Stockdale: Stylolites 



3 



PART III. A STUDY OF THE STYLOLFrES OF THE INDIANA LIME- 

 STONES AND THE CONCLUSIVE EVIDENCE OF THEIR 

 ORIGIN BY CHEMICAL SOLUTION 



Page 



Geologic Distribution of Stylolites in Indiana 35 



Harrodsburg Limestone 35 



Salem Limestone 35 



Mitchell Limestone 37 



General Description of Indiana Stylolites 38 



Relation to Stratification 43 



Physico-Chemical Basis of the Solution Theory 46 



Statement of the Theory 46 



Effect of Carbon Dioxide upon Solution 46 



Effect of Pressure upon the Solution of Gases in Liquids 46 



Effect of Temperature upon the Solution of Solids in Liquids 47 



Effect of Pressure upon the Solution of Solids in Liquids 47 



Result of Supersaturation of a Solution 47 



Solubility of Limestone 48 



Explanation of Stylolitic Phenomena under the Solution Theory. ... 49 



Conclusive Evidence which Establishes the Solution Theory of the 



Origin of Stylolites, and Opposes the Pressure Theory 55 



1. Evidence that Stylolites Originate in Hardened Rock with the 



Actual Removal of Rock Material 55 



Relation of Stylolites to the Lamination of the Rock 55 



Relation of Stylolites to the Color of the Rock 59 



Relation of Stylolites to Fossils 61 



Penetration of One Stylolite-Seam by Another Adjacent Parallel 



Seam 64 



Striated and Slickensided Faces of Stylolites 64 



Direction of Stylolites and Stylolite-Seams 66 



2. Evidence that the Clay Partings Are the Solution Residue of 



the Dissolved Limestone 67 



Chemical Relations between the Clay Caps and the Associated 



Limestone 67 



Relation between the Thickness of the Clay Caps and the Size 



and Composition of the Stylolites 83 



Occurrence of Corroded Fossil Fragments in the Clay Residue 85 



Subordinate Features of the Clay Caps 85 



3. Stratigraphic Evidence which Precludes the Pressure Theory and 



Supports the Solution Theory 86 



Occurrence of Stylolites Only in Soluble Rocks 86 



Occurrence of Angular Stylolite-Seams 86 



Occurrence of Branching Stylolite-Seams 86 



Occurrence of Stylolites along Disconformities 88 



4 , Other Evidence which Supports the Solution Theory 88 



Deposits of Mineral Matter 88 



Analogy of the Origin of Stylolites to that of Impressed Pebbles 89^ 



Conclusion 89 



Summary 90 



Bibliography 93 



2—22663 



