E-Learning - The Earth and Beyond

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Traditional Aboriginal Knowledge

E-Learning - The Earth and Beyond


back to Contents of the Entire Course...
 
Geology, What is it?    
Why Study the Earth?    
Earth Materials and Processes
Principle of Uniformitarianism    
Energy Heat Transfer    
Geothermal Gradient
The Earth -- What is it?    
Internal Structure of the Earth
Surface Features of the Earth    
Plate Tectonics


adapted to HTML from lecture notes of Prof. Stephen A. Nelson Tulane University

Geology, What is it?


Geology is the study of the Earth. It includes not only the surface process which have shaped the earth's surface, but the study of the ocean floors, and the interior of the Earth. It is not only the study of the Earth as we see it today, but the history of the Earth as it has evolved to its present condition.

Thus, organisms have only been witness to about 15% of Earth's history. Thus, for us to have an understanding of the earth upon which we live, we must look at processes and structures that occur today, and interpret what must have happened in the past. One of the major difficulties we have is with the time scale. Try to imagine 1 million years-- That's 50,000 times longer than most of you have lived. It seems like a long time doesn't it? Yet, to geologists, 1 million years is a relatively short period of time. More discussion about time in later lectures. But one thing we have to remember when studying the earth is that things that seem like they take a long time to us, may take only a short time to earth.
Examples:
Things can change drastically!

Why Study the Earth?




Earth Materials and Processes


The materials that make up the Earth are mainly rocks (including soil, sand, silt, dust) .  Rocks in turn are composed of minerals.  Minerals are composed of atoms, Processes range from those that occur rapidly to those that occur slowly