Geology 101 - Lecture 1

I. Goals of course

To give you an understanding of the physical world around you.
Topography of the Earth
Global topography of the seafloor
Digital relief map of Washington State

Do you know:

If we can expect major earthquakes in Washington?
Why Hawaiian volcanoes are less dangerous than Cascades?
Why is Mt. St. Helens where it is?
Why do we have ice ages?
When was the last ice age?
How old is the Earth?

Course details: see syllabus

II. What is Science?

A way of knowing.
Science endeavors to understand and explain how the natural world works and how it got to be the way it is.
Natural world - empirical or "sensible", not supernatural

Fact vs. hypothesis

What is a fact?

A confirmed or agreed upon observation or conclusion What is a hypothesis?

A proposed explanation of certain "facts" that must be testable in some conceivable fashion. Hypotheses are never proven true or correct. They are either rejected because they are determined to be inconsistent with the data, or, if not rejected, they are kept as working hypotheses to be used until found to be faulty in light of new evidence or testing. Hypotheses that have stood up to numerous, rigorous tests and not found to be "false" are often regarded as "facts" since they are effectively beyond dispute.

Theory

A theory is an integrated, comprehensive explanation of many "facts". The best example in geology is plate tectonic theory, which explains many observations and many tested hypotheses about how the earth works.

Scientific Law

A generalization about the behavior of nature from which there has been no known deviation after numerous observaations or experiments. Narrower in scope than theories, they can usually be expressed mathematically.
Example: Newton's law of motion, or the laws of thermodynamics
A law describes what happens in nature, but not why

How do we "do" science?

The way we "do" science is by constantly testing and refining hypotheses.

1. Collection of scientific facts through observation and measurement
2. Development of a working hypothesis to explain those facts
3. Construction of experiments to test the hypothesis
4. The acceptance, modification, or rejection of the hypothesis based on extensive testing.