TABLE OF CONTENTS xxv 



PAGE 



III. Dolomitizatinn of Limestones 759 



IV. Replacement of Limestone by Siliea, Iron Oxide, etc. (762); 

 V. Desalinification (763); VI. Formation of Concretions (763); 



VII. Hydration and Dehydration 762-765 



Contact Metamorphism or Aethoballism 765 



I. Pyrometamorphism (765); 2. Hydrometamorphism (766); 



3. Atmometamorphism (767); 4. Biometamorphism ...765-768 



Dynamic or Pressure Metamorphism, or Symphrattism 768 



The Terms Slate, Schist and Gneiss (770); General Terms 

 for Metamorphic Rocks (771); Variation in Metamorphism 



of Strata (772) ; Age of Metamorphic Rocks 770-773 



Bibliography XIX 773 



CHAPTER XX. 



Deformation of Rock Masses 776 



Endogenetic Deformations 777 



I. Endolithic Brecciation (777); 2. Enterolithic Structure 

 (778) ; 3- Contraction Joints, Basaltic Jointing 777-778 



Deformation Due to Extraneous Causes — Exogenetic Deformations. . 779 



A. Gravitational Deformation 779 



a. Structures due to Movements 779 



4. Intraformational Brecciation. 779 



5. Subaquatic Gliding Deformation 780 



Examples of Fossil Subaqueous Solifluction (781) A. 

 Miocenic Sublacustrine Glidings of Oeningen (781); 



B. Jurassic Deformations (781); C. Triassic Examples 

 (782); D. Devonic Examples (782); E. Ordovicic Ex- 

 amples (783); F. A Cambric or Earlier Example 781-784 



6. Surface deformations Due to Creep 785 



b. Deformations due to Vertical Pressure of Overlying Rock 

 Masses (785); 7. Squeezing Out of Layers; 8. vShaliness; 9. 

 Slatiness 785-786 



c. Of Complex Origin (786); 10. Pressure Sutures and Sty- 

 lolites (786) ; 1 1 . Cone in Cone 786-788 



B. Tectonic or Orogenic Deformations 789 



d. Deformations Resulting in Fractures and Related Struc- 

 tures 789 



12. Joints (789); Minor Characters of Joints; Feather 

 Fractures; Dendritic Markings; Widening of Joints. . . .789-791 



13. Earthquake Fissures (792); 14. Slaty' Cleavage (793); 

 15. Fissility (794); 16. Schistosity (794); 17. Gneissoid 

 Structure 792-795 



e. Deformation due to Folding and to Folding and Erosion.. . 795 



18. Folding (795); a. Anticlines (795); b. Synclines (795); 

 c. Isoclines (796); d. Fan Folds (798); e. Monoclines (798); 

 Anticlinoria and Synclinoria (799); Geosjmcline and Fore- 

 deep 795-799 



Relation of Dip Strike and Outcrop (800); Strike as 

 Affected by Pitching Axis of Folds (806); Folding as 

 Indications of Unconformity (815); The trend of the 

 Appalachian Folds 800-807 



