theImage.com     Notes on Basic Geology
Notes created & information organization based on the book:
"
The Dynamic Earth - an introduction to physical geology"
Brian Skinner & Stephen C. Porter   (further book information here)
also look at www.wiley.com for additional resource information
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Introduction - A First Look - Page 4

Heating Processes
Conduction Conduction is the movement of energy without the movement of mass. Heat one end of a metal rod and the heat will transfer to the other end.
Convection

Convection is the movement of heat by moving mass at the same time. Often it is caused by a change in density of the mass. Hotter materials tend to have less density than cooler materials.

The hot materials rise while cooler materials begin to descend.

Within the LITHOSPHERE the pressure and temperature produce rocks which are strong and rigid. Heat moves in this area via conduction.

Within the AESTHENOSPHERE pressure and temperature produces weak rock structures that provide a base for convection. Hot mass can rise while cooler masses can sink. Inside the lower areas of the earth heat moves by convection.

This is the process that will be studied in greater detail when we look at PLATE TECTONICS. It supplies the driving force for "continental drift", "sea floor spreading" and the creation of "new rock".

Conversion Calculator for Pressure and Stress
http://www.ex.ac.uk/cimt/dictunit/ccpress.htm
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