4 CONTENTS. 



Geology — Continned. 



Description of sedimentary formations — Continued. 

 Carboniferous r(icks — Continued. 



Mansfield sandstone 35 



Character 25 



Distribution 26 



Name and correlation 26 



Tertiary deposits 26 



Quaternary deposits 27 



Loess loam . _ . _ 27 



Alluvium 27 



Description of igneous rocks 27 



General statement . . . 27 



Orr"s landing 28 



Rosiclare quarry 28 



Downey's bluff 29 



So ward farm 30 



Mix farm 30 



Golconda 80 



Geologic structure 31 



General relations 31 



Hicks dome 31 



Faults 32 



Quartzite reefs 33 



Dip 33 



Geologic history 34 



Periods of sedimentation 34 



Deformation and intrusion of igneous rocks. 35 



Period of erosion ' 35 



The ( )re deposits 36 



General character 36 



Minerals present . . 36 



Gangue minerals 36 



Fluorite 36 



Calcite '. 37 



Quartz . _ . 37 



Barite - - . - - 37 



Dolomite 38 



Kaolin .-. 38 



Original metallic minerals - - — 38 



Galena . 38 



Blende 38 



Pyrite 39 



Chalcopyrite 39 



Stilmite 39 



Secondary minerals . ._.... ...... 39 



Cerussite . 39 



Smithsonite - 39 



Limonite . . . 39 



Malachite 39 



Copper 39 



Paragenesis and association 40 



