Granitic Rocks and Geologic History of the Idaho Batholith part of Cutting Edge:Petrology:Teaching Examples
This is a lab/project in which the students not only name and identify a suite of granitic rocks but try to piece together the tectonic and geologic history of the Idaho batholith. This activity brings together the process of naming rocks, determining the I-, S- and A-type nature of the rocks, estimating magma source and potential assimilants, a nonquantitative depth of intrusion for the suites, and any distinctive textures that might help tell the story of the batholith. It forces students to move outside the rock in a box lab for granites and create a regional geologic history.
Major Element Fractionation During Differentiation part of Cutting Edge:Petrology:Teaching Examples
This problem set introduces some of the more advanced uses of Excel to not only calculate how the chemistry of a magma changes with crystallization but also to see how the liquidus assemblage can drastically change the evolution of the remaining magma. Once they have their calculations complete, students plot the results and answer questions on the geochemical trends observed through the crystallization sequence. This problem set reinforces quantitative problem solving skills using a spreadsheet and has the students think about mineralogical controls on magma evolution.
The nature of volcanism as controlled by viscosity part of Cutting Edge:Petrology:Teaching Examples
This activity is fun to include in a classroom. This activity has the students design demonstrations using ketchup and peanut butter to document how viscosity differences between rhyolite and basalt control various behaviors.