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 27 (Monday, April 1, 2002): Erosion and Streams

Brief outline of this lecture:
Differential erosion
Landscapes undergoing erosion

Main points of this lecture:
Erosion is the removal of soil and pre-existing sediments by flowing water, air, or ice.
Steep slopes with little vegetation favor erosion.
Different rock types erode at different rates.
Erosion produces drainage patterns that vary with underlying geology and pre-existing overall slope.
Erosion commonly progresses from landscapes with broad uplands and few valleys to landscapes with broad valleys and isolated uplands.
Changes in base level cause changes in the extent of erosion or deposition on a landscape.

Figures used in this lecture:
Differential erosion
Some erosional landforms
Drainage patterns
Base level, and effects of falling base level
Effects of rising base level
Progress of erosion (landscape evolution)

Reading assignment: Chapter 6.

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