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Delicate Arch, Arches National Park, Utah

An Introduction to Geology

Written by

Chris Johnson, Matthew D. Affolter, Paul Inkenbrandt, Cam Mosher

Salt Lake Community College – 2017

Contact the authors at edits (at_) with edits, suggestions, or if adopting the book.

Faculty who adopt this text for their course should contact the authors at edits (at_)  so that the authors can keep faculty users up to date of critical changes.


Edited and Reviewed by

Johnathan Barnes – Salt Lake Community College
Jack Bloom – Rio Tinto Kennecott Copper (retired)
Deanna Brandau – Utah Museum of Natural History
Gereld Bryant – Dixie State University
Gregg Beukelman – Utah Geological Survey
Peter Davis – Pacific Lutheran University
Renee Faatz – Snow College
Gabriel Filippelli – Indiana University-Purdue University Indianapolis
Michelle Cooper Fleck – Utah State University
Colby Ford – Dixie State University
Michael Hylland – Utah Geological Survey
J. Lucy Jordan – Utah Geological Survey
Mike Kass – Salt Lake Community College
Ben Laabs – North Dakota State University
Tom Lachmar – Utah State University
Johnny MacLean – Southern Utah University
Erich Peterson – University of Utah
Tiffany Rivera – Westminster College
Leif Tapanila – Idaho State University

Special Thanks to

Jason Pickavance – Salt Lake Community College, Director of Educational Initiatives
R. Adam Dastrup – Salt Lake Community College, Geoscience Dept. Chair, Director of 

Open Educational Resources

This text is provided to you as an Open Educational Resource which you access online. It is designed to give you a comprehensive introduction to Geology at no or very nominal cost.  It contains both written and graphic text material, intra-text links to other internal material which may aid in understanding topics and concepts, intra-text links to the appendices and glossary for tables and definitions of words, and extra-text links to videos and web material that clarifies and augments topics and concepts.   Like any new or scientific subject, Geology has its own vocabulary for geological concepts.  For you to converse effectively with this text and colleagues in this earth science course, you will use the language of geology, so comprehending these terms is important.  Use the intra-text links to the Glossary and other related material freely to gain familiarity with this language.

Tips for study

Each chapter begins with a list of KEY CONCEPTS you should be able to grasp through effective study of the chapter material.  These are stated as Student Learning Objectives (SLOs) in behavioral terms.  In other words, when you have completed study of that chapter, you should be able to do stated things with your understanding.  Within chapters, each section concludes with a set of questions, called “Did I Get it?” questions. After completing the section, you should get these key points and answer questions related to the student learning objectives.  At the end of each chapter are summaries of the sections and chapter review questions so you can review each section in the context of the chapter.