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 10 (Wednesday, February 6): Some closing observations about rocks

Brief outline of this lecture:
Origins of breccias
Relative abundances of fundamental rock types
Relative abundances of sedimentary rocks
Answers to student questions over the material covered for Exam I.      

Main points of this lecture:
Breccias (coarse-grained angular "sedimentary" rocks) have a variety of origins.
Igneous and metamorphic rocks make up much of the volume of the continental crust.
Sedimentary rocks cover much of the surface of the continental crust.
Shale is the most abundant sedimentary rock.

Figures used in this lecture:
Proportions of rock types in earth's crust
Origins of breccias
Properties and use of different kinds of rocks (probably won't be used)

Reading assignment: None.

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Railsback's main 1121 web page
Railsback's main web page
UGA Geology Department web page