Mount Hood in northern Oregon is an active stratovolcano just east of Portland, formed because of the subduction of the Juan de Fuca Plate under the North American Plate. Photo by Vince Cronin.
Igneous Rocks Lab — Chapter 5 from the AGI/NAGT Lab Manual
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- The reading assignments are in the required laboratory manual (textbook) listed near the bottom of this document.
- You must submit  the original paper lab-activity sheets on which you have recorded your answers (stapled together in order), and  a PDF file containing scans of the completed laboratory activities to your laboratory instructor before the end of your lab meeting.
- The end-of-lab quiz must be completed via the Canvas LMS within 6 hours after your laboratory meeting ends.
- View the pre-lab video Igneous Rocks and Processes at
- View the the pronunciation guide to AGI/NAGT Lab Manual chapter 5 at
- Scan: AGI/NAGT Lab Manual, chapter 5, Section Introduction, Pages 117-120.
- Read: AGI/NAGT Lab Manual, chapter 5, Section Classifying Igneous Rocks from the beginning through Subsection Textures of Igneous Rocks, Pages 120-123.
- Do: AGI/NAGT Lab Manual, Activity 5.1 Igneous Textures, page 135.
- Read: AGI/NAGT Lab Manual, chapter 5, Section Classifying Igneous Rocks, Subsection Mineral Composition of Common Igneous Rocks, Pages 123-126.
- Do: AGI/NAGT Lab Manual, Activity 5.4 Minerals That Form Igneous Rock, page 138.
All of the eight minerals in Activity 5.4 have tiny videos that are relevant to them, and that might be helpful to you. They are as follows:
specimen 1: unknown_5583_vc
specimen 2: unknown_4636_vc
specimen 3: unknown_3049_vc
specimen 4: unknown_4370_vc
specimen 5: unknown_4428_vc
specimen 6: unknown_6945_vc
specimen 7: unknown_7364_vc
specimen 8: unknown_3275_vc
- Read: AGI/NAGT Lab Manual, chapter 5, Section Classifying Igneous Rocks, Subsections Color Index for Mafic Minerals and Estimating Mineral Percentage in Rock, only the parts on page 126.
- Do: AGI/NAGT Lab Manual, Activity 5.5 Estimate the Percentage of Mafic Minerals, page 139.
- Read: AGI/NAGT Lab Manual, chapter 5, Section Classifying Igneous Rocks, Subsections Common Igneous Rock Types and Field Identification of Some Common Igneous Rocks, pages 127-132, including all figures and tables.
- Do: AGI/NAGT Lab Manual, Activity 5.7 Analysis and Interpretation of Igneous Rock, page 142-143, using the videos linked below.
Note that there might be two specimens of the same igneous type in the following list of specimens to be identified.
Identify these specimens, in the order given, on page 142 of the AGI/NAGT Lab Manual:
Identify these specimens, in the order given, on page 143 of the AGI/NAGT Lab Manual:
- Do: AGI/NAGT Lab Manual, Activity 5.8 Tectonic Setting of Some Major Volcanic Rock Types, page 144.
Summary of Assigned Lab Activities for This Week: Activities 5.1, 5.4, 5.5, 5.7, and 5.8
Required Textbook And Online Resources
AGI/NAGT Laboratory Manual in Physical Geology, 12th edition (paper copy)
Print Lab Manual ISBN: 9780135836972
Contacting Your Teachers
How To Contact Professor Cronin
Professor Cronin is available to facilitate understanding of course material that you have been studying and to help you navigate around any temporary barriers to your learning.
mobile, for text or voice: listed on the "lecture"-course homepage on Canvas.
Only contact him on his mobile device between 8 AM and 8 PM Central Time, and only if it is an important question/issue related to this course.
How To Contact Your Graduate Teaching Assistant
- Lab Section B (Tues 2:40-4:35 PM): Sanjukta Dhar — email Sanjukta_Dhar1@baylor.edu
- Lab Section C (Tues 4:40-6:35 PM): Sanjukta Dhar — email Sanjukta_Dhar1@baylor.edu
- Lab Section D (Wed 12:20-2:15 PM): Toluwaleke Ajayi (AJ) — email firstname.lastname@example.org
- Lab Section E (Wed 2:30-4:25 PM): Toluwaleke Ajayi (AJ) — email email@example.com
- Lab Section J (Thurs 2:40-4:35 PM): Vinothan Sivapalan — email firstname.lastname@example.org
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