Carboniferous - lOG 



Trias 107 



Jura lOS 



Cretaceous 106 



Post- Cretacous 10L> 



Tertiary '. 110 



Volcanic formations Ill 



Metamorphosed rocks 114 



Monuments 114 



Glaceatiou Il5 



Drift IIG 



Soil IIG 



Metalliferous deposits 117 



Gold and silver 117 



Copper, zinc, and lead 121 



Coal and iron 12:i 



MiNEKALOGiCAL Repokt OF F. M. Endlich, S. N. D. : 



Letter of transmittal 133 



Catalogue of minerals found iu Colorado 135 



Systematic arrangement of Colorado minerals 155 



Reference to publications on minerals of Colorado 158 



Eeport of a. C. Peale, M. D., Geologist of the Gj;and River District, 

 187G: 



Letter of transmittal ^ 161 



Geological report on the Grand River District : 



Chapter I. General introduction H\^i^■ 



Chapter II. Area A — San Mignel and Dolores Rivers — Saucer Valley- 

 Gypsum Valley — Basin Plateau — Paradox Valley— San Miguel Pla- 

 teau 1(j5' 



Chapter III. Area B — Grand River Valley— Roan or Book Cliffs— Little 



Book Cliffs 170 



Chapter IV. Geological formations of the Grand River District 178 



Upper Carboniferous 178 



Jura Trias 178 



Cretaceous 180 



Post-Cretaceous 181 



Tertiary 182 



Eeport of William H. Holmes: 



Letter of transmittal 487 



Eeport on the geology of the Sierra Abajo and West Sau Miguel Mountains. 189 



Dolores Canon 193 



San Miguel Mountains 193 



Bear River Mountains .^ , 195 



Report of F. M. Endlich, S. N. D. : 



Letter of transmittal 1 197 



On the erupted rocks of Colorado 199 



Chapter I. Introduction 199 



Classification 202 



Occurrence of volcanic rocks on the North American continent 204 



Occurrence of erupted rocks in Colorado 205 



Classification of erupted rocks in Colorado 207 



Chapter II. Plutonic eruptives 208 



Basic Plutonic eruptives 208 



Acidic Plutonic eruptives 210 



Chapter III. Volcanic eruptives 213 



Acidic volcanic eruptives 213 



Trachorheites , 213 



Andesite , 213 



Trachyte 214 



