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 1 (January 7): Basic Concepts

Brief outline of this lecture:
1. Scales of observation
2. Scientific Understanding
3. Age of the earth
4. The Geologic Time Scale

Main points of this lecture:
Natural systems can be viewed profitably at a variety of scales of observation.
Facts (demonstrable observations, or truths known by actual experience or observation) are the building blocks of science - no less and no more.
Scientific theories provide a framework with which to understand natural phenomena and from which to make predictions, but they do not provide certainty or permanence.
We think the Earth is 4.6 billion years old.
We have at least four good reasons to think the earth is 4.6 billion years old.
4.6 billion years is a very long time.
The geologic time scale provides a useful if idiosyncratic way to compartmentalize time in Geology.

Figures used in this lecture:
Scales of Observation
Facts, theories, and hypotheses
An introduction to maps, cross-sections, and 3D diagrams.
Geologic exposures in the field - sources of geological information
Evidence regarding the age of the Earth
The standard geological time scale to be known for this course
The standard and two non-standard geological time scales

Reading assignment: Reading: pages 505 through 511.

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