Vi CONTENTS. 



i 'age. 



Chapter II. — Mesozoic geology, by George H. Eluridge 51 



Section I. — The formations 51 



Trias 51 



Wyoming formation 51 



Stratigraphy 51 



Correlat inn 56 



Jura 60 



Morrison formation '- 60 



Cretaceous 62 



Dakota formation 62 



Stratigraphy 62 



Life 64 



Colorado group- - - 64 



Benton formation: lower member of Colorado group 65 



Si rut igraphy - 65 



Life 66 



Niobrara formation : upper member of Colorado group 66 



strut igraphy 66 



Life 68 



Montana group - 68 



Pierre formation : lower member of Montana group 69 



Stratigraphy 69 



Life 70 



Zone transitional to Fox Hills 71 



Fox Hills formation : upper member of Montana group 71 



SI rut igraphy 71 



Life 72 



Laramie formation 72 



Stratigraphy, lower division 73 



Stratigraphj . upper division 75 



Stratigraphical relations - 76 



Life 77 



Section II. — Structure 79 



Introduction 79 



The foothills 80 



General structure 80 



Region about Golden 82 



Genera] features of the area affected 83 



The formations and their relations 84 



Structural features 89 



I levelopmeht of the area 91 



Discussion of movements producing the present structure 97 



Views of others on the struct tire of this region 101 



Special irregularities in the Golden region 103 



Eegion about Boulder 105 



Topographical features 105 



