Monday, April 9
Quiz on Geologic Time Scale and Formation symbols
Introduction to stress, strain: Units of stress, Shear and normal stress, Mohr Diagram for stress

The quiz will cover the geologic time scale. Know the Eons, Eras, Periods, and for the Cenozoic, the Epochs of the Quaternary. Also know how a formation name and age go together to make a map symbol (eg. Kd for Cretaceous Dakota Formation).

Reading: Davis and Reynolds, Chapter 3, "Dynamic Analysis", p. 98-117. The most important part of this reading for our purposes is the section on "stress calculations" (p. 110-114). Spend some time with these calculations to convince yourself that stress on a given plane resolves itself into a single stress tensor. From this tensor, you can figure out the specific shear and normal stress components on the plane.

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Wednesday, April 11 Finish Stress: Mohr diagrams

Reading: Davis and Reynolds, Chapter 3, "Dynamic Analysis", p. 117-122. The Mohr diagram is extremely important in understanding how shear stress relates to normal stress on differently oriented surfaces. Because stresses control the formation of virtually all known structures, we will use it frequently to understand their formation. It will be especially relevant to the formation and orientation of faults and fractures.

handout homework assignment on Mohr Circle. Due, Wednesday, April 18 in class.

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Friday, April 13 Introduction to Strain

Reading: Davis and Reynolds, Chapter 2, 'Kinematic Analysis", p. 51-67; 83-85. Davis and Reynolds present a fairly complete treatment of strain and its analysis; however, we don't have the time to cover it in nearly as much detail. In lecture, we will emphasize those aspects of strain which underlie much of structural geology, namely the concepts of elongation, stretch, and shear strain, and the strain ellipse. Finally, we will compare and contrast pure shear and simple shear.

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LAB Introduction to Geometrical Principles --part II

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