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Explore the importance of mineral sciences in geoscience curricula like volcanic petrology, crystallography, and geochemistry. Discover how to effectively teach students about rocks, minerals, and their significance in Earth science through interactive learning methods. Visit gtwist.ca for more information.
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Teaching Volcanic Petrology in Limited Time Jim Nicholls: Calgary, Alberta, Canadahttp://www.gtwist.ca The Mineralogical Sciences:Endangered topics in geoscience curricula
How has specialization been accommodated? Why Did This Happen? • One Contributing Factor • Students specialize as undergraduates: • Petroleum geologists, • Environmental geoscientists, • Geophysicists, • Etc. Created courses labeled Rocks and Minerals or Earth Materials or something similar. Learning Objective like: Students will develop the ability to Identify Rocks and Minerals
BUT • Mineral Science is more than identifying rocks and minerals! • Crystallography • Mineralogy • Geochemistry • Petrology • Optics and Diffractometry • The list goes on and on …
Ask a Couple of Critical Questions Why should any geoscientist know something about the mineral sciences? Geoscience is a profession with a focus on the Earth. Mineral sciences are part of that focus; any geoscientist should know something about them. What should they know about the mineral sciences? Depends on topic, but put everything on the table.Justify all content. Example: Volcanic Petrology.
Geoscientists Should be Able Read, Understand, and Review the Popular Literature
What’s written about igneous rocks in the popular literature? • Geoscientific context: Extensive, done well. • Stories are nearly always about volcanoes and volcanic phenomena. • Rock names: few, simple, unused or undefined. • Textures: names seldom used or described.
What to Leave Out? • Plutonic rocks • Rock names • Texture names Leaving this one out really sucks! (Well, almost)
What to Include (1) • Geoscientific context No more Rocks in Boxes • Descriptions of textures • Fragmental rocks (Explosive eruptions) • Flow rocks (Quiet eruptions) • Glassy rocks • Mafic – felsic continuum • Silica content versus Mafic index
What to Include (2) • Activity of silica • Activity of alumina Mineral assemblages reflect activities. Activities can be related to chemistry.
Using Activity: Challenges • Learning the concept • Applying concept • Conceptual model: Activity of sugar in water • Sugar – water solutions provide a physical, conceptual model (Kitchen stove, refrigerator, freezer). • Taste, stir, poke • Learning to relate specific mineral assemblages to chemical activities on a relative scale
Minerals and aSiO2 Students recognize whether a few different minerals are either present or absent from a rock. They can then infer relative activity of SiO2 or Al2O3.
Rock Space Rock Space encompasses 90% or more of volcanic rocks on Earth. Emphasizes the diversity of volcanic rocks on Earth. Simple to use and easy to learn.
Rock Names Provide Comfort and Support • The IUGS Classification has 179 root names(Le Maitre, 2002) • Muscovite Granite – a modified name • Granite – a root name • Basalt, Andesite, Rhyolite, Obsidian
Rock Names with Comfort and Support Rhyolite Andesite Basalt • Where, in Rock Space, Does Comfort and Support Fall? • Rhyolite • Andesite • Basalt • Obsidian
Explosive Eruptions, Craters, Calderas, and Activity of SiO2
Organizational concepts come before facts. Facts are learned by applying organizational concepts to case studies.
Acknowledgements • Dr. Paul Hoskin • Dr. Leslie Reid • Mavis Stout • Dr. Frank Brown • Dr. Thure Cerling • Erin Ernst • Colin Rowell • Michelle Speta • Elissa Lynn A detailed expression of the concepts described here can be down loaded from: http://www.gtwist.ca