This page provides a brief outline of, lists the main points of, gives links to figures for, and lists the assigned reading for a lecture in Dr. Bruce Railsback's GEOL 1121 class at the University of Georgia. This page is not intended as a set of lecture notes, and it cannot subsititute for a set of lecture notes. Familiarity with this page alone will not assure satisfactory grades on exams in the course.

Lecture 11 (February 11): Rock Deformation

Brief outline of this lecture:
Undeformed vs. deformed layered rocks
Kinds of stress
Kinds of rock deformation

Main points of this lecture:
We can use some basic rules to envision what layered rocks looked like before they were deformed.
There are three fundamental kinds of stress to which rocks are subjected (tension, compression, and shear).
The three kinds of stress can be linked to the three kinds of plate boundaries.
Stress causes deformation of rocks.
Rock deformation can be categorized as brittle or ductile.
Brittle and ductile deformation are favored by certain subsurface conditions and certain kinds of rocks.

Figures used in this lecture:
Steno's Principles - starting points for considering structures in rocks
Three kinds of physical stress that deform rocks
Kinds of rock deformation
Stress and deformation: a six-fold matrix
Montgomery Figure 3.3 (page 47)

Reading assignment: None.

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