THE ORIGIN OF RED BEDS 



A STUDY OF THE CONDITIONS OF ORIGIN OF THE PERMO- 



CARBONIFEROUS AND TRIASSIC RED BEDS OF 



THE WESTERN UNITED STATES 1 



C. W. TOMLINSON 



University of Minnesota 



PART I 

 Preface 



Summary Description of the Features Considered 

 List of Formations 

 Colors of Gypsum and Limestone 

 Color in Clastic Strata 

 Distribution of Greenish Colors 

 Nature of the Coloring Matter 



Is the Ferruginous Material an Original Constituent of the Sedi- 

 ments, or a Later Introduction ? 



Hypothesis of Introduction of Iron from Igneous Magmas 

 Later Introduction of Iron by Meteoric Waters 



Deposition of Coloring Matter Contemporaneous with Sedimentation 

 Microscopic Evidence 

 Extent of Known Secondary Redistribution of Coloring Matter 



Is the Ferruginous Material in the Same Form as at the Time of 

 Sedimentation ? 

 Variations in Degree of Oxidation 

 Origin of Mottling 



Cause of Gray and Green Bands in Red Beds: BarrelPs Hypothesis 

 Organic Matter the Controlling Influence in the Case of the Western Red 



Beds 

 Variations in Hydration of Ferric Oxide 



Was the Coloring Matter a Chemical or a Mechanical Sediment ? 



1 A revision of a thesis presented in partial fulfilment of the requirements for the 

 degree of Master of Arts at the University of Wisconsin, in June, 1914. 



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